trek bb90 30mm spindle

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Trek BB90 and 30mm spindle cranks

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Post by jdc5r » Mon Apr 18, 2016 10:47 am --> by jdc5r on Mon Apr 18, 2016 10:47 am

by » Mon Apr 18, 2016 10:47 am --> by Weenie on Mon Apr 18, 2016 10:47 am

Post by jdc5r » Mon Apr 18, 2016 10:59 am --> by jdc5r on Mon Apr 18, 2016 10:59 am

Post by Tenlegs » Mon Apr 18, 2016 11:31 am --> by Tenlegs on Mon Apr 18, 2016 11:31 am

Post by jdc5r » Mon Apr 18, 2016 11:46 am --> by jdc5r on Mon Apr 18, 2016 11:46 am

Post by Dagger9903 » Wed Dec 07, 2016 5:05 pm --> by Dagger9903 on Wed Dec 07, 2016 5:05 pm

Post by Lelandjt » Wed Dec 07, 2016 5:53 pm --> by Lelandjt on Wed Dec 07, 2016 5:53 pm

Post by Lelandjt » Wed Dec 07, 2016 5:54 pm --> by Lelandjt on Wed Dec 07, 2016 5:54 pm

Dagger9903 wrote: When THM says their crank works with a Shimano pressfit BB, does that include BB90? I can't figure out if the THM SE's are wide enough at the spindle to fit.

Post by deek » Wed Dec 07, 2016 6:04 pm --> by deek on Wed Dec 07, 2016 6:04 pm

Post by Dagger9903 » Wed Dec 07, 2016 6:44 pm --> by Dagger9903 on Wed Dec 07, 2016 6:44 pm

Lelandjt wrote: Dagger9903 wrote: When THM says their crank works with a Shimano pressfit BB, does that include BB90? I can't figure out if the THM SE's are wide enough at the spindle to fit.

Post by deek » Wed Dec 07, 2016 7:46 pm --> by deek on Wed Dec 07, 2016 7:46 pm

Post by grover » Wed Dec 07, 2016 9:50 pm --> by grover on Wed Dec 07, 2016 9:50 pm

Post by hambini » Wed Dec 07, 2016 10:06 pm --> by hambini on Wed Dec 07, 2016 10:06 pm

grover wrote: It's possible but I wouldn't do it. Your bearings won't last long. They're tiny. And with an sisl2 crankset you'll probably have to use a longer spindle throwing out your chainline and q-factor. Firstly the bearings you need are 6706. 30mm ID, 37mm OD, 4mm width. You use two on each side next to each other to make a bearing 30mm ID, 37mm OD, 8mm width. BB90/95 was originally designed around a bearing 7mm wide. So your new arrangement adds 1mm of width to each side. This makes a bearing cover practically useless so don't use one. (another reason your bearings won't last long). Now you install the crankset as normal. You'll have to play with spindle lengths and spacers.

Post by glam2deaf » Wed Dec 07, 2016 10:09 pm --> by glam2deaf on Wed Dec 07, 2016 10:09 pm

deek wrote: You're just going to have to use some bearings with very tiny balls that will likely not last very long at all which you seem to be aware of.

Post by ms6073 » Thu Dec 08, 2016 4:25 am --> by ms6073 on Thu Dec 08, 2016 4:25 am

grover wrote: And with an sisl2 crankset you'll probably have to use a longer spindle throwing out your chainline and q-factor.

Post by Dagger9903 » Thu Dec 08, 2016 6:26 am --> by Dagger9903 on Thu Dec 08, 2016 6:26 am

by » Thu Dec 08, 2016 6:26 am --> by Weenie on Thu Dec 08, 2016 6:26 am

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Confused by bottom brackets? Wondering what the ‘BB’ in BB90 stands for? Let alone the ‘90’… Well, don’t despair. I’ll be explaining what this essential bike component does, why the BB90 is unusual, and what you can do about common issues that can develop with them. Let’s take a look.

What does a bottom bracket do?

The bottom bracket is one of the most important components in a bicycle, yet it’s often overlooked. When you’re shopping for a new road bike you might be concerned with overall bike weight or gear ratios. For a new mountain bike, it might be the travel of the suspension or the gnarliness of the tires. And, for an electric bike, it could be the torque and range that the battery and motor deliver.

But, bottom brackets? They’ll be tucked right at the bottom of the spec list and are unlikely to be a factor in most purchases.

It’s easy to forget about the bottom bracket, but it plays an integral role in your riding experience and, when it goes wrong, it can really ruin your day . So, let’s break it down: what exactly is a bottom bracket, and what does it do?

A bottom bracket ( often referred to as a ‘BB’ ) is a small part of the bike that holds the crank arms in place and attaches them to the frame. It’s located at the bottom of the bike between the two chainrings, and it consists of two bearings (called cups) that are pressed into the frame through the bottom bracket shell. The bearings allow the crank arms to spin freely, which is crucial for smooth friction-free pedaling. A BB is part of a bike’s groupset .

The bottom bracket also determines the size of your crankset. Different sizes are available and they’re measured in millimeters (mm).

For most riders, the size of the bottom bracket isn’t something they need to worry about—they simply purchase a bike with the correct size already installed. However, if you’re planning on upgrading your crankset, you’ll need to consider the size of your bottom bracket.

Aside from these considerations, there are a few other aspects to keep in mind when selecting a bottom bracket. One is bearing type: sealed bearings are preferred because they are low-maintenance and provide smoother rotation than unsealed bearings. The other is spindle diameter—the part of the bottom bracket that your pedal crank arms attach to. The two spindle diameters most commonly used today are 24mm (used on Shimano cranksets) and 30mm (used on SRAM cranksets).

Bottom brackets are also available in different configurations and materials. For example, some are threaded into the frame, while others press-fit into it. The most common materials for bottom brackets include aluminum alloy, steel, and titanium. Each material has its own unique qualities and benefits, so it’s important to choose one that fits your riding style and budget.

What is the BB90 bottom bracket?

Intriguingly, the BB90 isn’t really a bottom bracket at all. Let me explain.

A ‘typical’ bottom bracket has a cylindrical body that takes up the entire inner space of the bottom bracket shell. It might have a spindle fitted allowing crank arms to be attached, or have a slot through the center allowing for a spindle to be pushed through – an example of this type is shown below.

In contrast, the BB90 ‘bottom bracket’ is really only the two bearing cups that you’d normally find at each end of a standard bottom bracket.

This is a press-fit style of bottom bracket, where the bearing cups push into recessed fittings on each end of the bottom bracket shell on a bike. You can see what the BB90 setup looks like in the diagram below.

Let’s look at the dimensions now.

Remember we talked about the ‘90’ in BB90? Well, this refers to the length of the BB shell cylinder, which should either be 90.5mm (on road bikes) or 95mm (on mountain bikes ).

Each of the two bearing cups in the BB90 has an outer diameter of 37mm – corresponding to the inner diameter of the BB shell. They also have an inner diameter of 24mm to accept the 24mm spindle cranks that they are designed to be used with.

Which bike manufacturers use BB90 bottom brackets?

There is really only one bike manufacturer that uses BB90 and that’s Trek Bikes . BB90 is their standard for most of their road bikes and mountain bikes. These will have a BB shell that is designed to accept this style of bottom bracket.

BB90 Bottom Bracket problems

BB90 is a clever bit of design as it allows for a reduction in bike weight (through doing away with the bottom bracket ‘body’ that normally goes between the bearing cups).

But, it’s not without its problems. The chief problem that many riders complain about is a creaking noise as the cranks rotate. Whilst not necessarily a loud noise, it’s enough to set the teeth on edge of both the rider and the rest of the pack.

The most common attempt at resolving this issue is with liberal application of Loctite . Sadly, this is unlikely to give anything more than temporary relief.

eliminate a creaking bb90 with this alternative bottom bracket

A better solution is to replace the two BB90 bearing cups with what looks like a standard bottom bracket. This design gives a solid threaded-together casing that holds the bearing cups snugly in position, allowing them to spin smoothly and quietly.

BB90 bottom bracket replacement

If you’re comfortable with tricky bike repairs , then either replace the bearings, or (my preference) use a BB90-compatible thread-together bottom bracket (which is more akin to a ‘standard’ bottom bracket in that it goes all the way through from one side of the BB shell to the other holding the bearing cups in each end, and the 24mm spindle slots through the middle) – see above.

Replacement of bottom brackets is really a job best left to the pros at your local bike shop. They have the specialist tools to do it, and they’re replacing them day-in and day-out. That said, if you’re handy with complex bike repairs and don’t mind getting your hands dirty, then take a look at the details in the video below:

What’s the future of BB90 bottom brackets?

Whilst these can be a weight saver, due to the elimination of the overall bottom bracket ‘body’, the creaking problems that many riders experience with BB90 setups mean that these aren’t universally adored. This may be one of the reasons why there are signs that Trek may be looking to shift gradually away from the BB90 to a different standard: PF92/BB92.

Watch this space to see what happens.

Bottom Bracket Tech Breakdown

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Ever get confused by all the bottom bracket “standards” out there? English thread vs. Italian thread. BB30, BB86 and BB90?

No worries. Here’s your primer on all things bottom bracket, from it’s history and humble beginnings all the way up to today’s emerging technology. It’s everything you need to know about bottom brackets…

The Basics:

The bottom bracket is a critical component to every drive train. Connecting the left and right cranks, this is one of those important elements on the bike that directly effects power transfer between the rider’s legs and the bike’s drivetrain.

While its concept is simple enough to understand, when it comes to bottom bracket technology, it’s easy to get confused. Incremental changes almost every year coupled with a slew of proprietary technologies from major component companies have flooded the market with more options than ever before, and it can be very confusing for the average cyclist. We broke down every type of bottom bracket you are likely to encounter and present them in a simple, easy to understand format. From mountain to road, threaded to pressed, and integrated to external, it’s all here…

Why The Variety?

Bottom bracket compatibility is one of the most confusing topics for amateur and seasoned cyclists alike. Years ago, it was simple. There was one bottom bracket design, and it was strong, durable, and easy to service. Commonly referred to as “one-piece” Ashtabula cranks, these are made of one solid metal piece, meaning the left crank, the axle, and the right crank are all one piece, held in place by cups pressed into the bottom bracket shell. If you still have an older bike or even a newer children’s or department store bike, chances are you will be able to find one of these on there.

Durable and simple as they may be, these cranks are heavy and inefficient. Component manufacturers found that they could shave significant weight and improve stiffness by manufacturing parts from lighter materials, but in order to maintain the integrity of the set ups they would have to change the way bottom brackets were assembled. The innovation race took off in the cycling industry, but companies failed to agree upon a standard development platform, and rapid development quickly made new technologies obsolete.

Loose Bearing Bottom Brackets

The Birth of the Cartridge

A Shimano square taper bottom bracket with cartridge bearings at left.

Recently, the loose-bearing system is largely being phased out in favor of another system, known as the cartridge bottom bracket. Much less complicated and with a significantly longer lifespan, cartridge bottom brackets basically encase the mechanical workings of the loose bearing bottom bracket into a much simpler, two piece system. A cartridge bottom bracket consists of the cartridge (duh), which screws (or is sometimes pressed, more on that later) into the drive side of the bottom bracket shell and contains the bearings and spindle, and a lockring, which supports the bottom bracket on the non-drive side.

Cartridge bearings contain all the bearings for each side of the bottom bracket in one unit.

This type of bearing assembly is largely the standard for today’s bikes, although there are changes on the horizon, namely in the ultra high-end markets. With a simplified design, overhauls no longer involve tedious inspections of individual bearings, and riders can instead easily and cheaply replace or upgrade the cartridges which hold the bearings.

Threadings and Sizes

While a cartridge bottom bracket may seem straightforward, bottom brackets are not one-size fits all. In order for a standard cartridge bottom bracket to be installed on a frame, the two pieces must be threaded into the bottom bracket shell of the frame. This is where choosing a threaded bottom bracket starts to get tricky, because different frames from different manufacturers have different bottom bracket shell sizes, thread sizes and TPIs (threads per inch.) Most frame manufacturers stick to a few more common threadings, such as British, Italian, French, and Swiss, each of which has their own threading and sizing specs. A majority of frames use English threading (1.37″ X 24 TPI) but Italian branded frames (Colnago, Pinarello, etc.) use a slightly different Italian threading pattern (36mm X 24TPI.) French threading is measured at 35mm X 25.4 TPI. The widths of bottom bracket shells also differ; a 68mm shell width is standard for British and French road frames, and 73mm is standard for British and French mountain frames. Italian frames use a unique 70mm wide bottom bracket shell. In order for a bottom bracket to screw into a frame’s shell, its threading must match perfectly with the shell, so check the threading of your frame before ordering a new bottom bracket. You local bike shop will be able to tell you what type of threading and bottom bracket shell diameter your frame has if you don’t know.

Notice the square interface at the center of these FSA cranks.

Once the bottom bracket is installed, it’s time to attach the cranks. There are several different interfaces, and crankset interfaces must be the exact same as the bottom bracket to attach properly. The square taper spindle was the original interface, where cranks have a square hole and are slid onto the squared ends of the spindle which get thicker as you get closer to the center. Bolts then press the arms further onto the spindle.

ISO vs. JIS

This Miche Primato bottom bracket uses the smaller ISO square taper.

European and Asian manufacturers split when developing their own square taper interfaces, resulting in two standards that survived in the international cycling community. Europe gave birth to the ISO square taper bottom bracket, and Japan developed the JIS, or Japanese Industrial Standard. The two interfaces are remarkably close in dimensions, but the ISO design tapers down to a slightly smaller end. Logically enough, most European brands (Campagnolo, etc) adapted the ISO interface and Asian brands (Shimano, Sugino, etc) stuck with the JIS interface. One interesting note; the Japanese NJS parts highly prized by the fixed gear crowd and used for elite Keirin track races use a European ISO interface, and the parts are threaded to European standards. NJS standards use the same threading as Campagnolo track parts.

Moving Past the Square Taper

From left, a traditional square taper, Shimano Octalink V1, Shimano Octalink V2, and ISIS bottom bracket interfaces.

This was just the beginning of the confusion, because manufacturers eventually began to abandon the square taper interface all together, and proprietary interfaces began to surface from some major component companies as the innovation and marketing bugs began to spread. First onto the market was Shimano with their Octalink Interface. Shimano developed a system which would attach the cranks via a splined interface, with eight grooved splines that would line up with eight inverse splines on the crank, replacing the square taper interface.

The Octalink system had several advantages; it created a stiffer interface, giving the rider more power transfer from their legs into the mechanical system of the bike, much more than a square taper bottom bracket. While Shimano did have a major improvement in bottom bracket technology, they quickly patented it, and charged a licensing fee to any company wishing to use the technology in their products, making it inaccessible and expensive to their competitors and other component manufacturers. Keep in mind that cranksets must be manufactured with an interface to match the bottom bracket, so crankset manufacturers had to pay Shimano if they wanted to make Octalink-compatible cranks.

