Bicycle Mechanics - question about bottom bracket

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ThomasA
08-21-08, 11:21 AM
As long as the bottom bracket has the right threads, the width is depending on the crankset, not the frame, correct? I'm changing cranksets and it says to use a 118.5mm. I just want to make sure it'll work with my frame. Thanks
-Thomas

Bill Kapaun
08-21-08, 12:57 PM
Probably, if you have the "standard" English threaded shell.

http://sheldonbrown.com/harris/bottombrackets.html#sizes
bing4sons
08-22-08, 08:19 AM
The Shimano 118.5 is for a triple. I just put one on my Trek. Mine was English thread, ie. 68mm.

HillRider
08-22-08, 08:49 AM
As long as the bottom bracket has the right threads, the width is depending on the crankset, not the frame, correct? I'm changing cranksets and it says to use a 118.5mm. I just want to make sure it'll work with my frame. Thanks
-Thomas
Not completely. "English" threaded bottom brackets come in two shell widths, 68 mm (road) and 73 mm (some MTB), so the bottom bracket has to match the shell width too.

A more correct way to state it is that the crankset defines the spindle length.