Forum menu
Using an Xt clutch rear mech, oval front ring.
Basically on every full rotation of the cranks the chain changes up and then back to the original gear.
The rear mech has got some play in it, it happens with or without the clutch turned on.
Any ideas or experience much appreciated
I would change the cable and outer and check the chain length.
What is new/old has changed?
possibly a bent/twisted link in the chain if it happens in every gear
Odd question, but do you have a cadence sensor fitted?
I had same problem once on a new chain,turns out pretty much what somafunk says,I'd bent a link whilst breaking and reconnecting so worth checking for iffy links.
Chain has been on for a while, worked ok before so I think the length is ok.
will check chain wear, twisted links and lube it
No cadence sensor.
it just seems to coenside with the position of the chain ring
I'd also check gear hanger alignment / firmly secured.
bent tooth on chainring?
If you can put the bike in a stand so you can see what it is doing.
Spin the pedals slowly and see what the common factor is in changing the gear. Is it the same chain link each time? The same point on the cranks? The same tooth on the cassette? Something is pulling the chain sideways as you rotate the cranks, once you have identified what it is then you can remedy it.
From what you have said, I suspect the gear will change when the oval on the ring pulls the chain tighter, at that point the wear in the mech will allow the mech to twist slightly and change the gear, when the oval slackens the chain the twist is released allowing it to change back.
It only does it in gear 6 and 7. Probably a worn cassette?
Ill put the other rear wheel on and check again.
Thank you for all your advise, it was 2 worn cogs. Great forum😃
Do you need an 11 speed chain whip?
Just wondering if an old one can damage newer cassette’s?
No,I just use a generic chain whip. Should be fine.