Trouble shifting into highest gear

Paul C, Devon

Hi

I have recently experienced trouble shifting into the highest gear (50/12) on my bike, the rear deraileur is reluctant to shift onto the 12t rear sprocket - and when it does it is decididly noisy!

When in the smaller chainring (34t) it shifts cleanly across the whole block but not when I am on the 50t chainring (obvously I don't use 34/12 as a gear when riding!)

Any ideas/solutions gratefully received

Paul

markos1963

It could be that the rear gear cable is too tight but that wouldn't explain why you can get 34/12 and the same goes for your limit screw being out of adjustment. Have you dropped the bike recently or put it in a car etc, you could have twisted the mech slightly out of line hence the strange problem.

Stuck on a Giant

Is it definitely the rear mech making the noise? or the chain rubbing on the front mech?

Is the chain long enough, might be stretching out the rear mech a bit? But that should cause more problems in the bigger cassettes.

I'd try either loosening the cable stop or the adjuster stop on the mech a 1/4 turn and see if that cures it - time to start fiddling?!?

John.T

Just ease the high limit stop a little then make sure that there is not much tension on the cable. If this does not sort it something is siezed or bent.

Paul C, Devon

Thanks for the tips guys - I adjusted the high limit screw and tried the bike today and it was fine

Thanks again