2

This is a shimano ultegra 6700 rear mech.

The swing arm/cage is incredibly stiff where it connects to the derailleur. I can just about rotate (red arrows) it a small amount but requires a lot of effort.

enter image description here

I tried to loosen up using an hex key (at the blue arrow), but it seems incredibly soft and I think I may have rounded out the thread, it would not budge.

What can I do? Without any motion in that mech cage means that when I shift into the higher gears on the cassette, it doesn't take up the slack in the chain, causing it to drag along the frame and close to the ground.

Improve this question
1
  • You can try dousing it with solvent, but most likely it will need to be fully disassembled (or replaced). Likely there's a spring inside that has wedged itself into the moving pivot or some such.
    – Daniel R Hicks
    Feb 25, 2014 at 20:49

2 Answers 2

Reset to default
1

Get some WD40 or PB blaster and just shoot the heck out of it. Do this a few times while manually moving it with your hands and it should start moving again. Throw some chain lube in there afterwards to keep it moving nice and clean.

Improve this answer
4
  • Let the PB blaster sit for 10 minutes, then apply more PB blaster, then give it a go. Avoid WD40.
    – Scott Hillson
    Feb 25, 2014 at 20:38
  • Yeah, PB is more ideal, but you're more likely to have some WD40 lying around and in my experience it works just as well in situations like this
    – Booker
    Feb 25, 2014 at 20:48
  • @hillsons Why avoid WD40? Any good reason?
    – arne
    Feb 26, 2014 at 11:15
  • As a general guideline, I mean. If you're in a tight spot and WD40 is easiest to reach, then do what you need to do, but I wouldn't necessarily recommend it based on experience and other's opinions.
    – Scott Hillson
    Feb 27, 2014 at 0:09
0

Try using something like Gt85 to get rid of any muck that may be inside, this normally works but if it does not then try a thicker bike oil but would not recommend taking it apart any more as some of these bolts can be incredibly soft and easily brocken.

Improve this answer

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.