Friend of mine has this Diamond Back and we want to do some restoration to it starting with the rear mech. It seems to me it has more tension that it should but I might be wrong. Any ideas? 🙂
by Cuervoazulado
Friend of mine has this Diamond Back and we want to do some restoration to it starting with the rear mech. It seems to me it has more tension that it should but I might be wrong. Any ideas? 🙂
by Cuervoazulado
6 Comments
Slightly rusty pivot point – Needs some cleaning and oil. Can use wd40 to clean it, but WD is not oil, so lube it with oil afterwards.
Likely just too short chain.
Looks like it’s toast. There’s a metal tab that limits how far it can swivel back. If the area where the tab rests on the body had been mashed it does what it’s doing.
Possibly dirty, possibly a broken spring, hard to say from the photo. But my money is on grime and dirty prevent it from freely articulating. This happens with my winter bike after a winter of getting as-SALT-ed for a few months.
You can take it off and clean it and inspect it.
However, you could also probably buy a new used dangler for $20 on eBay or at a local bike shop that sells used bike parts (though such stores seem rare these days). That might work better.
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There is a little stop on the derailleur cage that is missing. That cage needs to be given one more turn to increase the spring tension, and that stop prevents it from unwinding. It’s an easy enough fix but it’s also easier to find a used and functional rear derailleur of the same period correctness, or just replace it w something modern that works better.