I know this has been asked before but wanted to make sure in case things have changed over the years. I have a brand new Deore M592 Shadow 9 Speed rear derailleur and wanted to know if I can replace my old tourney 7 speed rear derailleur with this without having to change my freewheel and chain. I am planning on converting it completely to 9 speed eventually but not right now.

4 Answers 4


Below 10-speed, specs have very stable and haven't changed over the years (above 10-speed, specs are also stable, but there have been some bifurcation between road and MTB, and between brands). The change has be done in one operation and cannot be done progressively.


The rear shift ratio (pull ratio) of Shimano 7,8 and 9 speed derailleur is same 1.7:1

So the specs say it should work.

Please update us with how it works in practice.

  • Hi, welcome to bicycles. This seems more like a comment on one of the other posts than a complete answer on its own. Please only post full answers; you might want to take the tour.
    – DavidW
    Commented Aug 20, 2023 at 19:44

My Kona from the factory came with a 9 speed Alivio rear derailleur and 8 speed shifter and cassette, so that indicates that you should be compatible.


No, it's not compatible and it won't work..

Besides the 9 speed Deore have a narrower cage, the biggest culprit is, pull ratios are different.

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.