Bent cage/tight pulleys

Cannon71

Hi all,

I've been having trouble with chain-suck on climbs. I put this down to a muddy/failing chain causing it to stick to the granny ring. (I was short of time after that ride, so didn't clean it for 3days. When I did clean it, the chain was rusted through. New HG93 chain fitted tonight.)

However, as I took my rear derailleur (2010 Shimano XT, MD772) cage to bits for a decent clean tonight, I noticed that both wheels/pulleys weren't running freely upon re-assembly. (I'd cleaned them thoroughly with a bit of GT85 then re-greased them.) Due to the friction in the tensioner wheel, there was barely any tension in the chain: so this is probably a contributor to the chain-suck... (?)

I released the torque on the tensioner wheel bolt and noticed that it ran better. Upon re-torquing, the wheel got tight even before the 2 cage halves were fully pulled together.

I should point out that I have bent this cage in the past. I straightened it as best I could and the misalignment, whilst apparent on close inspection, is barely noticeable.

So, what's wrong? Knackered wheels? Cage 'too' bent? Derailleur knackered?! (I'll post images tomorrow when it's light.)

As always, I appreciate the advice, guys!

cooldad

Have you put all the bits back? Including any bushings/bearings/cover plates?

Cannon71

Yep. All spacers, bushes, seals and bolts back in their correct place.

allthegearnoidea

It's possible that the spring that pulls the cage back has spun round inside the cage mech join, without the chain on assuming its a 'normal' mech the cage should snap back under the mech body when pulld forward and released, if not then the inner spring may have slipped, simple enough to do but handy if youve 3 hands lol! Iirc they are still a small allen screw on the side of the mech body torelease the cage??

It does sound like your jockey wheel isnt quite right too, upgrade time to shiny ones;-)