I have replaced my Alivio rear derailleur with a new Deore M610 but it doesn't shift properly. The casette is a 9 speed Shimano Alivio CS-HG400-9 11-32T and the shifter is an Altus. Do you think this combination would be operating well if set correctly?

2 Answers 2


The M610 is a 10-speed rear derailleur and is not compatible with 9-speed cassettes and shifters (different pull ratios between 9-speed and 10-speed).

If you want to stay in 9-speeds and Deore, compatible derailleurs are RD-M591 and RD-M592, but they are getting hard to get. You also have other options from other brands.

If you want to keep the derailleur, you'll need a new shifter, cassette and chain. 1-speed deviations are OK for the chainrings and front derailleurs. You can find the compatibility chart here.


10 speed Shimano mountain rear derailleurs are not compatible with 9 speed cassettes and shifters. However 10 speed Shimano road derailleurs are compatible with the 9 speed cassettes and shifters.

I have been using a Shimano RD-5701-GS 10 speed mid-cage rear derailleur on a 9 speed touring bike for some years now because I couldn't source a RD-M591.

Going from 9 to 10 cogs, Shimano changed the pull ratio for 10 speed mountain bike derailleurs, but not for the road derailleurs.

The one exception is Tiagra 10 speed, which has the same pull ratio as the other Shimano road 11 speed shifters.

Unfortunately the Sutherland manual that professional mechanics use as a resource didn't pick up on this point.

  • Hi, welcome to bicycles. The question. Is specifically about Deore; are you saying that road groupsets are compatible with Deore?
    – DavidW
    Feb 24 at 12:10

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.