Some companies jumped on board and paid, while others decided to counter Shimano’s stronghold with the development of an alternative to the Octalink system which could be widely used across the industry as an open development standard, meaning any company would be free to develop products using the technology, thus creating an internationally accepted and accessible standard. So major industry brands King Cycle Group, Truvativ, and Race Face got together to develop the International Splined Interface Standard or ISIS, a system which was similar to Shimano’s but used ten splines instead of the Octalink’s eight. Both interfaces are still widely in use today, but ISIS is generally more popular, because it is more accessible.

Outward Bound

External bottom brackets house the bearings inside of cups outside the bottom bracket shell. Bearings are inside the silver rings between the cranks and the bottom bracket shell in this picture.

By this time, the race was on to develop stiffer, lighter bottom bracket and crank systems. The focus moved away from development of the interface and began to shift toward structurally superior configurations. As innovation continued, engineers soon found they were limited by the diameter of the bottom bracket shell. To improve power, manufacturers were looking to beef up the diameter of their bottom bracket spindles (axles), but in order to do so, the bearing sizes had to be smaller in order to fit the entire configuration inside a standard bottom bracket shell.

Smaller bearings mean less durability, something they weren’t willing to sacrifice, so the spindle size had effectively been maxed out. This problem gave birth to the external bottom bracket system, which moves the bearings of the bottom bracket into cups which sit outside the bottom bracket shell of the frame, allowing for large bearings and a thick spindle within the traditional bottom bracket shell dimensions. Remember that up until this point, in traditional square taper, Octalink, and ISIS set-ups, the spindle and bearings were all housed WITHIN the bottom bracket shell of the frame. Moving the bearings outside the shell created more room for a larger spindle inside, so external bearing bottom bracket systems can have both larger spindles and bearings than their traditional counterparts.

Spindle diameters could suddenly go up to 24mm, which made them stronger and stiffer than ever before. This was a MAJOR improvement, and created a much stiffer crankset/bottom bracket set-up, which is being widely used today. Almost every manufacturer has brought their own brand of external bottom bracket systems to the market; popular models include Shimano Hollowtech II, Race Face X-type, FSA MegaEXO, and Truvativ/SRAM’s Giga X Pipe (GXP). These external bottom brackets are probably the most common type of bottom bracket found on bikes in today’s market. Each brand’s external bottom bracket system is fairly similar, and most have also designed exclusive crank/bottom bracket product lines based on external bearing bottom bracket designs.

It should be noted that Campagnolo’s Ultra Torque crankset/bottom bracket system uses external bearings, but each crank arm is permanently attached to one half of the spindle, and they are joined in the middle of the bottom bracket shell, the only bottom bracket to do so.

Thought that was it? While external bottom bracket systems are still relatively new to the market, there is still more change on the horizon with the BB30 standard. Debuted by Cannondale at the 2000 Tour de France, the BB30 system starts from the frame up, using a larger-diameter bottom bracket shell sizing to create more space for an even larger 30mm diameter axle, 6mm thicker than the 24mm steel axle used on external bearing systems. (The traditional inside shell diameter was 34mm, BB30 uses a 42mm inside diameter.)

The BB30 system is also unthreaded; the bearings are pressed directly into the shell instead of sitting inside of cups threaded into the frame. This saves weight, because it eliminates the need for some parts, like the threaded cups. Even the threads that they require to screw into the shell add some weight.

Similar to the ISIS concept, BB30 is an open standard. Cannondale initially developed it as a proprietary technology, but saw the potential for the set up and wanted to avoid some of the mistakes made by Shimano with their Octalink system. Thus, it was published as an international standard, and is now free for any manufacturer to use and develop.

Many experts in the industry see a bright future for BB30 systems, as they are the stiffest and lightest to hit the market thus far, and perhaps more importantly, the technology is equally available to every company, making it a good contender for worldwide acceptance. As for now, this system is mostly reserved for higher-end bikes. In addition to a new bottom bracket shell, cranks must be manufactured to work with the BB30 system, so options are still limited. SRAM and FSA are some of the early adoptors of this technology. SRAM offers their Force, Red, and XX cranksets with a BB30 option and FSA Gossamer, Afterburner, SL-K and K-Force cranksets also have a BB30 option. While it does provide a significant performance increase, frame and crank manufacturers must design new frames around the larger shell size of the BB30 standard, and it will most likely be a few years before the larger shell specs trickles down frame manufacturers’ product lines.

Some frame manufacturers like Scott, Trek, and Giant have tried to take the BB30 system even further, creating the “integrated bottom bracket.” This system requires yet another new bottom bracket shell sizing, designed around the diameter of bearings in existing external cup bottom brackets. The technology behind BB86/90 systems is similar to BB30, but it is designed to be used with existing external cup, two piece cranksets. Just like BB30, bearings are pressed into the shell, eliminating the need for cups and threads, and again, eliminating more weight. BB86 and BB90 get their names from the width of the shell (86mm and 90mm wide), while BB30 got its name from the 30mm spindle diameter. Shimano’s own adaptation and proprietary interpretation of this technology is called the “Shimano Press Fit” bearing system. Shimano has not yet adapted any of their products to the BB30 system, and is instead investing its resources into its incompatible Press Fit systems.

Lastly come the eccentric bottom brackets, which are used almost exclusively on single speeds, fixed gears, and tandems. These setups allow the bottom bracket to slightly rotate in order to adjust chain tension without moving the rear axle.

Get Your Bearings

Ceramic bearings have made quite a splash in the high-end market recently as a lighter, stronger, and smoother alternative to steel ball bearings. While they do tack on a few extra bucks, most agree that there is a performance increase in ceramic bearings. Some high end models come with ceramic bearings, but aftermarket ceramic bearing cartridges can be purchased in a variety of sizes from several manufacturers.

Looking Ahead

Bottom bracket technology will be a constantly evolving area, and we are most likely rather far from developing a lasting standard. Much like the headset, constant and quick innovation will drive introductions of newer, better standards as engineers develop better products and materials. The bottom bracket wars are far from over, and it seems to be only a matter of time before the current technologies become largely obsolete, giving way to stiffer, lighter, stronger designs.

Take a deep breath. For the moment, anyway, you can consider yourself up to date.

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Thoroughly enjoyed this brief synopsis of the bottom bracket. Would enjoy more similar to this regarding other bike parts/components, etc. Thanks for the education. Matt

Are there any measured numbers, showing how much is “much more” in this case? So that we are all sure here that this is not just a marketing brainwashing 😉

Come on Jeremy, who needs objective data? Probably wouldn’t understand the statistical analysis of the research performed on the material anyway. That’s for grad students who need trivial projects to complete their degree. WIth a little EPO and octalink, the power transfer really is greater. (But you bring up a good point.)

Congratualations, this will make its way to my sidebar links. Thanks Ty.

“The Octalink system had several advantages; it created a stiffer interface, giving the rider more power transfer from their legs into the mechanical system of the bike, much more than a square taper bottom bracket.”

It also broke on several occasions. Here’s an example of a shearing failure : http://pardo.net/bike/pic/fail-001/spindle-fail-001.jpg Supposedly, there was a small amount of torsional backlash in the splines that worked the retaining bolt lose to the point where insufficient engagement cased a rupture. I recall someone’s comment (can’t figure out where I read it) that he crushed a cartridge BB and found the spindle to be stepped down from the diameter at the ends and the bearing race was cut further into the spline. Stress concentrations?

Perhaps not everyone needs a 30mm spindle to begin with. If you’re make like a German sprinter and you know you’re going to pound on that bike every so often, sure. Bigger spindles transfer the same torque with less stresses. If you’re a puny guy simply biking for enjoyment, you don’t necessarily need to shell an extra half grand or whatever it is for fancy bottom brackets.

Very good point, Cozy. It should be noted that there were several reports of Octalink durability problems that hurt its reputation and probably contributed to its eventual downfall. Lots of reports out there of premature wear because of the smaller bearings needed for use with a larger spindle.

The Specialized s-works cranks are another version of the Campy ultra-Torque

I have never seen an Octolink spindle break like that square taper spindle you have posted. Do you have a photo of an Octolink spindle failing in that manner?

The main issues that I am aware with Octolink is spindle/crankarm interface wear.

I agree with beehive. The Shimano splines have a tiny bit of rotational slop which cannot be eliminated no matter how tight the bolt is. Pedaling works the bolts loose on a regular basis and you pretty much have to carry a large hex key with you. I think Shimano made a design blunder by not tapering the splines so that you could achieve a dead-solid fit when the bolt is tightened. that was the nice thing about the square taper system of old. Of course, I don’t think the isis system is tapered either. I personally think they all would benefit from a taper fit spline. It’s a bit more difficult to produce but It makes a better connection.

To Note: BB90 is a Trek only standard that does not use external cups. The bearings (which are spec’ed to fit a 24mm external BB spindle)press directly into the carbon frame similar to a BB30 system except for the fact that a BB90 is “90”mm wide and a BB30 bottom bracket is 68mm wide for road and 73mm for MTB. (also the BB30 bearings are bigger in race OD and ID)

I believe you have BB90 confused with the shimano BB91 (or BB92 in MTB circles) which is a nylon reinforced cup which is pressed into the BB of the frame. The BB91 standard comes in a few widths for BB which are 86.5mm width for road which in the end after the cups are pressed in become 90.5mm (hence BB91?….yah confused yet…just wait) The MTB BB92 kit which either works with a 89.5mm or 92mm width and this depends on whether the manufacturer wanted to run the BB asymmetrical or symmetric due to using a E-type derailluer or not.

So depending on what manufacturers bike you purchase and what BB koolaid they have drank you might want to know this information before you leave the shop and make sure you marker it in on the underside of your top tube…this is so when the poor mechanic/parts counter guy comes to deal with you and a new BB you will at least give him a heads up on what they are dealing with and they can get you set-up in a timely less frustrating manner.

This is a useful article with good pictures.

I agree with most of it and appreciate that it points out the old Ashtabula system was strong. Your department store 10 spd example does not suggest this, but the early BMX bikes with their CrMo one piece cranks and their higher ball-count, more precision, pressed in bottom brackets could take garage roof drops that totally flattened a top quality pair of wheels in one drop. No aluminum set up ever matched that strength.

I do question the use of the term “loose ball” to express what should more accurately be called “three piece” cranks. In fact your own example shows that three piece cranks used the same type of “retainer” bearings as did the Ashtabula.

You can be excused for missing the tangent of hollow BMX crank development including the Red Line Flight system.

Thank you for mentioning the innovations that Cannondale and Alex Pong (Magic Motorcycle) brought to the story.

I do think that missing “cottered cranks” is not acceptable. That is surely the great grand-father to all that has followed.

That cottered crank was the rest of the world’s system at the time Schwinn and all the other American bike manufacturers where using the Ashtabula (ohio,btw) one piece crank. Anyone interested in keeping a classic bike classic might find this necessary information. Working with them can be tricky, the most important things to know is. Drive the pins in, don’t use the treads to pull the pins tight. You probably won’t be able to use a pin once you remove it but by now that might be a necessity. There where about 8 different pin diameters/ and bevel tapers, so matching pins and pins orientation to each other was important. J&B imports still has many of the sizes.

All in all, nice web content. Wish I had done that.

Has anyone had a problem with creaking from bb30. I am purchasing an orbea orca currently have easton ec90 crankset and bottom bracket. Can’t decide whether to us with sleeve or move to SRAM BB30 crankset. Any advice is appreciated

I’ve been riding since the ’60’s, and have seen the up and downsides to the evolution of BB tech especially. The trade-offs between utilitarian/tourist oriented design thought, versus pure racer’s priorities, is a constant source of aggravation. It is my opinion that except for the weight issue, many “advances” have been poorly executed, and the BB is perhaps the worst. The older steel BB spindle and adjustable outer races were notoriously easy to contaminate, and they’d need overhauling after one rain ride. However, the integral sealed unit that was the standard until the “outboard” bearing and large hollow axle, may have been the best with longevity and cost- I’m still riding a mountain bike w/ 10year old Shimano BB, and it spins far more easily and smoothly than either a Campy UT, or an FSA mega-exo w/ Enduro ceramic upgrades. Maybe because the one-piece unit can align and protect the two bearings far more accurately, while the sloppy tolerances of facing the BB shell, along with the klugey methods used to seal and position the newer style make it more likely to have binding, twisting, and side-loading issues regardless of how much better the bearing itself might be. Most have extra washer-like “seals” crammed in between the bearing and the crank arm, but this only seems to be a trap for dirt and water, not a seal at all. The bearings should have minimal side loading, unlike a hub bearing, yet adjusting the final fit involves shims, loctite, etc. and an impossibly accurate facing and width requirement, that unfortunately today one shop in 100 may have the tools and a mechanic who knows what to do wtih them.

The *need* for increased rigidity in the bicycle for most users is debateable to say the least – the *need* of component manufacturers to come up with reasons to encourage unbridled consumption to keep all of those factories out there churning and burning is, however, not at all debateable!

My own feeling as a mechanic and a rider, who spends a lot of his time talking to enthusiast riders, is that many have been seduced by the technology, without considering whether it is the right technology for their purpose. This is true right the way through, from frame design to wheel construction, including (appropriately enough as it is called the “Central Movement” in many languages) the BB.

Many of the technological “advances” that we see are a re-hash with better materials of old ideas, carefully spun to make them attractive to consumers, often implimented to reduce production or assembly time & therefore cost, but often marketed at premium prices in order in part to defray the costs of persuading consumers to make a change.

BB technology, I’d contend, is no different in this respect. The current divergence in choice is not helpful to anyone, and the “advantages” supposedly gleaned are of no practical use to 99.9% of the users out there … it’s easy for those of us involved in the very-serious-leisure-to-racing side of the market to forget that our special interest forms an insanely small part of the market.

I think it’s that element that is missing from the otherwise excellent (even if it does miss out cottered systems) set of notes above.

BTW, you are (sadly) only too right about the durability problems of outboard systems, exacerbated by the lack of tooling / training in the use of that tooling for facing & chasing BB shells … we run a course in frame preparation at my company, and the number of supposedly experienced spanner-monkeys that we have to go back to basics with in terms of concepts like concentricity, parallelism and tolerance in thread design and execution is scary ….

BB91 vs. BB92 Ron, or whoever……. I need a new BB for my 2008 Pivot Mach 5. My shop has a BB91 instead of the spec’d BB92, but Pivot owner Chris Cocalis says it is OK to use BB91.

“….. no issues as long as you do not run the spacer. ”

Is this true? Would you feel cool with the BB91? Doug Local Triad, NC rider.

