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Help me help me! Bent derailleur?

Old 05-03-11, 07:28 AM
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llmercll
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Help me help me! Bent derailleur?

Hello, I recently got an older Peugeot bike out of storage in the hopes I could repair it and ride it on a little bit, or get it set up for my brother.

The bike is having a serious issue with gears. It seems like whenever I ride, even without shifting, the chain little by little keeps going into the smaller "gear". So if I manually put the chain on the largest tooth, it will automatically go to the smallest over the course of maybe 25 peddle rotations.

Eventually it gets jammed because it runs out of gears, and the rear wheel completely locks up.

Any idea what the issue is and how to fix it?

thanks!
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Old 05-03-11, 07:35 AM
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You have two different problems.

First, based on your description I assume you have friction (no clicks) shifting. If so you'll find a wingnut or screw where the lever is mounted. Tighten that slightly so the lever holds against the derailleur's return spring and that will solve the auto-shift issue.

The second is to set the limit screws on the derailleur itself so it cannot go beyond the last sprocket on either end. Search "adjusting rear derailleur" and you'll find a bunch of tutorials. Most are for more modern derailleurs, but the limit screw adjustment is the same on yours.
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Old 05-04-11, 04:19 AM
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llmercll
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Thanks for the reply =)

I believe the shifters are ok. They are handlebar shifts and click when I twist them. They seem to change gears too, but I've noticed that the gear they go in are not the correct gear. For instance I'll want to be in 3-7 but I'll really be in 2-5. I lifted the bike up and ran the peddles with my hands and it was working fine, though. No more auto shifting. Although if I turn the peddles backwards, the chain gets messed up =/

I also have an issue wherer the rear tube keeps "seeping" out of the rim/tire.

I will take some pictures today and upload them, maybe that will help more than my unexperienced description =p

And it seems like the one hex key I need is the one I don't have =(

thanks!
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Old 05-04-11, 09:31 AM
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Sounds like it could be your cable tension that needs adjusting? (As well as the limit screws). If they are twist-grip shifters, then there's probably a barrel adjuster right where the cable goes in - if the cable is too slack/tight, then it won't shift to the correct gear when you twist the shifter.
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Old 05-05-11, 06:03 PM
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llmercll
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Sorry for the delay. I've got no tools or pump so I need to put this project on hold until I can get ahold of some.

I'll be back with pictures once I have the tools I need =)

thanks
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