poupou

I have 2 raceface isis cranksets and 1 isis truvativ bb. The bb is 113mm but is too long for the cranks - I can't get my 44. Is a 108mm bb the logoical way to go; are there other lengths available?

Thanks
poupou

HillRider

A shorter bb will improve the situation as long as the crank doesn't get so close to the frame that a chainring hits the chainstay.

Have you tried to adjust the inner limit screw on the front derailleur to let the derailleur move in further? Maybe that's all you need.

TallRider

If the FD limit screw is your problem, you should also think about chainline. When the chain is in the middle ring of the chainring (since you mentioned a 44, I'm assuming you have a triple), what rear cog are you lined up with? If the middle chainring is lined up straight with the middle cog on the rear, then you don't want a shorter bottom bracket if you can get away with it.
I've half a thought that you should actually be running a 118mm bottom bracket - my understanding of the ISIS standard is that road doubles are supposed to take a 108, road triples a 113, and mountain triples (to go with a 135mm-spaced rear hub; road rear hubs are 130mm) should be a 118.

AnthonyG

Assuming you have double cranks then a 108mm BB would be better but a 113 mm one should still work, just not with such a good chainline. Sounds like your front deralier needs adjustment.

Regards, Anthony