Bicycle Mechanics - BB Size / Compatibility

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fwc

06-26-06, 04:47 PM

I currently have a Truvativ Elita SL crank and Truvativ ISIS GigaPipe SL Bottom Bracket (68/108) and would like to swap in an Ultegra 6500 crank and Ultegra 6500 Bottom Bracket. I see the Ultegra 6500 BB listed in 68/109.5. Bike is an 05 Cannondale R700. Will this size work, any issues I am missing, will this swap work anyway? Opinions?

Retro Grouch

06-26-06, 04:52 PM

Yup. Looks to me like a straight bolt-up. This is a good place to use a torque wrench particularly on an aluminum frame.

HillRider

06-26-06, 08:45 PM

The bb length is specified by the crank maker and the fact that the Shimano and Truvative bb's are similar in length is just a coincidence. Use the maker's specified bb.