Weak springs on Dura-Ace Rear Derailleur?

namastebuzz

Have a Dura Ace rear derailleur that seems a little weak in taking up the chain slack.

Are the springs weak or is it just dirty and full of goo?

Can you rebuild/get spares?

ugo.santalucia

How can I know if it's too dirty?

However, censored shouldn't get into the internal spring... and the latter tends to live forever and after. Is it not the chain which is too long?

When you're on the big ring and a cog in the middle of the cassette, the jockey wheels should be vertically aligned or so... if there is an angle (going backwards) the chain is too long

Monty Dog

You can service many rear mechs - there is often a cir-clip which holds the cage pivot in place - the internals can get gunked up if it's had a hard life. Remove the inner cage / jockey wheels. Wrap the body of mech in a rag and hold in a vice to prise the clip off carefully - hold a rag over the top to stop it pinging off. The outer cage is under spring tension and will want to spring back as you pull it off. Give the inside a clean / regrease and re-assemble making sure you wind-up the spring when you fit the outer plate.

namastebuzz

Thanks Guys

You're right Ugo - you can't know if it's dirty, I meant: Do you suppose dirt might be causing it? JUst fitted a new chain of correct length but thanks for the idea.

Cheers Monty - I'll strip it and clean it as you suggest although I've worked it back and forward a bit and squirted in lube and it's improving already.

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