Will a m900 rear mech work in 9 speed setup??

[FluffyChicken]

MAX was 32 as that was as high as M900 cassettes went up to, by adjusting the b tension it should clear a 34 fine. Most mechs will go a tad over their state max capacity

34 is hugh though, stick to 28 top, it's all you'll need.

The capacity is only 33T though compared to a Long Cage XT at 38T which is the main killer for running 34T effectively.
Saying that iirc a M900 default setup was a 40T capacity (46-26)+(32-12) and I happily ran many years at a 41Tooth capacity (48-24)+(28-11)

M900 chainset should be fine, if it's the original ring then the only problem I can think of is pickup on the ramped teeth working efficiently. But I've never tried with a 9 speed chainset... EDIT oh actually I have as mine setup with one and since I did notice I guess all is good (KMC X9 chain)

I do however have problems running a KMC-X8 running on a modern SLX chainset with a grinding noise that I can only put down to the pickup bits on modern Middleburn chainrings. Going to try a 9 speed chain on it. (using 8 speed cassette)

Hope that's not confused you even more.

... nitty is, give it a go as it should be perfectly fine.

 

[hamster]

There are two separate capacity questions:
1 Clearing the largest cog
2 Wrapping the chain between big-big and small-small

With a medium cage you might be limited on the second (I can just get away with a 11-30 and 22/32/42)

Usually you can get away with both a little beyond the numbers that Shimano give.