Are there any adapters that exist that can convert the standard english threaded frame BB housing to use the BB30 crankset?

I have a new set of BB30 cranks but I still want to use my old frame. Any recommended options? Mike

–>Mike – No. BB30 has a 30mm spindle. . . all of the old “standard” (english/italian) bottom bracket styles were built for 24mm spindle.

To play devil’s advocate for the side of new technology (vs. the old traditionalist super shop guys). . . I agree, a lot of the new products out there re-package old ideas and are sold for a higher price. I also believe that a lot of people buy the wrong bike for themselves. . . they see the tour and want the racing style bike when what their legs and back really need is a “paris-roubaix” style bike (or maybe even a hybrid). That being said. . . the amount of trickle down technology that comes through all of the constant performance oriented engineering is significant. The amount of features that a person can buy on a 400 dollar bike today is far beyond what they would have been able to 20 years ago (dollars adjusted for time). I agree that some of the technological advancements do not suit the great majority of riders, but if the rider can slow the purchasing experience, they just may end up with a great bike that borrows a lot of good technology from our performance oriented engineering industry.

ps. I have never had any problems with external bottom brackets. I put them on the bike once (properly), ride hard, in the rain, across the country, pushing my heavy 210 lb body up hills/mountains, and have never heard so much as a creak, let alone had to tighten it or take the whole thing apart.

pss. the only bottom bracket left off of this forum is the new FSA/Wilier/BH BB3865. . . 30mm spindle, 86.5 wide

Excellent article. Did they miss “BBright” or just not call it by name?

Hi, Does anyone know what is the difference between Shimano square taper bottom bracket UN26 and UN54. How to identify the bottom backet on my bike is English thread or Italian thread. Thank in advance.

Regards LEE YW

I have a 1980 DeRosa bike w steel frame, had loose Campy bottom bracket w italian threading…..can I convert this bike to use an Outboard bearing bottom bracket? If so, which options do I have?

Thank for your assistance,

Hello Buy a frameset Scott Plasma Premium and this goes a botton bracket BB91 Press Fit The question is: to continue using my FSA SLK MegaExo Ligth cankset shaft diameter 24 mm. I used these with a botton bracket BB8681 That botton bracket should I buy? I prefer ceramic thanks Marcelo Argentina

Guys please can i have your advice..im using fsa pro team issue cranks and an ISIS BB type. Now, i want the left arm of the crankset fitted or latched snugly like shimano with cups outside the BB shell. I just want to hide the remaining space from it to keep it tidy and neat without seeing a small amount of space on the arm. Is it possible of having those kind of housing in an ISIS BB?

Can you recommend whats best solution please.

Sonny Philippines

My new frame has a BB30 bottom bracket with no threads, but my old one was a regular GXP (BSA?) screw-in type – so despite having a spare BB I’m still stuck.

If I understand correctly, there seems to be various adapters out there (esp. Wheels Manufacturing, and Endura) allowing you either: to press-fit an adapter then screw-in your old GXP BB; or to use regular BB30 bearings then a shim to allow your GXP crank to fit.

Both would let me use my GXP crank on the new frame somewhat more cheaply than an equivalent new SRAM crankset for BB30… but is it worth it? Am I better off biting the bullet and just buying a full BB30 crankset to get the most of my frame?

Thoughts welcome!

following links may be useful to others: http://mikesbikes.com/product/wheels-manufacturing-bb30-bottom-bracket-adaptor-for-gxp-cranks-sku-cr1230-qc129.htm http://blog.artscyclery.com/ask-a-mechanic/ask-a-mechanic-adapting-sram-gxp-to-pf30-bb30-bbright/

Can the article be amended ? to include info on whether the spindle length has to match chainset.

i.e Shimano techdocs state a certain spindle length for a certain chainset but in most cases the length of recommended spindle is different from the previous bottom bracket spindle. Surely chainline will be affected.

Two corrections:

1) You missed out cottered cranks! Their BB axle has a single flat at each end and a tapered flat-sided pin was wedged in against the flat. They were the standard for a great many years in most of the world. North America was much more inclined to the Ashtabula/onepiece crank, I don’t know the history of cottered crank there.

Ignoring the still-substantial share of onepiece cranks, global market share for new cranks was given in 2012 as: 80% square taper 20% cottered, 10% ISIS and all the modern designs. source: http://www.thun.de/fileadmin/user_upload/documents/Glossar/Handout_DIN.pdf

2) French and Swiss BB threading is long-gone. I read that Peugeot switched from French to Swiss to English over the period 1978-1984 or 86, and I know for sure that it was 1984 until all of their top models got English threading in all markets. ————————————————————————- re “Confused – 01/07/13”, on why the recommended modern replacement for an old discrete BB may be longer than the original:

Older cranksets often required a BB which was 1-8mm longer on the drive side. (I guess this was originally to allow use of a single crank casting/forging for both sides, the driveside one then having a spider or chainring swaged onto it). The discrete BB axle will have a code stamped into it e.g. “3P”.

Modern cartridge square BBs are pretty much symmetrical, though some of the longer ones have an extra mm on the drive side. So when replacing an assymmetrical discrete BB you often have to use up to a 2mm spacer on the drive side, which would require a BB 4mm longer than the original to achieve symmetrical pedals. In order of importance consider 1. chainstays – the cranks must not hit. 2. Chainline. 3. pedal symmetry and width apart, which affects your leg joints and cornering clearance.

Feel free to update the original article from this.

A very interesting read indeed, I thought this article would have what i required for a Tandem i bought for £45, as a home project but also to have some fun and ride the London to Bright with a work colleague.

There seems to me there is an interface missing from the article. I have got two bikes where the BB axle has a ‘cut out’ section (not sure of the technical name), to fix a crank to the axle you place the crank over the axle and line up a circular hole in the crank with this ‘cut out’.

Once lined up insert a metal tapered shim and place a bolt on the end which tightens the crank into place, this is what i have on the bike but finding replacement parts is a nightmare at present.

In summary there is no note of this within the article, but it is out there, what is this interface and where did it come from, also where can you get replacement parts (if any)?

Any help would be appreciated, I could just replace the BB and the crank-set, this will not only increase the cost of the project, but detract from the originality and i would prefer to have this.

Okay i did not see the last posting….[embarrassed face], result, read all comments in future.

Thank you Simon White, I have something to go one now and further investigate!!

Nice article, a good read for someone looking outside that branded box.

Just found this great read.. much easier than wikipedia’s article to understand. Could I somehow replace my square taper shimano bb and us a BB30 crankset (sram force)?

QBasso, No, and this article is way out of date at this point.

My Colnago Strada SL frame currently use BB 1.37×24 with shimano ultegra hollowtech 2. My question is : 1. Is it right if i get ISIS BB , i had to choose 73mm English 108mm(road) ? or the 68mm ? 2. If i get an FSA light crank, WHICH FSA crank i had to get in order to install correctly on my frame? BB386 ? MegaExo ? 3.Which crank can get slip inside shimano BB Hollowtech 2 other than shimano crank ?

The beauty of the bicycle – and what gave it acceptance and popularity – was simplicity and serviceability. Not as an experiment, but in the course of overhauling a Raleigh-built 531 road bike, I replaced the bearings (yes, loose) of Dura-Ace BB, hubset, and headset with precision chrome-moly ball bearings (yes, loose) of the correct sizes and packed them with high-load silicone bearing grease. After adjustment, the bike was put back on the road. Two years later, after about 1500 miles of New England riding including hot, cold, and wet days, it seemed time to take a look at the bearings again.

Surprise! In all instances, the bearings and races were immaculate. There was no discernible evidence of metallic shedding (usually noted as a blackening in the grease) nor breakdown from moisture. Again, these were road miles and not particularly aggressive. But the demonstration was that good fundamental design and material quality provided trouble-free cycling at a small fraction of the cost of endless re-engineering.

Today’s cyclists are faced with costly and ever-changing componentry in pursuit of the ultimate in light weight and an intractable proliferation of “standards.” We cyclists and cyclist-mechanics have lost something very special to the sport of recreational cycling. While new designs may, in fact (in engineering and advanced power transmission testing), be improvements for extreme users the benefit to most cyclists is fanciful. Keeping a comfortable cycle operating efficiently and economically has been traded for “the latest” output of a profit-minded manufacturing sector. A shame, really.

Great overview of the bottom bracket quagmire for novice mechanics like myself.

This piece has cleared up a lot of the more confusing aspects of all of the different technologies for me and the historical frame this round-up is built on put everything in an easily graspable context.

Thanks for this, I will now be able to buy myself parts for my bike re-build with a bit less uncertainty.

I have a Giant XTC 27.5 (2014) and now I’m looking to replace the crank. At the moment I have Shimano Deore Hollowtech II. The problem I have is I don’t know how to find out if I have 68/73 or 83 shell width and I can’t find a answer anywhere how to find out what I have. The only information I have been finding is that it exist. The Giant website only say that it is press fit and when I find information about Hollowtech, they only talk about threated brackets and not press fit. How can I, without disassemble the bike, know which shell width I have? Or doesn’t this matter looking at the crank and does this only matter when changing the bracket?

still a good article in 2016 – thanks.

Great reading, and thank you to everyone on the thread as well!!

What bottom bracket shell fits the gt idrive four 1.0?

The problem I have with square-taper fitting is getting the cranks off because the aluminium cranks stick to the steel axle. If I try the standard removal tool which screws into the boss of the crank, all that happens is that the soft aluminium threads in the crank are stripped off. Using a couple of hefty bolts and some bits of old 1/4″ steel I have improvised an extractor, but crank removal is still a major job. I’m going to try an ISIS splined system which I hope will avoid the removal problem.

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Bottom Bracket Basics: Cyclists’ Guide to Standards

Threaded Bottom Bracket Standards

Threaded bottom brackets screw into threads in a bicycle’s frame.

Among the most common standards in the threaded bottom bracket category is the BSA, also known as the English (ENG) standard or ISO. The BSA standard uses 1.37 (34.8mm) x 24 threads per inch, with the non-drivetrain side of the bike threading counterclockwise while the drivetrain side tightens clockwise.

Many bikes made from aluminum or other metals use this option.

Threaded bottom brackets require a special wrench

The T47 is a newer threaded bottom bracket standard. This standard incorporates an adapter of 47mm in diameter x 1mm pitch. The adapters, or “cups,” house the bearings in which a crank spindle turns. These cups screw into the frame the same way as BSA, with the non-drive side spinning clockwise and the drivetrain side turning counterclockwise.

The Italian standard, which features 36mm x 24 threads per inch, isn’t as common, but it is out there. One key difference between the Italian standard compared to the others is that both the drivetrain and non-drivetrain sides turn clockwise.

Threaded bottom brackets tend to be heavier than their press-fit counterparts, as they require more material for threading. However, they have become a godsend for many who work on their bikes because they are far easier to deal with at home.

Press-fit bottom brackets require a tool that can cost hundreds of dollars, while threaded bottom brackets are easy to install or remove with a wrench.

That means threaded bottom brackets can typically be serviced without visiting the local bike shop.

Press-Fit Standards

Press-fit bottom bracket bearings are pressed into the frame where threaded brackets would screw in. They can use cups with outer bearings like threaded counterparts or interior bearings that affix inside a bike frame.

They have a slightly larger diameter than the frame opening, so they hold via pressure and friction. Press-fit bottom brackets require precise manufacturing, as any looseness can result in annoying squeaking.

According to Park Tool , the press-fit legion contains many designs with confusing variations.

“The terminology of press-fit bottom brackets has become especially confusing,” Park Tool says. “Some standards were named for the spindle diameter, others were named for the shell width, and still other terms came from the size of the bore where the press-fit occurs. Because the frame shell bore diameter is the only consistent and most important part of the press fit system, the bore size is the preferred system and will be used here.”

The PF41 standard uses a 41 mm inside diameter. According to Park Tool , this standard also includes the BB86, BB89.5, BB92, BB107, BB121, BB132, PF24, and Shimano Press-Fit.

If those numbers seem confusing, you’re not alone. Here’s how Park Tool explains it all:

“The numbers ranging from 86 to 132 refer to the nominal width of the shell in millimeters, which is not related to the press fit of the bearings. These bottom brackets will vary in the width of the dust sleeve used for that different widths,” according to Park Tool.

“The term ‘Shimano® Press-Fit’ refers to the company that developed bottom bracket components in this standard. The term PF24 is for bearing adapters fitting a 24mm spindle that use a 41mm bore frame.”

The PF 42 standard, like the PF41, is also known as BB30, BB30A, BB30AI, and BBRight Direct Fit. The BB30, which began as a proprietary design from Cannondale, was the first press–fit “standard.” However, the brand decided to open the BB30 for others to use as a more open standard. The BB30A, BB30AI, and BBright have asymmetrical designs.

Since then, Cannondale has created its proprietary BB30A and BB30-83 AI, the BB30A.

The PF46 standard also has many other monickers, including the PF30, PF30A, PF30AI, BB386EVO, OSBB, and BBright Press Fit. PF30 was an early term denoting the difference between the PF46 and PF42 standards. According to Park Tool, the 46 in PF46 comes from the 46mm bore of the frame shell the bottom brackets use.

“The frame shell has a smooth bore with an approximately 46mm inside diameter. The shell widths range in width from 68mm to 86mm,” according to Park Tool.

“The cartridge bearings of the PF46 system use an adapter of plastic or aluminum and are pressed into the bottom bracket shell. Bearing adapters are made to fit different crank spindle diameters, such as 22/24mm, 24mm, 28.99mm, and 30mm.”

Trek released the BB90 and BB95 as its standards in 2007. The bearings are pressed directly into the frame rather than into exterior cups. This created more space in the bottom bracket area of the frame for larger tubes and the increased shell widths of 90mm on road bikes to 95mm on mountain bikes.

Press-fit bottom brackets require expensive tools specifically made for that purpose. They are usually too expensive for a home mechanic to consider purchasing, and misuse can permanently damage a frame.

Bottom Bracket Compatibility

Most of these bottom bracket standards do not work well together. However, they have become so frustrating that many companies have created adapters and accessories to make them function together.

Still, since there is so much variability in the standards, the best way to ensure that the bottom bracket you have your eye on will work is to pay close attention to the exact measurements of each standard — and never assume anything will work without checking first.

Bottom brackets usually garner little attention, as they only become an issue when something goes wrong. But you can save time, energy, and frustration by knowing precisely what you are running before that day ever comes.

