First, you need to see if you need a "power drive" or a JIS bottom bracket (splined interface or square taper respectively). JIS bottom brackets are bog cheap. Being that your bike is non-standard, if you need square taper, I would either use the expertise of an old-school mechanic (this BB design is, like, 20 years behind the state of the art) to give you advice, or experiment a little. Start at 110 maybe, but realize you might need to change. Also, you need to determine if the bottom bracket needs to be symmetrical or have an offset. Good luck!
If it's "power drive" you need, then just go with what FSA recommends. Also, you might get better help in the "mechanics" section of the bikeforums, since this tech is so out of date.
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Cat 2 Track, Cat 3 Road.
"If you’re new enough [to racing] that you would ask such question, then i would hazard a guess that if you just made up a workout that sounded hard to do, and did it, you’d probably get faster." --
the tiniest sprinter
Last edited by Brian Ratliff; 11-04-13 at 11:23 AM.
Reason: more confusing because the crank come in two flavors of BB interface.