Answered Dead rear derailleur?

[BammBamm]

Is my rear derailleur bunk? Looks like the cage is twisted to buggery. Is there anyway to save it, maybe by replacing the cage?

 

[ImSundee]

Yes that should be straight. Time for a new one.

 

[BammBamm]

Thanks figured as much but was hopeful to save forking out money for a new one. Such an expensive habit we have!

 

[Rusty]

I think it looks worse than it is due to the bent derailleur hanger. I would straighten that first then review.

 

[Kaelidoz]

I bought this cheap tool Cyclus Tools Derailleur Hanger Adjustment Tool | Tools - Derailleur Hanger Shop to fix the hanger.

It worked a treat.

 

[steve_sordy]

Bent derailleur hangers are fixed with a hanger alignment tool, and they do it very well. It fixes all sorts of irritating shifting problems that do not respond to other measures.

But your mech itself is bent. I'm not saying that the hanger isn't bent, just that fixing that alone will not solve your problem.

Remove the mech and attempt to straighten the lower section only. Don't hit it with a big hammer, use a sustained pressure. The upper section may also be bent but it's not shown in the photos. Once you have given it your best attempt, then refit and use a hanger alignment tool to sort out the rest of the problems, or get your LBS to do the alignment job for you.

Alignment tools are £35-£60 and they don't look much, but they are the only thing that will do the job well. Once you have bought one, you will have it for life and can use it on any bicycle. I spent £10 at the bike shop on each of 3 separate occasions before I bought an alignment tool. I don't regret spending the money one bit.