Stumped by a problem here.
Was riding a few times this week uphill, standing on the pedals and pushing hard, and the chain made a bang and I believe slipped?
I put it up on the stand to figure out what is wrong, and everything looks ok, except for when the chain is on the largest cog – it's knocking or quivering.
I've played around with the l limit screw, the b screw and the barrel adjuster and I can't make it go away.
I recently upgraded my 8 speed set up to a 9 speed (11-34t cassette, with a Sora medium cage derailuer, new chain (9s) and new shifting cables and housing). All of that gear is less than 2 months old and I've only been experiencing this for the last week)
Any ideas?
Rear derailuer knocking on largest cog
byu/anabolic_beard inbikewrench
by anabolic_beard
4 Comments
Might need to ditch a link or two from your chain. Had this problem too. I’m that case, I could see the upper jockey wheel contacting the biggest ring on the cassette.
Is your chain routed inside the little tab by the upper pulley wheel and not outside?
https://preview.redd.it/q8d7864j203f1.jpeg?width=856&format=pjpg&auto=webp&s=c6df50819bcbe1cda539cb2d766f6c40c1b1b321
Definitely not routed correctly
I need to see what’s happening where the chain leaves the jockey wheels and meshes with the cassette. I know you said you’ve messed with lower limit screws and barrel adjusted tension, but from the sounds of it, it seems like the chain is having trouble staying on the largest cog due to derailleur not being aligned either because of tension or lower limit.