Bottom Bracket Basics: Cyclists' Guide to Standards

Bottom bracket "standards" are all over the place. Here's GearJunkie's guide to understanding the quagmire. Read more…

Mark Wilson is a freelance journalist for GearJunkie and BikeRumor. Mark has been writing about cycling, climbing, outdoor events and gear for more than a year. Before that, he spent more than a decade as a journalist at major daily newspapers in Texas covering crime, public safety and local government. Mark spent every free moment during that time carving up singletrack and gravel, or climbing with friends and family in Texas, Colorado and Mexico. Based in Texas, Mark is always looking for new trails, crags and gear to help navigate the outdoors. As a new dad, he is particularly interested in learning how to share his love of the outdoors with his son.

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The Ultimate Guide to Bottom Bracket

A bottom bracket is the part of a bicycle where the cranks are attached to the frame. It is located at the bottom of the frame, hence the name. It is essentially a set of bearings that allow the cranks to rotate smoothly.

The bottom bracket plays an important role in transferring power from the pedals to the rear wheel. When you pedal, the force is transmitted from the pedals to the cranks, and then through the bottom bracket to the rear wheel. A well-functioning bottom bracket ensures that power is transferred efficiently, resulting in a smooth and comfortable ride.

And in the following content, we will walk you through every signle piece of information about this vital bicycle part: bottom bracket, from its types to its a number of standards, and more.

Bottom bracket types: threaded or press fit.

If we categorize the bottom brackets in the way of their installation, we can simply divide them into two different types, ie. the threaded bottom bracket and the press fit bottom bracket.

Threaded Bottom Bracket

The threaded bottom bracket is the older of the two types, and it’s still used in many bikes today. As the name suggests, this type of bottom bracket screws into the frame using threads. The bottom bracket shell of the frame has threads on the inside, and the bottom bracket cups have threads on the outside. The cups thread into the frame, and the spindle of the crankset passes through the bottom bracket.

One of the advantages of a threaded bottom bracket is that it’s relatively easy to install and remove. You only need a few tools, and you can do it yourself. Additionally, threaded bottom brackets have been around for a long time, so there’s a wealth of knowledge and experience out there when it comes to maintenance and repair.

Press Fit Bottom Bracket

The press fit bottom bracket is a newer design that’s become increasingly popular in recent years. Instead of screwing into the frame, this type of bottom bracket is pressed into place. The cups of the bottom bracket are made to fit tightly into the bottom bracket shell of the frame, using friction to hold them in place.

One of the advantages of a press fit bottom bracket is that it can be lighter than a threaded bottom bracket. Additionally, the design can allow for a wider bottom bracket shell, which can lead to a stiffer and more efficient frame. However, press fit bottom brackets can be more challenging to install and remove, and they may require special tools.

How Threaded Bottom Bracket and Press Fit Bottom Bracket Differ

Threaded and press fit bottom brackets differ in a few key ways. Threaded bottom brackets are generally easier to install and remove, while press fit bottom brackets can be lighter and stiffer. However, press fit bottom brackets can be more challenging to install and may require special tools.

When it comes to maintenance and repair, both types of bottom brackets require regular cleaning and lubrication. However, threaded bottom brackets may be easier to service, as there are more options for replacement parts and a wealth of knowledge and experience available.

Bottom Bracket Standard

1. bsa threaded bottom bracket.

BSA threaded bottom bracket is also known as the English threaded bottom bracket. We will learn about it by explaining its two unique mini standards, the ISO threaded internal and external bottom brackets.

ISO Threaded Internal Bottom Bracket

The ISO threaded internal bottom bracket is a standard with a threaded design that screws directly into the bottom bracket shell of the frame. It has a shell inner diameter of 34.8mm and a shell width of 68mm or 73mm. The bearing inner diameter is usually 24mm, but some models may have a 22mm diameter.

One of the benefits of this standard is its compatibility with a wide range of cranksets, including those with a 24mm spindle diameter, such as Shimano Hollowtech II, FSA MegaExo, and SRAM GXP. To install the bottom bracket, you’ll need a bottom bracket tool, which fits into the notches on the cups and allows you to tighten or loosen them.

ISO Threaded External Bottom Bracket

The ISO threaded external bottom bracket is another standard with a threaded design, but instead of screwing directly into the frame, it has cups that thread into the bottom bracket shell. The shell inner diameter is the same as the ISO threaded internal standard, at 34.8mm, but the shell width can vary from 68mm to 100mm.

The bearing inner diameter is also usually 24mm, but some models may have a 22mm or 30mm diameter. This standard is compatible with a wide range of cranksets, such as Shimano Hollowtech II, FSA MegaExo, SRAM GXP, and Campagnolo Ultra Torque.

To install this bottom bracket, you’ll need a bottom bracket tool that fits into the notches on the cups. Once you’ve threaded the cups into the bottom bracket shell, you’ll need to tighten them to the manufacturer’s recommended torque.

Differences between ISO Threaded Internal and External Bottom Brackets

The main difference between the ISO threaded internal and external bottom brackets is the way they attach to the frame. The ISO threaded internal standard screws directly into the bottom bracket shell, while the ISO threaded external standard has cups that thread into the shell.

Another difference is the shell width, which can range from 68mm to 100mm for the ISO threaded external standard, while the ISO threaded internal standard has a fixed shell width of 68mm or 73mm. The ISO threaded external standard is also compatible with a wider range of shell widths and cranksets.

Which Bottom Bracket is Better?

The choice between the ISO threaded internal and external bottom brackets ultimately depends on your bike’s frame and the crankset you plan to use. If your frame has a fixed shell width of 68mm or 73mm, the ISO threaded internal bottom bracket is the way to go. However, if your frame has a wider shell width or you plan to use a different crankset, the ISO threaded external bottom bracket may be a better fit.

2. Italian Bottom Bracket

The Italian bottom bracket is a type of bottom bracket that has a shell inner diameter of 70mm and a shell width of 36mm. The bearing inner diameter is usually 35mm, although there are some variations. This type of bottom bracket is compatible with Italian-threaded frames and cranksets.

The structure of the Italian bottom bracket is different from other types of bottom brackets. It consists of two cups that thread into the frame, and the bearings sit in the cups. The cups are usually made of aluminum, and the bearings can be either cartridge or loose ball.

When it comes to installation, the Italian bottom bracket can be a bit tricky. The cups need to be threaded into the frame in a specific way, and if they’re not installed correctly, you can damage your frame or bottom bracket. It’s best to have this type of bottom bracket installed by a professional.

Differences Between the Italian Bottom Bracket and BSA Threaded Bottom Bracket

The main difference between the Italian bottom bracket and the BSA threaded bottom bracket is their size. The Italian bottom bracket has a larger shell inner diameter and shell width than the BSA threaded bottom bracket. This means that the Italian bottom bracket is not compatible with BSA-threaded frames, and the BSA threaded bottom bracket is not compatible with Italian-threaded frames.

Another difference is the material of the cups. The Italian bottom bracket cups are usually made of aluminum, while the BSA threaded bottom bracket cups are usually made of steel. This can affect the weight of your bike, but the difference is usually negligible.

So, which one is better? It depends on your bike and your preferences. If you have an Italian-threaded frame, you’ll need an Italian bottom bracket. If you have a BSA-threaded frame, you’ll need a BSA threaded bottom bracket.

In terms of performance, there isn’t a significant difference between the two types of bottom brackets. Some cyclists prefer the Italian bottom bracket because it’s less common and adds a bit of flair to their bike. Others prefer the BSA threaded bottom bracket because it’s easier to install and more widely available.

The T47 bottom bracket features a larger diameter than a traditional threaded bottom bracket, which provides a stiffer and more reliable interface between the frame and the crankset. This increased diameter also allows for larger bearings, which can improve durability and reduce friction.

It consists of an aluminum or titanium shell that is pressed into the frame. The shell has an inner diameter of 47mm, which is larger than the 37mm diameter of a traditional threaded bottom bracket. The bearings are then pressed into the shell, and the crankset spindle passes through the bearings. The bearings can either be pressed directly into the shell or into a cup that is then pressed into the shell.

The T47 bottom bracket is available in a variety of configurations, depending on the frame and crankset specifications. Here are some of the key specifications to consider:

Shell inner diameter: 47mm
Shell width: Typically 68mm or 73mm, but can vary depending on the frame
Bearing inner diameter: Typically 24mm or 30mm, depending on the crankset
Compatibility with cranksets: The T47 bottom bracket is compatible with most cranksets that use a 24mm or 30mm spindle diameter, including Shimano, SRAM, and Campagnolo
Installation: The T47 bottom bracket is installed by pressing the shell into the frame and then pressing the bearings into the shell. Some manufacturers recommend using a specific installation tool to ensure proper alignment and torque.

4. Colnago ThreadFit82.5

The Colnago ThreadFit82.5 bottom bracket is a type of bottom bracket standard used in high-end road bikes . It was first introduced by Colnago, an Italian bicycle manufacturer, and has since become a popular choice among cyclists. The ThreadFit82.5 is a press-fit bottom bracket that uses a threaded sleeve, making it easier to install and remove compared to other press-fit systems.

It consists of two threaded cups that screw into the frame’s bottom bracket shell, and a sleeve that connects the two cups. The cups are made of aluminum, while the sleeve is made of steel, making it durable and long-lasting.

The sleeve has two flanges that fit into the cups, ensuring that the bottom bracket stays securely in place. There are also two o-rings that sit between the cups and the sleeve, providing a tight seal to prevent water and dirt from entering the bottom bracket.

This bottom bracket standard has several features that make it stand out from other bottom bracket standards. Firstly, it has a shell inner diameter of 41mm, which is larger than most other bottom brackets. This allows for larger and stiffer bottom bracket axles, resulting in better power transfer and a more efficient ride.

Secondly, it has a shell width of 82.5mm, which is wider than most other bottom brackets. This extra width allows for a wider stance of the crank arms, resulting in better pedaling efficiency and stability.

Finally, the Colnago ThreadFit82.5 bottom bracket has a bearing inner diameter of 24mm, which is the same as most other bottom brackets. This means that it is compatible with most cranksets in the market.

Specifications of the Colnago ThreadFit82.5:

Shell inner diameter: 41mm
Shell width: 82.5mm
Bearing inner diameter: 24mm
Compatibility: Fits most cranksets in the market
Material: Aluminum cups, steel sleeve

5. Truvativ ISIS Overdrive

The Truvativ ISIS Overdrive Bottom Bracket is a standard that has been used on many mountain bikes and road bikes. Its design includes a spindle that connects the crank arms which is inserted through the frame’s bottom bracket shell. This allows the cranks to rotate smoothly, providing power to the bike’s drivetrain.

The Truvativ ISIS Overdrive Bottom Bracket has a few unique features that set it apart from other bottom brackets. One of these features is its oversized spindle, which measures 24mm in diameter. This larger size provides additional stiffness and durability, making it an excellent choice for riders who put their bikes through tough terrain.

It has an inner diameter of 68mm, which is the standard size for most road bikes and mountain bikes. The shell width is 113mm, which is the standard size for mountain bikes. The bearing inner diameter is 24mm, which is the same as the spindle diameter.

It is compatible with a wide range of cranksets. It is specifically designed to work with Truvativ’s own ISIS Drive cranksets, but it can also be used with other brands that use the ISIS Drive standard. The ISIS Drive standard is a splined interface that connects the crank arms to the spindle.

A French bottom bracket is a type of bottom bracket that was commonly used on bikes manufactured in France in the mid-20th century. This bottom bracket standard has a shell inner diameter of 35mm and a shell width of 68mm. The bearing inner diameter is typically 17mm, which is smaller than other bottom bracket standards.

One of the most unique features of a French bottom bracket is the threading. The cups have a 35mm x 1mm thread pitch, which is different from the standard ISO threading used on most bottom brackets. This means that you’ll need specific tools to install and remove a French bottom bracket.

Another feature of a French bottom bracket is the taper on the spindle. The spindle has a JIS taper, which means that it’s not compatible with modern cranksets that use an ISO or BB30 taper. If you’re looking to upgrade your crankset, you’ll need to find one that’s compatible with a JIS taper spindle.

As mentioned earlier, a French bottom bracket has a JIS taper spindle, which means that it’s not compatible with modern cranksets that use an ISO or BB30 taper. However, there are still some cranksets that are compatible with a French bottom bracket. Stronglight, TA Specialites, and Nervar are all brands that make cranksets that are designed to work with a French bottom bracket.

7. Chater-Lea

The Chater-Lea bottom bracket is a British standard that was first introduced in the early 1900s by the Chater-Lea company. It’s a threaded bottom bracket that uses a 1.37″ x 24 TPI thread, which is the same as the BSA (British Standard) standard. However, the Chater-Lea standard has a unique taper on the spindle, which means it’s not interchangeable with other bottom bracket standards.

The Chater-Lea bottom bracket has a distinctive design that sets it apart from other standards. It features a stepped shell with a smaller diameter on the non-drive side and a larger diameter on the drive side. This design allows for a wider bearing stance, which improves the stiffness and durability of the bottom bracket.

The Chater-Lea bottom bracket also has a unique spindle taper. It uses a 1:10 taper, which is shallower than the 2-degree taper used by other standards. This taper provides a more controlled fit between the spindle and crank arm, which improves power transfer and reduces wear and tear.

The Chater-Lea bottom bracket has a shell inner diameter of 1.37″ and a shell width of 68mm or 73mm. The bearing inner diameter is 35mm, which is larger than the 30mm used by some other standards. This larger diameter provides a wider bearing stance, which improves stiffness and durability.

The Chater-Lea bottom bracket is compatible with Chater-Lea cranksets, which are no longer in production. However, it may be possible to use other cranksets with the Chater-Lea bottom bracket if they have a compatible spindle taper.

To install a Chater-Lea bottom bracket, you’ll need a special tool called a Chater-Lea bottom bracket spanner. This tool is used to tighten the bottom bracket cups into the frame. The cups are threaded onto the frame and tightened against each other to secure the bottom bracket in place.

8. Whitworth

The Whitworth bottom bracket is a British standard that was commonly used in the mid-twentieth century. It features a threaded shell that is 1.37 inches in diameter, and a width of either 68mm or 73mm. The threads on the shell are cut to a Whitworth standard, which is different from the more common ISO threading used today.

The Whitworth bottom bracket consists of a drive-side cup, a non-drive side cup, and a spindle that runs through the middle. The cups screw into the frame’s threaded bottom bracket shell, while the spindle connects the two arms of the crankset.

The drive-side cup is typically right-hand threaded, while the non-drive side cup is left-hand threaded. This means that you’ll need to turn the cups in opposite directions to tighten or loosen them. It’s important to note that the threading on a Whitworth bottom bracket is different from ISO threading, so you’ll need specific tools to work on this type of bottom bracket.

The Whitworth bottom bracket has a shell inner diameter of 1.37 inches, which is smaller than the 1.370 x 24 tpi threading used for ISO bottom brackets. The shell width can be either 68mm or 73mm, although the latter is less common. The spindle typically has a diameter of 5/8 inch, or 15.875mm.

