2x10 Shimano M785 C...
 

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[Closed] 2x10 Shimano M785 Cranks - What's the smallest outer ring i can run?

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Hi All,

I'm keen to drop my 38T outer chain ring down to a 36 / 34 / 32T ring. Race face seem to have 36 + 34T options but i'm not sure if they offer a true 2x10 outer ring in either size. also, will it effect my M785 2x10 Front mech if i drop sizes?

Any input welcome, thanks


 
Posted : 09/08/2013 5:57 pm
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I swapped out a 32t Shimano XT FCM770-10 speed ring for a 36t SLX 9 speed and noticed no change in shifting performance.

You can always drop the front mech a mm or two if it's a problem, I'm currently running a M785 2x10 with 24 -36 rings.


 
Posted : 09/08/2013 7:06 pm
 mboy
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Your front mech will be fine...

However your cranks will not. You'll need to swap them for a conventional triple, but ditch the outer and middle rings and put a middle of your choice on instead.


 
Posted : 09/08/2013 7:45 pm
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dirtydog, you're running the same m785 double cranks as me. Is your 36t ring the SLX 9 spd you mention?


 
Posted : 09/08/2013 9:49 pm
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No mate, I'm running triple M770 10 speed cranks with the M785 double specific mech, 24 - 36 rings and bash. The 36t is a 9 speed SLX middle ring and it works fine with my 10 speed setup.

I'm not sure what the issue with your crank is, Mboy?


 
Posted : 09/08/2013 10:21 pm
 mboy
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I'm not sure what the issue with your crank is, Mboy?

The OP is running XT double cranks currently. Smallest "big" ring they can take is a 38T.

If he switches to conventional triple cranks such as you and I run, he can run whatever size middle chainring he likes down to a 32T.


 
Posted : 10/08/2013 6:25 pm
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On an XT double the smallest is a 33t, otherwise the chain fouls the tabs in the outer position


 
Posted : 10/08/2013 6:39 pm

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