Bicycle Mechanics - Bottom Bracket Compatability

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Lexi01
10-28-12, 09:11 PM
Ola.

I just got a new FS MTB and it came with BB92 and SRAM S-1000 GXP cranks.

I want to swap the cranks for XT (BB30).

What do I need to do (or be aware of) to do this?

Ta.

Lexi01
10-29-12, 04:18 PM
Must be a hard question...
cny-bikeman
10-29-12, 04:26 PM
I have no experienc at all with this, but Google does: "bb92 to bb30". First two links have discussion of both possibility and practicality.

Lexi01
10-29-12, 04:44 PM
Ta. I did see those two discussions but didn't read far enough down...

thm clavicula adapter BB92 to BB30 appears to be the answer.
Lexi01
10-29-12, 04:57 PM
Actually - it seems Shimano now make their own BB for BB92 frames...

http://www.competitivecyclist.com/product-components/2013-shimano--bb92-bottom-bracket-10061.19.1.html

It says this BB fits BB92 frames and allows for hollowtech cranks.

Just an FYI for those searching in future.
davidad
10-29-12, 05:07 PM
Thank goodness for all of this new and improved s.....tuff. :troll:
well biked
10-29-12, 07:40 PM
I want to swap the cranks for XT (BB30).



I know you seem to have this figured out already, but I thought I'd throw a little info into the mix........There's no such thing as a BB30 Shimano XT crankset. Shimano doesn't make cranks with a 30mm diameter spindle, and to truly be a BB30 crankset, the spindle will be 30mm in diameter. If you had a BB30 frame with BB30 bottom bracket bearings, and you wanted to use a Shimano Hollowtech II crankset, such as current XT, you would need to use adapters to shim the Shimano 24mm crank spindle into the BB30 bearings (the adapters work great, btw).

BB92 is another story, it's a system that's intended for cranks with 24mm spindles, so the XT crankset with the Shimano bearings you intend to use should be no problem.