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Odd problem

Old 03-20-08, 08:19 PM
  #1  
Mash Master
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Odd problem

For some reason lately my bike has started to lose the chain off the front gear. It only seems to have when I'm in the big gear in front and the little gear in back. When I pedal with normal cadence there is no problem, but when I try to really push in this gear the chain comes off the big ring. What would cause this? Should I bring my front deraileur in a smidge?
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Old 03-20-08, 08:40 PM
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kramnnim
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So...the chain falls off away from the middle ring, to your right?
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Old 03-20-08, 08:43 PM
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It is a compact double. The chain falls off the big ring to the right.
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Old 03-20-08, 08:51 PM
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Bill Kapaun
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Maybe a "slightly" stiff chain link?
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Old 03-20-08, 08:54 PM
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you wouldn't happen to have a truvativ elita crankset with a shimano ten-speed rear mech, would you?
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Old 03-20-08, 09:23 PM
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At the large chainring, small cog combination, adjust the FD limiter such that the FD is about 2mm away from the chain.

I once had a chainring that would drop off the large chainring, and it turns out it was due to a bent tooth on the large chainring.
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Old 03-20-08, 09:31 PM
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I'm guessing that you're flexing the cranks or bottom bracket with the force. And this flexing is moving the chain rings enough to drop the chain. Moving the FD cage in a little so it acts a little like a chain guide should avoid this issue. And it wouldn't hurt to check that the BB rings and the crank bolts are tight
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Old 03-20-08, 09:31 PM
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It is an FSA carbon crank. I have a new chain in the mail already so maybe I'll swap out the chain when it comes. My chain gauge shows 75%.

I'll try cleaning the chain as well as adjusting the limit screw.
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Old 03-20-08, 10:07 PM
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Originally Posted by Mash Master View Post
It is an FSA carbon crank. I have a new chain in the mail already so maybe I'll swap out the chain when it comes. My chain gauge shows 75%.

I'll try cleaning the chain as well as adjusting the limit screw.
That should do it. Also make sure the alignment of the FD is good.
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