When it comes to compatibility with cranksets, the Whitworth bottom bracket is designed to work with cottered cranks. These types of cranks have a tapered square spindle that fits into a matching hole in the crank arm. If you have a cottered crankset, you can use a Whitworth bottom bracket to connect it to your bike frame.

9. O.P.C. Ashtabula

The O.P.C. Ashtabula bottom bracket is a one-piece design, meaning the spindle and crank arms are integrated into a single unit. This design provides increased strength and durability, making it ideal for BMX and freestyle riding. The bottom bracket shell is also wider than other standards, measuring 2-1/4 inches in diameter. This extra width helps to prevent flex and improves the overall stiffness of the bike’s frame.

The O.P.C. Ashtabula bottom bracket consists of a single piece of steel tubing that serves as both the spindle and the crank arms. The spindle is threaded on both ends, allowing it to be screwed into the bottom bracket shell. The crank arms are attached to the spindle with a pinch bolt, which tightens down on the flat section of the spindle to hold them in place.

If you’re looking to install an O.P.C. Ashtabula bottom bracket on your bike, there are a few specifications you’ll need to be aware of. The bottom bracket shell inner diameter is 51.3mm, and the shell width is 68mm. The bearing inner diameter is 51.3mm as well, and the overall spindle length is 169mm.

The O.P.C. Ashtabula bottom bracket is compatible with a variety of cranksets, including those from Schwinn, Huffy, and Murray. However, it is important to note that not all cranksets are compatible with all bottom bracket standards, so it’s important to do your research before making any upgrades to your bike.

10. O.P.C. Fauber

The O.P.C. Fauber bottom bracket is known for its durability and reliability. It’s designed to withstand the rigors of heavy use and rough terrain, making it an ideal choice for mountain bikers and other off-road cyclists. The bottom bracket features a strong, solid construction that helps to reduce flex and improve power transfer.

The O.P.C. Fauber bottom bracket consists of two main parts: the cartridge and the cups. The cartridge contains the bearings and spindle, while the cups are threaded into the bottom bracket shell of the bike frame. The spindle connects the cranks to the bearings, allowing for smooth rotation.

The O.P.C. Fauber bottom bracket is designed to fit frames with a 68mm or 73mm shell inner diameter and a shell width of 110mm. The bearing inner diameter is 24mm, making it compatible with most modern cranksets. The bottom bracket is designed to be easy to install, with the cups threading into the bottom bracket shell by hand.

The O.P.C. Fauber bottom bracket is compatible with a wide range of cranksets, including those from Shimano, SRAM, and Campagnolo. It’s designed to work with 24mm spindles, which are common on modern cranksets. However, it’s important to check the compatibility of your specific crankset before purchasing a bottom bracket.

11. Raleigh

The Raleigh bottom bracket has a unique structure that is different from other bottom brackets on the market. It features a shell inner diameter of 34mm and a shell width of 68mm. The bearing inner diameter is 24mm, and it uses sealed cartridge bearings.

One of the most significant features of the Raleigh bottom bracket is its durability. It is a reliable component that can last for years with proper maintenance. The sealed cartridge bearings offer excellent protection against dirt, water, and other contaminants that can cause damage to the bottom bracket.

The Raleigh bottom bracket is compatible with square taper cranksets. It is not compatible with other types of cranksets, such as Shimano Octalink or ISIS Drive. It is essential to ensure that you have the correct type of crankset before purchasing a Raleigh bottom bracket.

12. BB86 and BB92

The BB86 and BB92 standards are both designed for use with press-fit bottom brackets. The main difference between the two is the width of the shell. The BB86 has a shell width of 86mm, while the BB92 has a shell width of 92mm.

The BB86 and BB92 bottom brackets have a similar structure. They both consist of two cups that are pressed into the frame. The cups hold the bearings, which support the crankset.

Specifications of BB86 and BB92

Shell Inner Diameter: Both BB86 and BB92 have a shell inner diameter of 41mm.
Shell Width: The BB86 has a shell width of 86mm, while the BB92 has a shell width of 92mm.
Bearing Inner Diameter: The bearing inner diameter for both BB86 and BB92 is 24mm.
Compatibility with Cranksets: The BB86 and BB92 are compatible with most Shimano and SRAM cranksets.
Installation: Installing a BB86 or BB92 bottom bracket is relatively easy. First, clean the inside of the bottom bracket shell and apply a thin layer of grease. Then, press the cups into the frame using a headset press. Finally, install the crankset and adjust the bearings if necessary.

13. Trek BB90 and Trek BB95

The Trek BB90 and Trek BB95 bottom bracket standards are both designed to be lightweight and efficient. They use a press-fit design that eliminates the need for heavy metal cups, which reduces the weight of the bottom bracket and allows for a larger diameter spindle. The larger spindle diameter provides more space for bearings, which improves the stiffness and durability of the bottom bracket.

The Trek BB90 and Trek BB95 bottom bracket standards both use a press-fit design that allows the bottom bracket bearings to be pressed directly into the frame. The bearings are housed in composite or aluminum cups that are designed to fit snugly into the bottom bracket shell. The bottom bracket shell has an inner diameter of 37mm for the Trek BB90 and 37.5mm for the Trek BB95, and a width of 90mm or 95mm, depending on the specific bicycle model.

The Trek BB90 and Trek BB95 bottom bracket standards have some specific specifications that are important to consider when choosing a crankset. The bearing inner diameter for the Trek BB90 is 37mm, while the bearing inner diameter for the Trek BB95 is 37.5mm. These specifications are important to consider when choosing a crankset because they determine the compatibility of the bottom bracket with the crankset.

The Trek BB90 and Trek BB95 bottom bracket standards are compatible with a wide range of cranksets. However, it is important to choose a crankset that is designed to work with the specific bottom bracket standard. The Trek BB90 is compatible with Shimano, FSA, and Bontrager cranksets, while the Trek BB95 is compatible with SRAM, Truvativ, and Bontrager cranksets.

The installation of the Trek BB90 and Trek BB95 bottom bracket standards is relatively straightforward. The bearings are pressed directly into the frame, and the cups are then pressed into the bearings. The crankset is then installed onto the spindle and tightened to the appropriate torque specifications. It is important to follow the manufacturer’s instructions carefully when installing a bottom bracket to ensure that it is installed correctly and functions properly.

14. Look BB95

The Look BB95 bottom bracket is a press-fit standard that was introduced by Look in 2009. It features a two-piece design, with the non-drive side cup being permanently attached to the frame. The drive-side cup can be removed, making it easy to service the bottom bracket.

The Look BB95 standard has a shell inner diameter of 37mm, which is larger than the standard BB30 standard. The shell width is 95mm, which is wider than the BB30 and narrower than the PF30. The bearing inner diameter is 24mm, which is the same as the Shimano Hollowtech II and other popular cranksets.

The Look BB95 is compatible with Look’s own Zed and Trilobe cranksets, as well as Shimano’s Hollowtech II and other cranksets with a 24mm spindle diameter. It is not compatible with SRAM cranks, which have a 22mm spindle diameter.

Installing the Look BB95 bottom bracket requires a special tool, which can be purchased from Look or a bike shop. The cups are pressed into the frame using the tool, making sure they are aligned properly. The bearings are then installed into the cups, and the crankset is fitted onto the spindle.

15. Wilier BB94

The Wilier BB94 bottom bracket features a unique design that includes a shell with an inner diameter of 41mm and a width of 86.5mm. The bottom bracket is designed for use with press-fit bearings, which are pressed into the frame’s bottom bracket shell. The bearings used in the Wilier BB94 have an inner diameter of 24mm.

The Wilier BB94 bottom bracket is compatible with many different types of cranksets, including those made by Shimano and SRAM. When choosing a crankset for use with the Wilier BB94, it’s important to make sure that the crankset has a 24mm spindle diameter.

16. Specialized Alloy OSBB

Specialized Alloy OSBB stands for Oversized Bottom Bracket, a bottom bracket standard developed by Specialized Bicycle Components. It features a larger shell inner diameter of 46mm and a shell width of 68mm. This design provides a stiffer and more responsive ride by allowing for a larger diameter down tube and seat tube.

The Specialized Alloy OSBB has several features that make it stand out from other bottom bracket standards. These include:

Oversized shell: The OSBB has a larger shell inner diameter of 46mm, which makes it stiffer and more robust.
Lightweight: The OSBB is made of high-quality alloy, making it lightweight and durable.
Compatibility: The OSBB is compatible with a wide range of cranksets, making it a versatile bottom bracket standard.
Easy to install: Installing the OSBB is relatively easy, and you don’t need any special tools to get the job done.

Specifications of Specialized Alloy OSBB:

Shell inner diameter: 46mm
Shell width: 68mm
Bearing inner diameter: 30mm

The Specialized Alloy OSBB is compatible with a wide range of cranksets, including Shimano, SRAM, and Campagnolo. However, it’s essential to check the manufacturer’s specifications to ensure compatibility before purchasing a crankset.

17. Specialized Carbon OSBB

The Specialized Carbon OSBB bottom bracket standard is designed to offer a lightweight and stiff structure that maximizes power transfer in the bike. This bottom bracket standard is made of carbon fiber, which makes it strong and durable while keeping the weight low.

The Specialized Carbon OSBB bottom bracket standard has a shell inner diameter of 42mm and a shell width of 61mm. It’s compatible with a bearing inner diameter of 30mm and is designed to fit a wide range of cranksets, including those from Shimano, SRAM, and Campagnolo.

The Specialized Carbon OSBB bottom bracket standard is compatible with a wide range of cranksets, including those from Shimano, SRAM, and Campagnolo. It’s also compatible with different frame materials, including carbon fiber, aluminum, and steel.

Specialized Carbon OSBB vs Alloy OSBB: Which is better for your bike?

The main difference between the Carbon and Alloy OSBB bottom brackets is the frame material they are designed for. The Carbon OSBB is designed for carbon fiber frames, while the Alloy OSBB is designed for aluminum frames. This means that you cannot use an Alloy OSBB bottom bracket on a carbon fiber frame, and vice versa.

Another difference is the shell diameter and width. The Carbon OSBB has a larger diameter and width, which makes it stiffer and lighter. The Alloy OSBB has a smaller diameter and width, which makes it more compatible with standard BSA threaded bottom brackets.

The inner diameter of the bottom bracket is also different. The Carbon OSBB has an inner diameter of 30mm, while the Alloy OSBB has an inner diameter of 24mm. This means that the Carbon OSBB is compatible with most modern cranksets, while the Alloy OSBB is limited to Shimano and SRAM cranksets.

But which one is better? There is no clear winner when it comes to the Carbon vs. Alloy OSBB bottom brackets. It all depends on your bike frame and personal preferences.

If you have a carbon fiber frame, then the Carbon OSBB is the way to go. It’s lighter and stiffer, which will improve your bike’s performance. If you have an aluminum frame, then the Alloy OSBB is the better option. It’s more compatible with standard BSA threaded bottom brackets and is easier to find replacement parts for.

BB30 is a bottom bracket standard that was first introduced by Cannondale in 2000. It has become a popular choice among cyclists due to its light weight, stiffness, and efficiency. The BB30 system consists of a 42mm diameter shell with no threads, and bearings pressed directly into the frame. The shell width is 68mm for road bikes and 73mm for mountain bikes.

Features of BB30:

Shell inner diameter: 42mm
Shell width: 68mm for road bikes, 73mm for mountain bikes
Crankset compatibility: BB30-specific cranksets or adapters for other cranksets
Installation: Press-fit bearings into the frame

Advantages of BB30:

Lightweight: BB30 bottom brackets are lighter than traditional threaded bottom brackets.
Stiffness: The larger diameter of the bottom bracket shell and spindle result in a stiffer and more efficient power transfer.
Wide crankset compatibility: BB30 bottom brackets are compatible with a wide range of cranksets, including BB30-specific cranksets and adapters for other cranksets.

Disadvantages of BB30:

Installation: Installing a BB30 bottom bracket requires special tools and expertise, which can be costly.
Noise: BB30 bottom brackets can be noisy due to the lack of threads holding the bearings in place.

BB30 vs Specialized OSBB: Which is Better?

When it comes to BB30 vs Specialized OSBB, both standards offer similar advantages and disadvantages. The key difference is in the shell diameter, with BB30 using a 42mm diameter shell and Specialized OSBB using a 61mm diameter shell. This means that Specialized OSBB bottom brackets are only compatible with Specialized OSBB-specific cranksets or adapters for other cranksets, while BB30 bottom brackets are compatible with a wider range of cranksets.

In terms of stiffness and efficiency, both standards are comparable and offer a noticeable improvement over traditional threaded bottom brackets. The choice between BB30 and Specialized OSBB ultimately comes down to personal preference and compatibility with your bike and crankset.

19. Cannondale BB30A and BB30-83 Ai

The BB30A and BB30-83 Ai bottom bracket standards share some similarities, but also have distinct differences. Both standards use a 30mm spindle and oversized bearings to reduce weight and increase stiffness. However, the BB30A has a larger shell inner diameter of 42mm compared to the standard BB30’s 68mm. This allows for a wider stance of the frame’s down tube and seat tube, improving stiffness and handling.

The BB30-83 Ai, on the other hand, features an asymmetric offset chainring that is shifted outward by 6mm. This allows for a more even spoke tension between the drive and non-drive sides of the wheel, resulting in a stronger and more stable rear wheel. The BB30-83 Ai also has a wider shell width of 83mm, which is necessary to accommodate the offset chainring.

The BB30A has a shell inner diameter of 42mm and a shell width of 73mm. It is compatible with any crankset designed for the BB30 standard, which includes most modern road and mountain bike cranksets. The BB30A is installed by pressing the bearings directly into the frame’s bottom bracket shell. Cannondale recommends using a headset press tool to ensure proper installation.

The BB30-83 Ai has a shell inner diameter of 46mm and a shell width of 83mm. It is only compatible with Cannondale’s Ai (Asymmetric Integration) cranksets, which are designed to work with the offset chainring. The BB30-83 Ai is installed using a special tool that threads into the bottom bracket cups and pulls them into the frame.

The PF30 bottom bracket standard is a type of bottom bracket that was designed to improve upon the BB30 standard. It was introduced by Cannondale in 2007 and has since been adopted by many other bike manufacturers. The “PF” in PF30 stands for “PressFit,” which means that the bearings are pressed into the frame rather than being threaded in like in a traditional bottom bracket.

One of the key features of the PF30 bottom bracket is its larger shell inner diameter of 46mm, as compared to the 42mm diameter of the BB30. This allows for a larger diameter of the spindle, which increases stiffness and reduces flex. The shell width of the PF30 bottom bracket is 68mm for road bikes and 73mm for mountain bikes. The bearing inner diameter of the PF30 bottom bracket is 30mm, which is the same as the BB30.

The PF30 bottom bracket is compatible with a wide range of cranksets, including those from SRAM, FSA, and Shimano. However, it is important to note that not all cranks are compatible with the PF30 bottom bracket. Make sure to check the manufacturer’s specifications before purchasing a new crankset.

Differences between PF30 and BB30

The main difference between the PF30 and BB30 bottom brackets is the way that the bearings are installed. In a BB30 bottom bracket, the bearings are pressed directly into the frame, while in a PF30 bottom bracket, the bearings are pressed into cups that are then installed into the frame. This makes the PF30 bottom bracket slightly heavier than the BB30, but it also makes it more durable.

Another difference between the two bottom brackets is the shell inner diameter. As mentioned earlier, the PF30 has a larger shell inner diameter than the BB30. This allows for a larger spindle diameter and increased stiffness.

When it comes to which bottom bracket is better, it really depends on your personal preferences and needs. The PF30 bottom bracket is more durable than the BB30, but it is also slightly heavier. On the other hand, the BB30 is lighter but may not be as durable in the long run.

Ultimately, the decision comes down to what type of riding you’ll be doing and what your priorities are. If you’re a competitive cyclist looking for the lightest possible setup, the BB30 might be the way to go. If you’re more concerned with durability and long-term performance, the PF30 might be a better choice.

21. BBRight (Press-Fit)

As a cycling enthusiast, you’re likely aware of the importance of a bottom bracket in your bike’s overall performance. That’s why it’s crucial to understand the different types of bottom bracket standards available on the market. In this article, we’ll take an in-depth look at the BBRight (press-fit) bottom bracket standard.

The BBRight (press-fit) bottom bracket was developed by Cervelo in collaboration with FSA. It was designed to improve stiffness, reduce weight, and increase durability. Here are some of its key features:

Shell Inner Diameter: 42mm
Shell Width: 79mm
Bearing Inner Diameter: 30mm
Bearing Type: Press-fit
Crankset Compatibility: BBRight (press-fit) cranksets

The BBRight (press-fit) bottom bracket has a wider shell than the standard bottom brackets, which provides more space for the bearing to fit. The larger diameter of the BBRight (press-fit) bottom bracket axle also increases stiffness and reduces weight. The bottom bracket is pressed into the frame, which eliminates the need for threads.

The BBRight (press-fit) bottom bracket is compatible with BBRight (press-fit) cranksets, which have a 30mm spindle diameter. Some popular brands that offer BBRight (press-fit) cranksets include FSA, Rotor, and Praxis.

Advantages of BBRight (Press-Fit) Bottom Bracket

The BBRight (press-fit) bottom bracket offers several advantages over the traditional bottom bracket standards. Some of the benefits include:

Increased stiffness and durability due to the wider shell and larger diameter axle
Reduced weight due to the elimination of threads
Improved power transfer due to the increased stiffness
Reduced maintenance due to the press-fit design

22. BBRight (Direct-Fit)

The BBRight (Direct-Fit) bottom bracket standard was developed by Cervelo as an alternative to other bottom bracket standards. It features a wider bottom bracket shell than traditional bottom brackets, which allows for better power transfer and stiffness. The bottom bracket bearings are pressed directly into the frame, eliminating the need for external cups.

The BBRight (Direct-Fit) bottom bracket standard has a shell inner diameter of 46mm and a shell width of 79mm. The bearing inner diameter is 24mm, which is the same as a Shimano Hollowtech II bottom bracket. This means that BBRight (Direct-Fit) bottom brackets are compatible with most Shimano Hollowtech II cranksets.

Difference between Press-Fit and Direct-Fit

There are two main types of bottom brackets: press-fit and direct-fit. Press-fit bottom brackets use external cups that are pressed into the frame, while direct-fit bottom brackets have the bearings pressed directly into the frame.

One advantage of press-fit bottom brackets is that they can be easier to install and remove than direct-fit bottom brackets. However, they may be more prone to creaking and require more maintenance. Direct-fit bottom brackets, on the other hand, can provide better power transfer and stiffness, but may be more difficult to install and remove.

23. BB386EVO

BB386EVO is a bottom bracket standard that was introduced by FSA (Full Speed Ahead) in 2011. It is an evolution of the BB30 standard, which was developed by Cannondale. The BB386EVO standard aims to combine the best features of BB30 and press-fit bottom brackets, resulting in a system that is lightweight, stiff, and durable.

The BB386EVO bottom bracket standard is known for its excellent features that make it a preferred choice for many cyclists. Here are some of its most notable features:

Lightweight: BB386EVO is designed to be lightweight, thanks to its large spindle diameter and thin-wall bearings. This results in a system that is up to 100 grams lighter than other bottom bracket standards.
Stiff: BB386EVO features a wide bottom bracket shell (86.5mm) that provides a larger surface area for the down tube to attach to, resulting in a stiffer frame.
Durable: The BB386EVO bottom bracket standard uses oversized bearings that are designed to last longer and require less maintenance.

The BB386EVO bottom bracket standard has a unique structure that sets it apart from other bottom bracket standards. Here’s a breakdown of its structure:

Shell inner diameter: BB386EVO has a shell inner diameter of 46mm, which is larger than other bottom bracket standards like BB30 (42mm) and BSA (34.8mm).
Shell width: The BB386EVO bottom bracket shell is 86.5mm wide, which is wider than BB30 (68mm) or BSA (68/73mm).
Bearing inner diameter: The BB386EVO bottom bracket uses oversized bearings with a 30mm inner diameter, which is the same as the BB30 standard.

One of the advantages of the BB386EVO bottom bracket standard is its compatibility with a wide range of cranksets. Here are some of the compatible cranksets:

FSA K-Force Light BB386EVO crankset
SRAM Red BB386EVO crankset
Shimano Dura-Ace BB386EVO crankset
Campagnolo Record BB386EVO crankset

24. BB392EVO

BB392EVO is a bottom bracket standard developed by Praxis Works, a company that specializes in drivetrain components. The standard was introduced in 2013 as a replacement for the BB30 bottom bracket standard, which was widely used in the cycling industry. BB392EVO is a press-fit bottom bracket that is designed to fit a 392mm wide bottom bracket shell with a 30mm spindle.

BB392EVO comes with several features that make it a popular choice among cyclists. The bottom bracket is stiffer, stronger, and more durable than other bottom bracket standards. It is also compatible with a wide range of cranksets, including Shimano, SRAM, and Campagnolo. The bottom bracket is available in a variety of colors, allowing riders to customize their bikes according to their preferences.

BB392EVO has a two-piece design that consists of a drive-side cup and a non-drive-side cup. The cups are pressed into the bottom bracket shell and held in place by a snap ring. The drive-side cup has a built-in spacer that allows the bottom bracket to fit frames with either a 68mm or 73mm shell width. The non-drive-side cup has a standard 42mm diameter, which is compatible with most cranksets.

BB392EVO has a shell inner diameter of 46mm and a shell width of 86.5mm. The bearing inner diameter is 30mm, which is compatible with cranksets that have a 30mm spindle. The bottom bracket is compatible with frames that have a 392mm wide bottom bracket shell. The bottom bracket weighs approximately 97g, making it one of the lightest press-fit bottom brackets available.

25. Spanish

The Spanish bottom bracket standard is a type of bottom bracket that is commonly used in BMX bikes. It is known for its durability and stiffness, which makes it ideal for BMX riding.

The Spanish bottom bracket standard consists of a spindle, two bearings, and two bearing cups. The spindle has a diameter of 19mm, which is smaller than the 22mm diameter used in other bottom bracket standards.

The bearings are pressed into the bearing cups, which are then threaded into the bottom bracket shell of the frame. The bearing cups have an inner diameter of 37mm and a shell width of 68mm.

The Spanish bottom bracket standard has a shell inner diameter of 37mm and a shell width of 68mm. The bearing inner diameter is also 19mm, which means it is only compatible with cranks that have a 19mm spindle diameter.

The Spanish bottom bracket standard is only compatible with cranks that have a 19mm spindle diameter, which is smaller than the 22mm diameter used in other bottom bracket standards. This means that you need to make sure that the cranks you choose are compatible with the Spanish BMX bottom bracket standard before you buy them.

Why There Are so Many Bottom Bracket Standards

If you are a cycling enthusiast like me, you might have wondered why there are so many bottom bracket standards. I mean, come on, wouldn’t it just be easier if there was only one standard for all bikes? But the reality is that there are good reasons why there are so many bottom bracket standards, and it’s not just to make our lives harder.

The bicycle industry is constantly evolving, and this is especially true when it comes to bottom bracket standards. Over the years, we have seen numerous bottom bracket standards, each with its own unique design and specifications. For example, some of the most common bottom bracket standards include BSA, BB30, PF30, BB86/92, and BB386EVO. But why are there so many standards? Well, the answer is simple: each standard is designed to meet specific requirements and needs.

One of the main reasons why there are so many bottom bracket standards is that different types of bikes require different standards. For example, road bikes, mountain bikes, and track bikes all have different bottom bracket needs. Road bikes, for instance, require a narrower bottom bracket to maintain the bike’s aerodynamics. On the other hand, mountain bikes require a wider bottom bracket to provide more clearance for the larger tires. So, if we were to unify the bottom bracket standard, it would not be possible to meet the specific needs of each type of bike.

Another reason why there are so many bottom bracket standards is advancements in technology. As technology evolves, so do the materials and designs used to create bike components. For example, carbon fiber frames require a different bottom bracket standard than aluminum frames. As such, manufacturers must create new bottom bracket standards to accommodate these advancements.

Competition among manufacturers is also a driving factor behind the many bottom bracket standards. Each manufacturer wants to create a unique selling point for their bikes, and having a unique bottom bracket standard is one way to do that. While this can make things confusing for consumers, it also drives innovation and keeps the industry moving forward.

While it might seem like unifying the bottom bracket standard would make things easier, it’s not the best solution. As we mentioned earlier, different types of bikes require different bottom bracket standards. Unifying the standard would mean compromising on the specific needs of each type of bike. Additionally, unifying the standard would take time and money, and it’s unlikely that all manufacturers would agree on a single standard.

Bottom Bracket Installation

1. Threaded Bottom Bracket Installation

If your bike has a threaded bottom bracket shell, installing a new bottom bracket is relatively simple. First, remove the old bottom bracket by using a bottom bracket tool. Then, grease the threads of the new bottom bracket and insert it into the shell. Tighten the bottom bracket cups with a bottom bracket tool, making sure they are snug but not too tight.

2. Press-Fit Bottom Bracket Installation

Press-fit bottom brackets are becoming more popular in modern bikes. To install a press-fit bottom bracket, first, remove the old bottom bracket by using a bottom bracket tool. Then, clean the bottom bracket shell and insert the new bottom bracket cups. Use a bearing press tool to press the bearings into the cups until they are flush with the frame. Finally, install the crankset and tighten the bolts to the manufacturer’s torque specifications.

Beside, please remember that a poorly maintained or damaged bottom bracket can affect the performance and safety of your bike. If the bearings are worn out or damaged, it can cause the cranks to wobble, making it difficult to pedal. This can also lead to the cranks seizing up, which can be dangerous if you are cycling at high speeds. So the skils of how to maintain and replace (when necessary) a bootm bracket have to be put into your pocket.

Maintaining a Bottom Bracket

Regular maintenance is essential to keep your bottom bracket functioning properly. Here are some tips to help you maintain your bottom bracket:

Clean and lubricate: Regularly clean and lubricate the bottom bracket to prevent dirt and grime from affecting its performance.
Tighten bolts: Check the bolts that hold the bottom bracket in place and make sure they are tightened properly.
Replace worn out parts: If you notice any signs of wear and tear, such as cracks, rust, or grinding sounds, it is time to replace the bottom bracket.
Seek professional help: If you are not confident in maintaining your bottom bracket, seek the help of a professional bike mechanic.

When to Replace a Bottom Bracket

The first thing you need to know is how to recognize when your bottom bracket is worn out. Here are some common signs:

Grinding or clicking noise when pedaling
Resistance or difficulty pedaling
Play or looseness in the cranks
Uneven or rough pedaling
Uneven wear on the chainrings and cogs

If you notice any of these signs, it’s likely that your bottom bracket needs replacing. However, it’s always best to have a professional bike mechanic inspect your bottom bracket to confirm the diagnosis.

As a general rule, most bottom brackets last anywhere from 2,000 to 5,000 miles. However, if you’re an aggressive rider who likes to tackle tough terrain or frequently rides in wet or muddy conditions, your bottom bracket may wear out more quickly.

Another factor to consider is the type of bottom bracket you have. There are several types, including square taper, external threaded, press-fit, and more. Each type has a different lifespan, so it’s important to check your bike’s manufacturer’s recommendations for when to replace your bottom bracket.

While there’s no surefire way to prevent your bottom bracket from wearing out, there are a few things you can do to extend its lifespan:

Keep your bike clean and well-maintained. Regularly clean and lubricate your chain and other moving parts to reduce wear and tear on your bottom bracket.
Avoid riding in wet or muddy conditions. Water and dirt can damage the bearings in your bottom bracket, causing it to wear out more quickly.
Inspect your bottom bracket regularly. Check for any signs of wear or damage, such as cracks or rust, and have a professional bike mechanic inspect it at least once a year.

Randy Joycelyn

BBInfinite Trek BB90 Bottom Bracket Solutions

December 27, 2022

Don't listen to the Trek BB90 haters. BB90 is the absolute lightest and stiffest bottom bracket system available, and when you do things the BBInfinite way, BB90 becomes the quietest and highest performance bottom bracket system as well. No matter which Trek you own, be it the mighty Madone, the snappy yet comfy Emonda, the cobble gobbling Domane, the cross-crushing Boone, or the trail-blazing Crocket, BBInfinite has the lightest, quietest, stiffest, most durable, lowest friction BB90 system you can buy. FAQ: WHETHER YOU'RE FIXING A BOTTOM BRACKET CREAK OR YOU'RE LOOKING FOR PERFORMANCE ENHANCEMENT, BBINFINITE HAS EXACTLY WHAT YOU NEED. Product Selection Section: Which type of bottom bracket module do I need?? Email us at [email protected] and let know the bicycle frame type (e.g. road), frame manufacturer, frame model / year, and crank type (manufacturer and model). With this information we'll reply with a link directly to the product you need. Attach a few pictures showing the crank and bottom bracket area clearly, and one of the entire bicycle to aid us in our quest to get you on the right track. Creaking Bottom Bracket Section My bottom bracket is creaking and I've tried everything to fix it. How does a BBInfinite Bottom Bracket module fix a creaking problem? We fit creaking bottom brackets with proper engineering and precision machining. Watch this brief BBInfinite primer PressFit Perfection to get the lowdown on how we do it while all others fail. I heard that PressFit bikes just creak. Is that true? No, that is completely false information. PressFit bottom brackets offer the potential for the highest level performance possible, thanks to BBInfinite. There is no reason for your PressFit bike to creak, crunch, crack, or make any noises at all. Unless the frame is cracked the bike will be quiet. Can a creaking and popping bottom bracket damage my frame? Yes, it can. A creaking bottom bracket means there's movement between the bottom bracket and the frame. The more a bottom bracket creaks the more it is moving. This movement over time can wallow out the frame bottom bracket shell openings, enlarging them and elongating them, making them more susceptible to creaking and making it impossible to fit new bottom brackets. Don't freak out, it takes a long time. We've seen only a handful of bikes go in the junk heap due to bottom bracket shell ovalization. Install a BBInfinite module to save your frame, and your sanity. General Bottom Bracket Information Section How much do the modules weigh? Each module model has its weight published under the product description. Go to the BBInfinite bottom bracket page for the type of bottom bracket you desire and you'll find a series of tabs in the product description area. The "info" tab is open already. The last tab "specifications" is where you'll find the product weight along with it's external dimensions. Do all BBInfinite Modules have bushings in the middle? No. Only modules designed for a 30mm spindle require a bushing due to variances in 30mm crank set design and "set up" from one manufacturer to another. These inconsistencies are mostly in the area of preload adjustment methods that put too much side load on the bearings. These over-preloading situations require the use of a bushing between the inner races of each bearing to ensure proper performance. Shimano DirectFit and Campagnolo DirectFit models do not need a bushing. GXP modules have a short bushing that reduces the bearing diameter on one side, but it is not a full length version found on BBInfinite 30mm crank spindle models. Can I use adaptors with a BBInfinite Module? We'd rather you didn't. Technically, it is possible, but such action departs from the basic principles of BBInfinite engineering methodology. Adaptors cause creaks and bearing alignment problems, and are unnecessary when you can select the proper BBInfinite Module for your frame and crank set for a creak-free, high performance riding experience. How long do the bearings last? It varies. Road applications typically last 8,000-12,000 miles for steel bearings and 8,000-12,000 miles for Ceramitech bearings. MTB applications are entirely dependent upon conditions, especially water exposure. Example: A Category 1 MTB racer can usually go an entire season, racing a full schedule, on a single set of bearings of either type. Ceramitechs are better in wet conditions due to a high degree of corrosion resistance. Will a BBInfinite Module work with my power crank/power meter? Absolutely. We designed them specifically to be compatible with even the somewhat troublesome-to-fit older model SRM cranks. BBInfinite Modules are compatible with all power cranks/power meters. Are BBInfinite Modules compatible with my Rotor Qrings / Osymetric rings? Absolutely. BBInfinite Modules are compatible with all chain rings; be they round, not-so-round, or almost square.

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Bottom Bracket Selection Guide

Your Definitive Road Bike Bottom Bracket Guide (Incl E-bikes)

by Johnson Li

The last few decades has seen an enormous increase in the range of road bike bottom bracket designs.

I take a look at the most well-known—and a few not so well-known.

I also take a look at a key development with huge implications for the road bike bottom bracket, as we know it, namely the rise (and immanent dominance) of e-road bikes which, in the mid-drive versions, eliminates the bottom bracket .

More than a minor re-imagining of this crucial bike component, the e-bike revolution may well be the end of the road…

I cover these questions and more in this reflection on the past, present, and especially the future of the road bike bottom bracket.

CONTENTS Threaded: English , Italian , Eccentric , Other Press Fit Brand-Specific Road Bike BBs (Trek, Cannondale, What Does the Surge in Mid-Drive E Road Bikes Mean for BBs?

The THREADED ROAD BIKE BOTTOM BRACKET

The design history of road bike bottom brackets is as simple as you can get. Categorically speaking, anyway.

We began with threaded BBs, ‘progressed’ to press fit, and have recently seen the beginnings of what looks like the return of the threaded BB in T47.

The first road bike model to sport a bottom bracket was John Starley’s 1885 Rover Safety Bicycle, the design that’s still with us today; the BB installed into the frame with threads.

Although there are a number of threaded standards in existence, the English standard is the most common.

The English threaded bottom bracket, otherwise known as the B SA bottom bracket, was — and arguably still is — the most simple and reliable road bike bottom bracket, easy to install, remove, and maintain.

‘BSA’ is the acronym for the Birmingham Small Arms Co. Established in 1861, they got into producing bike components 20 years later and enjoyed many decades in the forefront of components manufacturing (Sturmey Archer came from BSA) before eventually disappearing by the 1970s.

The spec is 24 TPI inscribed into a 34.8mm outer diameter that threads into a corresponding BB shell, with a left hand thread on the drive side (lefty-tighty, righty-loosey).

‘BSA’ BBs mostly appear in the form of cartridge BBs labelled as 1.37” x 24TPI. If you see that, you know you’ve got the right one.

Italian threaded BBs are uncommon. They’re slightly larger in diameter than English threaded (36mm vs 34.8mm), fit to a 70mm wide shell, and lack the left hand thread on the drive side—it’s a right hand thread.

Colnago and some other brands use Italian threaded on select models, with some brands even sporting French threaded models.

Eccentric Bottom Bracket (EBB)

A standard, non-eccentric BB is fixed; the bearings, and thus the crank, rotate concentrically around the spindle’s center-point—think of a top spinning in the one position.

In contrast, an EBB consists of an adjustable shell that can be rotated around the shell’s center-point, but at a fixed degree of offset—think of the moon orbiting the earth.

An EBB on an MTB is for adjusting crank height.

Rotating the EBB moves the crank spindle both horizontally and vertically; the vertical travel is also height adjustment.

Most road bike users are looking to the horizontal adjustment as a means of loosening and tightening the chain.

And those riders mainly ride fixed gear bikes.

Now, a single speed or fixie is not, categorically, a ‘road bike’ per se. But since 999/1000 fixies live on the roads around towns everywhere, we’ll include it as such … and briefly mention how an EBB is a great choice for a fixie.

But not just any EBB: First’s P237SA is unique in the way it is easily adjusted with a 3mm Allen wrench.

Other EBBs are used as the road bike bottom bracket of choice for tandem bikes, or certain classes of hire bikes.

This type of EBB fits into a non-threaded 54.5mm ID shell (68mm width…standard road bike). Turning the Allen bolts presses two brackets against the BB to hold it in place; a threaded bottom bracket then installs into it.

EBBs such as this model press into a 46mm shell. Tightening the bolts presses the EBB into the shell. Then you install the crank as normal.

Legions of cyclists don’t have problems with press fit BBs. But for every rider that doesn’t rue the day bike companies decided that threadless (press fit) was the way to enlightenment, there seems to be one who does.

The press fit developmental saga finally ended up leaving cyclists with a generous 46mm ID BB shell (I go into the whole sordid chapter in the next section).

Cutting threads into such a shell gives you a threaded ex-PF30, otherwise known as T47.

PRESS FIT ROAD BIKE BOTTOM BRACKETS

The advent of press fit BBs was inevitable.

Bearings came to be successfully slotted directly into integrated and semi-integrated headsets, why not BB shells? An easy peasy “duh…I wish we’d thought of it” no brainer.

We’ll also have a go at answering the often unasked question — was the shift to PF the perfect example of a solution in search of a problem? — at the end of this section. (Once you abandon threads, manufacturing tolerances become hugely important.

Threaded standards worked fine as long as you used grease on the install, avoided cross-threading, and observed torque tolerances.

An even bigger question, though, is does this reflect the deeper, eternal, need for mega brands to get new kit into the market purely as a marketing tactic (think of the steady increase in cassette cogs from 10…to 11…to 12…)?

Are consumers on the sharp end of a stick thickly coated in cynicism (and some weird anaesthetic)? The muppet-engineer detesting Hambini might well agree.

Cannondale’s early 2000s monumental innovation, which landed in the market around 2006, aimed to stiffen integrated crank spindles and decrease the overall weight of a bike’s bottom bracket .

It’s a simple enough system. Instead of a redundant double movement of installing sealed bearings into the frame (BB shell) inside bearing cups, you eliminate the cups and install bearings directly into the frame.

The sequence is:

Install C-clips
Press-in the sealed bearings
Install dust covers
Install the crank

Why 30mm? Because that’s simply the next size of sealed bearing openly available.

For argument’s sake engineers could have determined that 26mm, 32mm or another size was the right way to go.

But that would mean additional expense of obtaining custom races and steel balls to produce a custom sealed bearing, which would have pushed the cost too high.

Success in manufacturing means finding a balance between innovation and production cost—you need enough margin to at least (at the very least!) cover costs whilst putting delivering the product at an acceptable price to the end user.

Anyway, the 6mm increase in spindle diameter from the standard 24mm to 30mm courtesy of a 6806 30mm sealed bearing achieves the desired effect.

The main problem with BB30 is the fit between precisely manufactured 6806 bearings (the OD) and the particular bottom brackets shell into which the bearings directly install.

Measure a representative sample (ie. large enough) of BB shells from

a range of brands
various models within a brand

and you’ll find a range of variation either side of 42mm.

Sure, you’re never going to nail 42.000mm measured to the micro millimeter.

But the need for a precise fit in BB30 rigs means there’s only micro-fractional leeway, and being a few micro millimeters out can result in movement, friction and noise.

Add to this the wildcard of poor installation procedures, perhaps with the wrong tools, then the likelihood of problems is even higher.

The first thing everyone wants to know is the difference between BB30 and PF30.

It’s a good place to start, since PF30 was created in response to BB30.

Come 2009, there was enough discontent towards BB30 among cyclists for SRAM to offer the solution of placing BB30’s sealed bearings back into cups which you would then press into a threadless shell.

Accommodating the 6806 sealed bearing meant increasing the internal diameter of the BB shell by 4mm, compared to BB30, to 46mm.

And that has, arguably, led to the ray of sunshine (ok…ok…depending on your perspective) known as T47 which is, basically, a threaded PF30 (46mm + 1). But, I digress.

PF30 requires specialist tools for installing and removing the cups without damage as illustrated in the video. To reduce the need for a range of tools or a specialist tool set such as the one demonstrated in the video, a self-installing/self-extracting model is an option.

Both the tech and the technique are simple (of course…it’s threaded!). One half of the internal sleeve threads into the other, loosened and tightened by one brand-specific (you won’t find it on Amazon) tool.

Brand-Specific PF Road Bike Bottom Brackets

An important (lamentable?) aspect of the press fit revolution is the proliferation of standards.

Once the PF genie escaped the bottle, most of the big brands came out with their own interpretation of a press fit road bike bottom bracket; and the trend has only recently reversed.

The marketing gambit is to secure or increase market share in the high-end market by coming up with a unique design that has obvious technical advantages.

Does creating a walled garden in this high-end micro-niche result an adequate financial return? Or is it better to go with an open standard and rely on different tactics to increase brand appeal?

The answers to these questions are at the heart of what has been a bewildering increase in high-tech kit, a cross-section of which I review here.

The game was afoot with Cannondale’s 2006 market release of BB30 as an open standard—the following year Trek released the BB90/95 standard countering BB30’s 30mm spindle with a conventional 24mm spindle.

’90’ referred to the 90mm width of the BB shell, not the length of the spindle; the BB shell’s ID is 37mm.

But this was not simply about tit-for-tat with a major competitor.

The adoption of carbon frames for high-end bikes was hotting up mid-2000s, and a key selling point was ‘stiffness’. The stiffer a frame, the better.

Increasing the shell width from the standard road bike spec of 68mm to 90mm adds 11mm of support around the shell on each side.

A frame maker can massively reinforce and thus stiffen the 3-way intersection of the down tube, seat tube, and chain stays to maximally resist pedaling torsional forces.

Given the non-standard dimensions, you need a proprietary road bike bottom bracket to fit—enter BB90 (95 for MTB).

Trek has abandoned BB90 on Domane, now going with a threaded T47 BB which eliminates press fit woes by returning to a standard as T47 is adopted by more brands as we head deeper into the 2020s.

Cannondale: BB30A & BB30-83 Ai

Along with introducing press fit into cycling tech with BB30 as an open standard, Cannondale have also designed their own proprietary variations: BB30A & BB30-83 Ai

‘A’ means asymmetric . The BB shell housing this assembly is 5mm wider than BB30 on the drive side which allows for wider spaced bearings the objective being enhanced spindle support. BB30-83 A requires a BB shell width of 83mm.

And brands issuing new PF designs have made asymmetry central to their quest for a unique selling point.

Cervelo – BBright

In 2010, the year after SRAM introduced PF30, Cervelo introduced their version.

The USP is the asymmetry between the drive and non-drive side.

Cervelo added 11mm added to the non-drive side. This allows a larger, stiffer down tube and seat tube (cf. Trek BB90) and wider of the rear triangle which also increases frame stiffness. The asymmetry ensures fixed clearance between crank, chain rings, and chain stay.

FSA BB386/392 Evo

Five years into the press fit experiment that was polarizing cyclists into those that loved PF and those that hated it, FSA called ‘time’ and initiated the first effort to re-unify standards in 2011 ( SRAM’s DUB being one of the most recent examples).

A variation on PF30, the idea is to accommodate both BB30 and BB86 (using adapters)

Colnago ThreadFit

Colnago’s C60 ThreadFit 82.5 is a sleeve that can take any BB86 (86.5mm to be exact).

The updated C64 82.8 got rid of the sleeve, opting for bonding a threaded alloy insert into the (carbon) frame. Which makes it a threaded system tapping into the still emerging zeitgeist that produced T47: threaded is probably best!

Specialized OSBB

Specialized’s Oversized Bottom Bracket is a variation on PF30: it sports a 68mm wide shell with a 46mm ID.

Final Thoughts on Press Fit

PF is a good solution for the majority of cyclists who use it.

Many experience no problems at all; many, however, put up with constant problems, with a significant group convinced that abandoning threads was a very bad idea.

PF systems promised weight savings and greater efficiency, which they delivered at a meaningful level for the top-tier of pro-peloton cyclists.

If you’re an average cyclist, of course, dropping a kilogram or two—and most of us have many kgs to spare than one or two—has the same effect.

Even the weight loss from dehydration during a ride greatly exceeds the weight efficiency (where weight is really saved or course…) of PF over threaded.

So were the marginal gains worth the cost? Probably not. But, then, for the true fan of cutting edge bike kit, it really doesn’t matter.

As I write, there are some signs of a move back to threaded road bike bottom brackets.

I say “some” signs, since the big brands continue to produce updated models fitted with their proprietary press fit BB systems.

The question that seems to be growing in relevance daily, however, is could it be possible that the mass move to mid-drive e-bikes will eliminate bottom brackets completely (discounting from hub drives)?

