new bottom bracket
10-24-09, 04:34 PM
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new bottom bracket
I need to buy a new bottom bracket becuase my current one is rusted and the the thread is wearing away. The current sized bracket i have is a 68mmX121.5. Is is necessary that i get another which is EXACTLY 121.5? will too long or too short throw off my chain line? I am removing my current 3 ring crankset and replacing it with a single ring.
Thanks for the help.
Thanks for the help.
10-24-09, 08:48 PM
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Old fart
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If you're replacing a triple ring with a single ring you will want a much shorter spindle. Exactly how much shorter depends on the spindle, the crank arm, and the frame.
10-24-09, 08:57 PM
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The crankset determines the length of the spindle. It's most likely that the new crankset will require a shorter spindle (as already mentioned).
10-24-09, 10:11 PM
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Thanks, I eventually pieced all that info together, but no one said it as concisely.
basically, I need to chose a crank before i pick a BB
basically, I need to chose a crank before i pick a BB
