Derailleur setup

[GoodRiddance]

I've setup my bike, made sure the derailleur is straight and it runs smoothly along the cassette.

Now strangely, while it looked to be smooth and running well, it goes wrong for the upper derailleur wheel. Somehow it starts to mess around there while the chain is nicely tied to the cassette.

I've filmed it to make sure the problem is clear, I hope someone can help. What should I do to fix it?

[youtube]https://youtu.be/QknOGP427sM[/youtube]

[reohn2]

The link doesn't work.

[Brucey]

is the top pulley binding? Is the bushing in good condition? Are the teeth on it OK?

Have you changed anything lately?

Have you checked the chain for stiff links?

Has anyone else looked at it in person?

cheers

[irc]

The link doesn't work.

Works for me. Hard to see what's going on from that angle though. Shots from directly behind and from the side might help.

https://www.youtube.com/watch?v=QknOGP4 ... e=youtu.be

[73Chaz]

Possibly a stiff or bent link in the chain?

[gregoryoftours]

It's a bit hard to see what's going on - it almost looks as if the jockey wheel itself is wiggling all over the place - can you wiggle it about side to side a lot with your fingers? There's a bit of side to side play in some shimano jockey wheels but that's usually the other pulley to help with shifting. If tension pulley in the video has a lot of side to side movement there's something up with it.

[Eyebrox]

Have you replaced the bottom jockey wheel without the heavy centring washer. Top left in pic.