Chuck Schmidt wrote:
>I think those messengers are retightening their crank
>bolts, a real no-no.
Hello Chuck, Since traditional square-taper cranks will soon be a thing of the past* I think further discussion can be considered to have classic content, and therefore be relevant to this list. Am I reaching? (* what Shimano innovation hasn't Campy copied lately?)
All kidding aside, I have never heard of anyone recommending against retightening crank bolts. In fact, the standard practice is to retighten crank bolts at least once in the first couple hundred miles after installation. I've always applied this to new and used crankarms. I've also noticed that the amount of retightening needed on high-end cranks is far less than on mid-grade cranks. Why do you describe retightening as a "no-no"?
While we're on the subject... Has anyone heard that Campy recommended replacement of the crank bolts every time the crank was reinstalled? I heard this somewhere, but I've never seen anything official. Seems hard to believe, since the bolts just aren't that stressed and failure is very rare (to say the least).
Finally... Any possibility that problems with crankarm fit on the messenger bikes Mike refers to are caused by conditions specific to fixed-gear use? On a freewheeling bike, the spindle-to-crank interface is always loaded in the same direction, on a fixed gear bike, the interface is loaded in alternate directions, under both pedaling and braking. I imaging that a messenger (foolishly, IMHO) riding a fixed gear in city traffic would do a lot more back pedaling than a rider using a fixed gear on the track. Have any experienced track mechanics noticed more problems with BB/arm fit on fixed bikes?
Tom Dalton
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