BB30 Bottom Bracket Compatibility
 

So, I've been trying to find the answer to this question, but reading many posts has just got me more confused, along with mixed answers. Here's the question: will a 68 mm bottom bracket shell work with a BB30 bottom bracket (on a road bike)?

No with the info given, bit confused with the question, no mention of what you are actually planning to do.

A 68mm (threaded) shell would fit either an internal i.e. square taper/ISIS/Octalink, or External i.e. HT2/GXP/MegaExo.

BB30's are pressfit, and require the frame to have the shell designed for this.

The frame determines the BB type, which determines the crank type (this should match or be compatible with adapters)

Have a look here for mode info, Park Tool Co. » ParkTool Blog » Bottom Bracket Standards

More info about what you are planning to use would really help with a question like this.

A BB30 bottom bracket does fit in a 68 mm wide shell, but not the common BSA, 68 mm wide, threaded shell. That takes a threaded cup bottom bracket of one type or another. The BB30 bottom bracket is just a pair of cartridge bearings with snap ring retention clips that sit behind them in the shell. The BB30 shell is not threaded as the bearing cartridges are pressed into the shell for a tight fit.

Okay that's what I needed. So it will not fit a threaded shelling. Thank you

I am looking for a new frame to buy that will fit my Ultegra crankset that uses a BB30 bottom bracket. Currently I have a frame that's using a square taper bottom bracket with a triple crankset and I'm just looking to upgrade. I need a smaller frame anyway.

I use this PDF whenever I'm in doubt about bottom brackets: http://problemsolversbike.com/files/..._Reference.pdf

Please note, that you can probably find an adapter, or - more preferably - an adaptor bottom bracket to use your shimano crankset with any kind of bottom bracket standard. The key is to research the bottom bracket options for the specific frame first. Then find the best option for shimano cranks.

Good manufacturers to start with are: praxis works and hawk racing with a wide range of special bottom brackets for shimano cranks.

None of this really makes sense. First of all there is Shimano doesn't make BB30 cranksets so any Ultegra crank you own is not BB30. Secondly buying a frame to based on compatibility with crankest you own is all backwards. If you want a new frame, shop for the best frame and then get a crank. If you find a BB30 frame that you like, there are adapters to let you use non BB30 cranks. If you have an old triple crank why not look into new components? You can get an entire 11 speed 105 group for about $370. But since it seems you need or want a new frame and new cranks?? why don't you shop for a new complete bike?

Yes, there are adapters from the unthreaded BB30 shell to allow use of Shimano cranks.

Buy a bike with a threaded 68 mm bb and the your crank will fit perfect and you will have a better set up all around. A press fit frame bb can use adaptors for shimano cranks but myself as a good wrench give me a standard BSA threaded BB any day of the week over press fits.

Is there any way to tell what kind of bottom bracket the cranks are attached to without removing the crankset? I don't have the tools to do that. I'm sorry that this seems ridiculous but I definitely need a new frame (mine is too large for me). And I don't have a lot of money to buy new equipment. I already have a full ultegra groupset ready to be put on a bike that will fit it. I'm taking the time to look for a frame that is the right size and hopefully that will fit my crankset.

Which Ultegra group? 9 speed, 10 speed, 11 speed?

It's a 10 speed Ultegra group from 2007-8

It is a very rare bottom beacket shell that can not be adapted to an Ultegea crank.

I don't know if we've mentioned it in a while so I'll go for it (for personal reasons).....

Anybody else think it's about time for Shimano to get on board & make some BB30 cranks?

(Even if I didn't have a BB30 bike, I'd still argue, it's long overdue)

Alright.


You probably have an ultegra 6600. It doesn't really matter, because all recent Shimano cranks have a 24mm spindle and that works best with traditional threaded bottom brackets (British or Italian). Can you tell me about your current frame? If it's also from around 2007-2008 it's 90% that it has british threaded bottom bracket. It's quite hard to tell the exact type without removing the crank though.


