rear derailleur bolt stuck

[lph]

Updating to say - I took the derailleur off again, pulled off the c-clip and removed the body screw plate and seal. The spring inside wasn't going anywhere even though I pulled on it hard, nor was the bolt. Full of salt and corroded gunk though. I guess that's what winter riding does to a bike. After a lot (a lot!) of oil and spraying and squeaking and working back and forth until the whole thing was pretty warm, the bolt deigned to wiggle slowly out. It was a close fit, and the inside of the hole was just visibly plated. Scraped it out, trying not to make gouges, greased it up well and lo and behold, the bolt went in again and could be turned by hand.

Reinstalled I could see the derailleur pivoting a little around the bolt when I re-adjusted the gears, so I'm hoping this will solve the mysterious sticking problems back there. I still have the sloppy pulley wheels to replace, but I think they just cause imprecision.

I like taking things apart

[tzvia]

If those jockey wheels are worn, you should also check your chain and cogset, as they may too be worn and cause skipping. A worthwhile tool to have is that Park chain wear checker. It fits over a link and then the other end rests in another link, and if it goes all the way into the link, the chain is worn and should be replaced. Of course, if the cogs are also worn, they should be replaced along with the chain. The derailleur cable is another item that should be changed every year, and if the bike is subjected to a lot of harsh weather/dirt the cable housing should also be replaced.

Hopefully the cleaning you gave that pivot point will help the derailleur's upper pulley track under the cogs and tension the chain properly. I do most of the work on my bikes, and would never think to open that up myself.

[lph]

I have that chain checker, it's brilliant

I've been keeping track of the wear on the drivetrain, but just casting an eye over the jockey wheels, and since the teeth aren't excessively worn I haven't thought about replacing them until now. The sideways play was quite a lot - but I kind of suspect I at some point may have cannibalized some parts from another bike... My commuter bike is sort of put together from the odds and ends leftover from other bikes

Anyway. New jockey wheels it is. But the shifting is already better.