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Old 09-04-11, 03:00 PM   #1
mauricio2
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derailleur bounce

Hello, I've encountered a small obstacle recently. I purchased new square taper cranks/chainring, and after installing on the bike, and testing them out, I began experiencing a "bounce" from my rear derailleaur, after every four or five pedal revolutions. I purchased a similar set of new st cranks/chainring for another bike, and the same thing started happening. Both bikes rode fine before this. It's not alignment, nor stiff links. All suggestions welcome. Thanks.

Last edited by mauricio2; 09-04-11 at 03:08 PM. Reason: new info
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Old 09-04-11, 03:06 PM   #2
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The frequency of the problem hints at a chain problem, ie. once per loop of the chain.

Check your chain for a stiff link as follows. Shift to a neutral gear where it backpedals smoothly, ie. outer and 2nd or third sprocket. push the RD tension pulley forward so the lower loop sags a few inches, and back pedal slowly while looking looking for a link that doesn't straighten immediately into the curve of the sagging lower loop.
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Old 09-04-11, 04:05 PM   #3
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Quote:
Originally Posted by FBinNY View Post
The frequency of the problem hints at a chain problem, ie. once per loop of the chain.

Check your chain for a stiff link as follows. Shift to a neutral gear where it backpedals smoothly, ie. outer and 2nd or third sprocket. push the RD tension pulley forward so the lower loop sags a few inches, and back pedal slowly while looking looking for a link that doesn't straighten immediately into the curve of the sagging lower loop.
^^^
This. Stuck link somewhere.
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Old 09-04-11, 07:20 PM   #4
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Case closed.
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