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Rear derailleur won't shift up

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Rear derailleur won't shift up

Old 06-21-11, 10:16 PM
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Rear derailleur won't shift up

Hello. My rear derailleur shifts slowly or not at all onto my two smallest gears. I've replaced the housing and cable and it's all fine. When I move the derailleur back and forth by hand, it feels a bit mushy on the high-gear end (when there is no tension in the cable); it's like the derailleur gets stuck. I cleaned it as best I could, and that wasn't any help. It seems like it's either dirty or the spring inside is worn out. At this point it seems like I would need to either replace it or overhaul it. My question is if it is possible or worthwhile to overhaul a derailleur, and if not, then what would I use to replace it? It's a Shimano "light action" RD-L525. It's for 6-gears, indexed shifting. Thanks for any help.
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Old 06-22-11, 06:55 AM
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If flushing it out doesn't help, and it's properly aligned, then it needs replacing.

Soaking it in degreaser or kerosene will clean it out.

Eyeball it from the rear and see if the cage is aligned with the cassette. It's common for them to be bent toward the wheel.

Most Shimano indexed derailleurs will work (5/6/7/8 speed if I remember correctly). It just has to be made for the same spacing on the cassette as yours. The shifter controls how many speeds it is.
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