Chain compatibility

[Turborider]

Hi
I run a shimano 9 speed cassette and am looking to replace my chain. I have been given a kmc 10speed one by a friend. Will it work on the 9 speed system?
Thanks

[Bill]

Recently I had a problem with a KMC chain 5-6 speed fitting on a 7 speed and it did not work, I looked in the KMC site and it does not look like they are compatible. 10 speed chains are meant for 10 speeds and 9's the same way. From what I understand is that the more cogs you have on the back the difference in wall width is the problem.

[cyclerUK]

If it's not costing anything then try it.
Usually KMC have a "quicklink" so joining is easy.
Don't cut the chain smaller until your sure it works O.K.
Make sure the chain sits properly in the "valley" of the sprockets and chain rings.

A 10 speed chain will be more expensive than a 9 speed of equal quality ao would be a waste of money if you bought one.
A 10 speed chain is internally narrower than a 9 speed.

[Alex Wonner]

Well, I had the same problem when I changed my cassette. I thought ( I assumed!!!) I had a cassette with 8 gears and I had in fact 9 gears! It didn't work when I change the cassette! Why? I don't know. So I put back the old one (I'm living in a remote place so I will have to wait to replace it again).
Try and see. Alex

[jr14]

The 10 spd chains are so narrow I doubt it would work on a 9 spd. I haven't run into too many compatibility issues with 8 to 9 spd and vise versa, but a lot of the 10 spd components can be finicky.

Doesn't hurt to try though. Throw it on and see how it works. You'll be able to tell immediately if its incompatible.