Bicycle Mechanics - Will this crank work on my bike? BB30 or GXP?

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.




Kind of Blued
04-26-11, 01:44 AM
http://www.specialized.com/us/en/bc/SBCEqProduct.jsp?spid=56855

It says BB30-"COMPATIBLE", but will it still work with a GXP BB?

The bike in question is a Roubaix SL2 which currently has a Truvativ Powerspline BB and SRAM S150 crankset.

I really appreciate any convincing insight here. Thanks.


commo_soulja
04-26-11, 02:07 AM
That's a good question that I'd like to know too. With all the different BB standards, things get confusing. I'm still using square taper and ISIS BBs and cranks.

CCrew
04-26-11, 03:58 AM
"Fits Specialized frames with oversized bottom bracket shell"

I'm betting not..


jimc101
04-26-11, 05:04 AM
That's a good question that I'd like to know too. With all the different BB standards, things get confusing. I'm still using square taper and ISIS BBs and cranks.

With so many different standards, it is simplest to always go for the same standard that you currently have, rather than attempting to get adaptors, just get another crank which will worth with a BB30. All this info will be on the manufactuers websites, just match the part number with what you are looking to do with it.

Kind of Blued
04-26-11, 03:07 PM
"Fits Specialized frames with oversized bottom bracket shell"

I'm betting not..

Even the SL3 bikes don't have anything about an "oversized BB shell" on the Specialized website. I'm 99% sure I can swap the GXP I just bought for the Powerspline BB, but I think I need to have a "GXP crank".

Question: Is the actual cavity needed for BB30 larger than that for GXP? I've seen adapters that allow a non BB30 crank in a BB30 compatible frame, but not vice versa, which leads me to to believe BB30 is bigger, and the adapters can only make things smaller.

reptilezs
04-26-11, 04:26 PM
powerspline bb means you have a traditional 68mm english bb. that crank is for bb30 and will not work

Lawrence08648
04-26-11, 06:30 PM
powerspline bb means you have a traditional 68mm english bb. that crank is for bb30 and will not work

I agree with Reptilezs, it won't work. This is not a BB30 crank. It's a Powerspline crank and will only work with a Powerspline BB. BB30 cranks only work with BB30 bearings which are outboard, you can see the ring on each side of the outside of the housing. A BB30 crank is held on with 2 bolts, 1 on each side of the crank then the other crank is attached to the axle.

Kind of Blued
04-26-11, 07:10 PM
Ok, so SRAM Red GXP it is. Thanks guys, would have been easier if Specialized had worded things better in the description.