THE E ROAD BIKE BOTTOM BRACKET REVOLUTION

The summer of 2016 witnessed the transformation of e-bikes (when top-tier European mountain bikers began riding eMTBs and gave them the stamp of approval) from a small, specialized class of bikes into the key driver of the bike industry from 2020.

Although the Covid-19 pandemic helped with momentum, the die were cast several years prior to the e-bike demand-generating disruptions of 2020-2021.

We will likely look back upon 2020 as maybe not heralding the end of the road bike bottom bracket, but certainly the beginning of the marginalization of what has been a core component of bikes since the Safety Rover revolutionized cycling in the mid 1880s.

Conventional bottom brackets (probably mostly cartridge square taper) will live on for the small group of consumers using conversion kits as a cheap means of creating an e-bike from an old steed.

Otherwise, the increasing number of brands offering mid-drives with integrated and automated shifting will dominate with ne’er a mention of a “bottom bracket”.

The road bike bottom bracket was unchanged for decades up until the adoption of sealed bearings.

The introduction of press fit resulted in brands producing a wide range of proprietary designs and open standards which remain in the market, in one form or another.

As the new category of mid-drive e road bikes continues to rapidly expand, many erstwhile road cyclists will make the switch, thus reducing the demand for conventional bottom brackets.

The road bike bottom bracket will be around forever. But the days of runaway innovation are gone and we’ll likely see a reversion to basic designs as dwindling demand makes keeping the more funky PF BBs in stock unviable.

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To The Point: Understanding Bottom Brackets

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Crankset Standards

Finding the correct bottom bracket for your frame can be challenging. First identify your frame's Bottom Bracket Standard. Then use the chart below to help identify key crankset dimensions needed to select the correct bottom bracket for your frame. Scroll to bottom of page for photos of each crank type.

24mm Spindle Crank (Shimano HollowTech II, etc.)

22mm/24mm Spindle Cranks (SRAM / Truvativ GXP)

29mm Spindle Cranks

30mm Spindle Cranks

Spindle Lengths

When measuring your spindle length for use with Wheels Mfg bottom brackets, measure overall spindle length from the inner face of one crank arm to the end of the spindle. Remove all crank spacers and wave washer if present. If crank has a pre-load adjuster, measure from the face of the adjuster to the end of the spindle.

24mm Spindle Length

22mm/24mm Spindle Length

29mm & 30mm Spindle Length

Most adjusters found on 29mm & 30mm dia spindles can be removed to gain additional overall spindle length. In some applications it may be necessary to remove the adjuster.

Bearing Landing

When determining whether a crank will work with a particular bottom bracket, it is also important to check the bearing landing surface on the crank spindle. Most crank spindles are machined so that bearing landings (22mm, 24mm, 29mm or 30mm diameter) are wide enough and spaced far enough apart to work within a limited range of bottom bracket widths. When attempting to use a much wider crank spindle than your bottom bracket width, make sure that the bottom bracket bearings fall within the bearing landings on your crank.

Shimano HollowTech II

Spindle Diameter

24x37 (Drive) 22x37 (Non-Drive)

Current Shimnao crank specification. Spindle length varies depending on type of crank (road, Mountain, Triple, etc.).  Two-piece system. Crank spindle is pressed into the drive side crank arm.

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The trains and stations of the Moscow Metro

2 Comments · Posted by Alex Smirnov in Cities , Travel , Video

The Moscow Metro is the third most intensive subway system in the world after Tokyo and Seoul subways. The first line was opened on May 15, 1935. Since 1955, the metro has the name of V.I. Lenin.

The system consists of 12 lines with a total length of 305.7 km. Forty four stations are recognized cultural heritage. The largest passenger traffic is in rush hours from 8:00 to 9:00 and from 18:00 to 19:00.

Cellular communication is available on most of the stations of the Moscow Metro. In March 2012, a free Wi-Fi appeared in the Circle Line train. The Moscow Metro is open to passengers from 5:20 to 01:00. The average interval between trains is 2.5 minutes.

The fare is paid by using contactless tickets and contactless smart cards, the passes to the stations are controlled by automatic turnstiles. Ticket offices and ticket vending machines can be found in station vestibules.

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IMAGES

Bottom Bracket Standards and Terminology
CeramicSpeed BB90 Trek Shimano Coated 並行輸入品
Normas y terminología del pedalier
CeramicSpeed BB90 Trek Shimano
Pedalare Verso il Cielo: Test Bike: BB90 (Trek)/ BBRight (Cervèlo)
CeramicSpeed BB90 Trek Shimano

VIDEO

Benchmade Saddle Mountain Skinner
Нож Benchmade Mini Freek, CPM-S90V, Carbon Fiber
SUGINO BB FOR TREK BIKES
Pressfit
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Велоновости 24.09.23. Масштабная отзывная кампания Shimano, Новый Pinarello с Х-образными перьями

COMMENTS

Trek BB90 and 30mm spindle cranks
Firstly the bearings you need are 6706. 30mm ID, 37mm OD, 4mm width. You use two on each side next to each other to make a bearing 30mm ID, 37mm OD, 8mm width. BB90/95 was originally designed around a bearing 7mm wide. So your new arrangement adds 1mm of width to each side.
Trek Integrated Shimano BB90/BB95 Steel Bottom Bracket Kit
Trek Integrated Shimano BB90/BB95 Steel Bottom Bracket Kit. $42.00. Model 524555. Retailer prices may vary. Proprietary replacement bottom bracket for the Trek family of bikes. Compare. Color / Grey. Select a color. Shell width x axle length.
BB90 Bottom Brackets Explained
The other is spindle diameter—the part of the bottom bracket that your pedal crank arms attach to. ... (used on Shimano cranksets) and 30mm (used on SRAM cranksets). Bottom brackets are also available in different configurations and materials. ... There is really only one bike manufacturer that uses BB90 and that's Trek Bikes. BB90 is their ...
Bottom Bracket Tech Breakdown
To Note: BB90 is a Trek only standard that does not use external cups. The bearings (which are spec'ed to fit a 24mm external BB spindle)press directly into the carbon frame similar to a BB30 system except for the fact that a BB90 is "90"mm wide and a BB30 bottom bracket is 68mm wide for road and 73mm for MTB.
Bottom Bracket Basics: Cyclists' Guide to Standards
Bearing adapters are made to fit different crank spindle diameters, such as 22/24mm, 24mm, 28.99mm, and 30mm." Trek released the BB90 and BB95 as its standards in 2007. The bearings are pressed ...
The Ultimate Guide To Bottom Bracket (Types, Standards, And More)
13. Trek BB90 and Trek BB95. ... Both standards use a 30mm spindle and oversized bearings to reduce weight and increase stiffness. However, the BB30A has a larger shell inner diameter of 42mm compared to the standard BB30's 68mm. This allows for a wider stance of the frame's down tube and seat tube, improving stiffness and handling.
Which BB? A beginner's guide to Bottom Brackets
These bottom brackets (the BB90/95 from Trek and the PF86/92 used by Giant, Scott and others) use the same bearings and locations as the threaded design. The difference is the bearings are pressed into cups mounted inside the frame. ... BB90 and PF86, but with the 30mm spindle of the BB30 and PF30. As they use the same size and design elements ...
Trek Integrated Shimano BB90/BB95 Steel Bottom Bracket Kit
Model 524555. Retailer prices may vary. Proprietary replacement bottom bracket for the Trek family of bikes. Compare. Color / Grey. Select a color. Shell width x axle length. BB90/BB95 x No axle. Order now or check below to see what's in stock at your local shop.
Ceramic Trek Bottom Brackets
Find ceramic Trek bottom brackets for every Trek road, mountain, cyclocross bike including BB86 BB92 BB90 bottom brackets. ... Sram GXP, or any other 30mm or 24mm diameter crank spindle. See The Collection. Trek Road Bike Bottom Brackets Trek has used the BB90 bottom bracket standard for years in their Madone and Domane road bikes. BB90 is a ...
BBInfinite Trek BB90 Bottom Bracket Solutions
Don't listen to the Trek BB90 haters. BB90 is the absolute lightest and stiffest bottom bracket system available, and when you do things the BBInfinite way, BB90 becomes the quietest and highest performance bottom bracket system as well. ... Only modules designed for a 30mm spindle require a bushing due to variances in 30mm crank set design and ...
Your Definitive Road Bike Bottom Bracket Guide (Incl E-bikes)
Trek BB90. The game was afoot with Cannondale's 2006 market release of BB30 as an open standard—the following year Trek released the BB90/95 standard countering BB30's 30mm spindle with a conventional 24mm spindle. '90' referred to the 90mm width of the BB shell, not the length of the spindle; the BB shell's ID is 37mm.
To The Point: Understanding Bottom Brackets
The BB30 and Trek's proprietary BB90 system are also used, but not as extensively as the other styles. ... Both standards are designed to use a crank arm spindle with a 30mm diameter (hence the ...
Three Common Bottom Bracket Misconceptions
BB86/92, BB90/95 & PF92. BB86/92 and Trek's BB90/95 are often misidentified. While the "30" in BB30/PF30 references the inside diameter of the used, the numbers in BB86/92 and BB90/95 refer to the width of the frame's bottom bracket shell. The BB86/92 bottom bracket system uses a bearing pressed into a cup, which is then pressed into the frame.
Trek Integrated BB90/95 FSA Bearing Kit
Trek Integrated BB90 Shimano V2 Oversized Bottom Bracket Bearing. $19.99. 1 of 21. Enhance your cycling experience with Trek BB90/BB95 FSA Alloy Bottom Bracket Kit.
bottom bracket
DUB (28.99mm spindle) falls into the latter category. GXP spindles (24mm, tapered to 22mm on one side) fall into the former. Almost all press fit bottom bracket shells can take cranks with 30mm or similar spindles. Trek's BB90 bottom bracket standard appears to be an exception.
Crankset standards chart
Two-piece system. Crank spindle is pressed into the drive side crank arm. Uses wave washer on drive side of crankset to take up any play in crank. SRAM DUB: 29mm; 29x42; SRAM introduced the DUB cranks in 2018. 29mm diameter spindles. Meant to be used across all BB standards. BB30: 30mm; 6806 (Drive) 6806 (Non-Drive) 30mm spindle diameter cranks.
Ceramic Trek Bottom Brackets
Choose from options below to install any Shimano, Sram GXP, or any other 30mm or 24mm diameter crank spindle. See The Collection. ... Trek has used the BB90 bottom bracket standard for years in their Madone and Domane road bikes. BB90 is a standard used on Trek carbon road bikes only. Bearings drop directly into the frame shell, which is 90.5mm ...
The trains and stations of the Moscow Metro · Russia Travel Blog
The Moscow Metro is the third most intensive subway system in the world after Tokyo and Seoul subways. The first line was opened on May 15, 1935.
STELS, OOO
Find company research, competitor information, contact details & financial data for STELS, OOO of Elektrostal, Moscow region. Get the latest business insights from Dun & Bradstreet.
Trek Integrated Campagnolo BB90/BB95 Steel Bottom Bracket Kit
More options. Enhance your cycling experience with Trek Integrated Campagnolo BB90/BB95 Steel Bottom Bracket Kit. Shop now!
9th radio centre of Moscow, Elektrostal
The 9th radio centre of Moscow was a high power shortwave and medium wave broadcasting facility at Elektrostal near Moscow.Its broadcasting frequency was 873 kHz with a transmission power of up to 1200 kilowatts. It was also used as radio jammer of "unwanted" stations.
Wheels Manufacturing BB30-KIT Bottom Bracket Kit
Top-notch bottom bracket. This BB30 service kits is a direct replacement for OEM BB30 and BB30A systems and has everything to keep you spinning smoothly. Including two Enduro 6806 ABEC-3 sealed bearings and two retaining clips, this kit is a great choice for any BB30/BB30A equipped bike.
SORSHA RUS LTD. Company Profile
Find company research, competitor information, contact details & financial data for SORSHA RUS LTD. of Elektrostal, Moscow region. Get the latest business insights from Dun & Bradstreet.

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BB90 Bottom Bracket problems

BB90 bottom bracket replacement

What’s the future of BB90 bottom brackets?

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Bottom Bracket Tech Breakdown

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Bottom Bracket Basics: Cyclists’ Guide to Standards

Threaded Bottom Bracket Standards

Press-Fit Standards

Bottom Bracket Compatibility

Bottom Bracket Basics: Cyclists' Guide to Standards

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The Ultimate Guide to Bottom Bracket

Table of Contents

Threaded Bottom Bracket

Press Fit Bottom Bracket

Bottom Bracket Standard

ISO Threaded Internal Bottom Bracket

ISO Threaded External Bottom Bracket

Differences between ISO Threaded Internal and External Bottom Brackets

2. Italian Bottom Bracket

Differences Between the Italian Bottom Bracket and BSA Threaded Bottom Bracket

4. Colnago ThreadFit82.5

5. Truvativ ISIS Overdrive

7. Chater-Lea

8. Whitworth

9. O.P.C. Ashtabula

10. O.P.C. Fauber

11. Raleigh

12. BB86 and BB92

13. Trek BB90 and Trek BB95

14. Look BB95

15. Wilier BB94

16. Specialized Alloy OSBB

17. Specialized Carbon OSBB

Specialized Carbon OSBB vs Alloy OSBB: Which is better for your bike?

BB30 vs Specialized OSBB: Which is Better?

19. Cannondale BB30A and BB30-83 Ai

Differences between PF30 and BB30

21. BBRight (Press-Fit)

22. BBRight (Direct-Fit)

Difference between Press-Fit and Direct-Fit

23. BB386EVO

24. BB392EVO

25. Spanish

Why There Are so Many Bottom Bracket Standards

Bottom Bracket Installation

Maintaining a Bottom Bracket

When to Replace a Bottom Bracket

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BBInfinite Trek BB90 Bottom Bracket Solutions

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Also in BBInfinite exists to elevate the bottom bracket to the high-performance, low-maintenance, reliable component it is meant to be. Rid yourself of press fit bottom bracket creaks and pops. BBInfinite is silent performance.

BBInfinite Tech Tip: Chain in the way?

Hydraulic Disc Brake Bleeding Done Right (Shimano)

Press Fit 30 Perfection

Bottom Bracket Selection Guide

Your Definitive Road Bike Bottom Bracket Guide (Incl E-bikes)

The THREADED ROAD BIKE BOTTOM BRACKET

Eccentric Bottom Bracket (EBB)

PRESS FIT ROAD BIKE BOTTOM BRACKETS

Brand-Specific PF Road Bike Bottom Brackets

Cannondale: BB30A & BB30-83 Ai

Cervelo – BBright

FSA BB386/392 Evo

Colnago ThreadFit

Specialized OSBB

Final Thoughts on Press Fit

THE E ROAD BIKE BOTTOM BRACKET REVOLUTION

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To The Point: Understanding Bottom Brackets

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