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Old 04-19-05, 06:42 PM   #1
dee-vee
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When I am in the middle front chain ring and the biggest back ring my chain rubs on the front derailleur on the left side. Also when I am in the smallest front ring and smallest back it rubs in the right side. Do I need to adjust the front or rear derailleur to fix this? I will probably just bring it into the shop and hopefuly they can fix it as part of my "free lifetime tuneups".

Oh also, sometimes when I shift into a new gear and I apply preasure to the pedals the chain seems to jump a link or something because the pedals lurch foward a short distance.

thanks
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Old 04-19-05, 06:53 PM   #2
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Originally Posted by dee-vee
When I am in the middle front chain ring and the biggest back ring my chain rubs on the front derailleur on the left side. Also when I am in the smallest front ring and smallest back it rubs in the right side. Do I need to adjust the front or rear derailleur to fix this? I will probably just bring it into the shop and hopefuly they can fix it as part of my "free lifetime tuneups".

Oh also, sometimes when I shift into a new gear and I apply preasure to the pedals the chain seems to jump a link or something because the pedals lurch foward a short distance.

thanks
Current road triple shifters with the exception of Sora have a trim feature in the shifter to take care of derailer rub. Ideally you should not be using either gear combination you mention, especially the small/small. The shop shoulda showed ya how to use the shifters, and gear combinations,and the owners manual may have instructions.
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Old 04-19-05, 07:21 PM   #3
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The previous answer is correct. On my Felt 80 I had a similar situation and downloaded the adjustment information from the Shimano site. The bottom line is that you should not use the extreme gear configuarations. On my particular bike I was able to adjust it to be able to use all configurations except the largest chainring and the smallest gear on the rear. Not really a big problem, as other gears are readily available. What may happen is that you will stress the shifting mechanisms or even possibly cause the chain to rub against part of your derailluer (sp). Hope this helps.
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Old 04-19-05, 07:27 PM   #4
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My rear derailleur is a Sora. It starts to rub even if im in the 2nd or 3rd largest ring.
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Old 04-19-05, 07:53 PM   #5
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It depends on the angle in which the gears puts the chain. The adjustment screws for the limit stops will help to allow the derailer move farther left or right away from the chain. Also, the greater the chain angle, the more side to side tension on the chain increases, causing chain and sprocket wear. Proper adjustment and gear choice will fix it!

If it ain't broke, you're not trying hard enough! - Red Green

Hope I made sense??
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Old 04-19-05, 07:59 PM   #6
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It depends on the angle in which the gears puts the chain. The adjustment screws for the limit stops will help to allow the derailer move farther left or right away from the chain.
The limit screws are not for adjusting out derailer rub, other than adjusting for the correct chain to inner cage clearance when in the small/small when doing the initial setup.
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Old 04-19-05, 08:03 PM   #7
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Originally Posted by dee-vee
My rear derailleur is a Sora. It starts to rub even if im in the 2nd or 3rd largest ring.
I duno what the RD has to do with FD chain rub.
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