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Shimano chainset comaptability

Hi all. Happy new year.

I need to replace my Shimano XT FC-M785 chainset (this is cira 2015, 10 speed).

Does anyone know whether I can use the Shimano Deore XT M8000?

NB the shifters are Shimano XT SL-M780-I, and the front mech is Shimano XT FD-M786.

Or does 10 speed have to replace 10 speed?

Thanks in advance :smile:


  • swod1swod1 Posts: 1,639
    Cranksets don't matter so much I'm using an slx m7000 with a 10speed kmc chain on my old xtr 10speed setup.

    The latest chainrings will be fine with 10/11speed chains the size difference is slight between the links etc.

    Just remember to buy boost or non boost and the right crank arm length 170, 175mm etc
  • swod1swod1 Posts: 1,639
    you could save some money if its a 104bcd size and fit a narrow wide chainring?
  • thistle_thistle_ Posts: 6,976
    If you are replacing the crank and the chainrings, no problem. Can't think of any reason why a 10 speed setup wouldn't work with an 11 speed chainring/crank.

    If you were planning on reusing the old chainring, it won't fit: The XT M8000 uses 96 PCD and they are in a rectangular pattern, not square like on the M785. I believe this is so you can fit a 32T chainring if needed.

    Make sure you get the correct chainring when it's time to replace it!
  • That's great, thanks all
  • The RookieThe Rookie Posts: 27,811

    I believe this is so you can fit a 32T chainring if needed.

    As you can fit a 30T to a conventional 104mm, I'd suggest if its for chainring size it would be a lot smaller than a 32t!
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
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