is a new chain needed.

coxy17

hi i am having a new shimano slx chainset put on my bike will i need to put a new chain on as the old one will have bedded in to my old chainset thanks

supersonic

Yes, new chain.

GHill

Probably worth checking the cassette too.

ride_whenever

or move over your old rings and run them, then chain, jockey wheels and cassette into the ground...