In general I think the best to go with BSA (british threaded) frames especially that you already have shimano cranks. The problem is that most of the framesets nowadays have some other "standard". In that case make sure you know the BB standard of the frame you buy AND the cost of making your crank work with it. If you only want to make it work you can buy an adapter for just about any modern BB standards. Also you can later upgrade to conversion bottom brackets made especially for your situation. But both of these options will cost you something.




IMHO BB30 is a failed standard. Some of the standards with 30mm spindles are better than others, but I still think that there is no real benefit of moving from 24mm to 30mm spindles. You can buy a conversion BB for every situation now, so it's not a real problem if you know what you're doing. If shimano moved to 30mm, it would break compatibility with all of their modern cranksets and I think it would be a painful move (especially for current users). I'm not saying it won't happen sometime, but I'm gonna be very sad that day.

Sram makes bb30 and gxp versions of their cranks and others like fsa make cranks for different standards so it would be nice for shimano to do the same. There is some benefits in bb30 that the system is lighter and 30mm spindle is stiffer

Before I knew what all the BB30 hubbub was about, I remember wondering why Cannondale went so far on all the equipment on my bike to make everything Ultegra 6800 except for the cranks. But then I thought, "Well, the wheels aren't Ultegra & they could've been so maybe Cannondale wants to keep some diversity in the package." (To their benefit, I'm sure) But, alas, I think the real reason lies in the fact that BB30 is their standard but Shimano don't play that. Sooooooo.....they team up with folks like FSA or (most recently) their Hollowgram/Spidering stuff to answer that call.

Admittedly, I have no problem with it, though the purists would say, "Well, that's not a true Ultegra groupset bike!". (No biggie to me)

As to whether BB30 is a failed standard......well....I could either point you to my own "Another BB30 creak" thread where I was rather enlightened as to how effectively simple and efficient it is (if not misunderstood). And simultaneously shown how derivatives of BB30 seem to come back to BB30. Or just point you to rpenmarker! ;)

Admittedly, Cannondale might have field tested more exhaustively to create the kind of maintenance schedule most folks could simply handle themselves before annoyances become internet talking points, but such is the case. If there's something I could change, it'd be a much more lengthy maintenance interval, but maybe another standard down the road.

(shrug)

^This is your answer. Basically buy whatever frame you like because your Ultegra crank can be used in whatever frame you choose. You may need to use a different bottom bracket than what you currently are running but that is a simple matter of buying the right one for your new frame if necessary. You may be able to use the same bottom bracket you have now if your new frame has the same type of bottom bracket shell as your old frame. The BB shell is the portion of the frame that holds the BB.

I think we are waaay off topic now. I do have a cannondale bike and I use praxis works conversion BB (BB30 standard with 24mm spindle opening) and ultegra cranks. I'm quite happy with this setup. I don't believe in this stiffness nonsense.

You shouldn't throw a 30mm crank under the bus because it only exposes your ignorance about it. You view through your personal lens. There is a guy on here who has broken a DA crank with his weight and power. That guy isn't you or me. A 30mm crank will be both lighter and stiffer than a 24mm crank if designed right. This is based upon moment of inertia and section modulus. A shorter spindle crank like a BB30 will also have greater beam stiffness and again be lighter because the crank spindle is shorter.
All said, I am a big fan of DA cranks. But there is nothing inherently bad about a 30mm spindle...it is directionally correct in fact and why it came into being. It may not be noticeably stiffer for you or for me but a world class sprinter may appreciate it. But it will be lighter and stiffer for everbody.

As to BB30, your choice of Praxis which is a superb BB etc, this is all personal preference. You could easily run a BB30 crank on your bike without regressing it to a heavier and more expensive BSA with a Praxis sleeve. BB30 is fine but only if you can follow basic installation steps and this forum has proven that many if not most can't. But just like loimpact, once they learn, its pretty smooth sailing with BB30, the light gets turned on and generally appreciation for the beauty and simplicity of the design becomes understood.

Thank you for all your help everyone. I'm looking at a frame that is my size and has a 68 mm threaded bb.

This is all correct. Personally I'm now running Shimano on my CAAD10 because the Shimano cranks look better :thumb:

Poppycock!!!

;)

Awesome link. I've downloaded & added to my reference docs library.

Thank you very much for sharing! :thumb: