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Crank/BB flex(4 posts)

Crank/BB flexridewt
Dec 29, 2003 2:36 PM
I've got a Lemond aluminum with Campy Chorus crank and BB. I've noticed that I get a bit of flex of some sort that can cause the large ring to move back and forth and sometimes rub on the front der. In other words, the large ring does not track perfectly. The deflection is consistent with whatever side I'm applying pressure. I suppose some deflection is normal but does this seem normal? The crank bolts, and chainring bolts are tight and the crankarms don't appear to have any "play" in them. By the way, this only appears to happen when I'm applying some significant pressure.
re: Crank/BB flexdivve
Dec 29, 2003 4:09 PM
For the most part it's the frame.
It's the frame flexingKerry Irons
Dec 29, 2003 4:29 PM
You say that the chain ring is rubbing on the derailleur, but I assume that it's the chain you're talking about. If the CR rubs the derailleur, you've got things set up seriously wrong. Chain rub when under hard pedaling is not uncommon, but it is the frame flexing, not the crankset (99 times out of 100).
It's the frame flexingridewt
Dec 30, 2003 6:48 AM
Thanks for the replies. Yes, you're right, it is the chain rubbing; I misspoke there. I'm not a huge guy (maybe for the bike world - 6'3", 182 pounds) but I guess the frame is flexing.