"Pete Biggs" t wrote in
message ...
Michael Press wrote:

* Probably should install a new chain.

A new derailleur does not need a new chain, and a new chain may not
work with the old sprockets if they are well worn.

~PB

But if the derailleur was "all bent up" as described in the original
post, it's quite possible the chain might be twisted, or that it could
have been a separating link that caused it. In any event, checking the
chain for damage (twists or tight links) as well as wear would be a good
idea.

--Mike-- Chain Reaction Bicycles
www.ChainReactionBicycles.com