new chain rattles on rear mech.

craker

I've just replaced a c. 4000 mile chain, possibly SRAM to SRAM but I'm not too sure. Certainly it's a 9 speed that's gone on. Anyway, on the big chainring it rattles in the big cassette gear (as expected and never used) but makes a pretty similar noise to about half way through the rear mech. range, noise from the jockey wheels.

It's a Tiagra triple 9 speed. Obv all was well before the old chain went.

I could try changing the jockey wheels I suppose. Is it likely to wear in? I've done 100 miles or so on the new chain.

sungod

sorry if i'm asking the obvious, but did you take out any excess lnks to make the new chain the correct length?

if the length is ok...

how worn was the old chain? if it went far enough the cassette will be worn on the most used cog(s) which could explain the noise, or maybe just the rear mech needs adjusting

if the chain skips on some cogs when you pedal hard, then the cassette is worn

useful info on chain/cassette wear...

http://sheldonbrown.com/chains.html#wear

The Mechanic

Are you sure you threaded the new chain correctly. It is easy to miss the metal tabs on the jockey cage. This would make the chain rattle and wear out the chain in super quick time. Otherwise it could be chain length as Sungod says.