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  1. #1
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    XTR M980 38/26: new chain rings and 38/24 combo

    My crank set is the 2 ring "trail" version with 38/26 rings.

    Are there any other chain ring companies out there who make a set to fit this crank set? If so, please provide a link.

    Also how is the shifting if I drop from a 26 tooth small ring to a 24 tooth small ring with a 38 tooth big ring?

    Last, I assume I should replace the mounting bolts and nuts every time when new chain rings are installed?

    Thanks!
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  2. #2
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    I've not checked, but Blackspire often does shimano specific rings where no-one else does.

    Bolts and nuts are all reusable.
    You might have a slight bit of hesitation by comparison to the 2T smaller jump, but shimano FD's shift well enough to make this not an issue.
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  3. #3
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    Quote Originally Posted by ambassadorhawg View Post
    My crank set is the 2 ring "trail" version with 38/26 rings.

    Are there any other chain ring companies out there who make a set to fit this crank set? If so, please provide a link.

    Also how is the shifting if I drop from a 26 tooth small ring to a 24 tooth small ring with a 38 tooth big ring?

    Last, I assume I should replace the mounting bolts and nuts every time when new chain rings are installed?

    Thanks!
    I've been on the fence about going with the 980 38x26, coming from a 3x9 970 setup.

    Is climbing with your 2x10 painful?

  4. #4
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    Here you go: Blackspire - SuperPro M980X Chainrings | Blackspire
    which says the gap between 38 and 24 is too large..max 12 tooth diff.

  5. #5
    Ted
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    I am running an XT M785 crank at 38 and 22. It works fine with a shadow XT M780 rear der.

  6. #6
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    There is a new fc-m785 with 38-24. The 38er has a special design for better shifting

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  7. #7
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    The OP has a FC-M980, I doubt he is willing to change it...

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  8. #8
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    OP???

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  9. #9
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  10. #10
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    Quote Originally Posted by bikecore View Post
    OP???

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  11. #11
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    th 980 uses standard 4 hole size rings 64, 104 so just about any 4 hole 64mm granny will work. if you want langevity action tec has Ti .
    the key will be if the deraillier will work. you need something that will lift a 14tooth diference., check your front deraillier specs, it will list what it is capable of.
    if its less that 14t then you will either have to get a 24t granny or a 36t big ring

    edit
    just checked shimanos web site
    985, 985E not E2, 986, 986D, 980, 981 all will work, says the 980 series will throw an 18t diference

  12. #12
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    I wish Shimano would make a 28t inner ring for the 980. I feel the 26 in my case could be a bit higher. I'll probably just get another brand 28, but it would be nice if Shimano made one in the same forging as the 26.
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  13. #13
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    I'm running an M985E2 up front so I guess that seals the deal for me. Gonna stick with 38/26. It's been fine for me anyway. Just that occasional +15% grade grind that hurts. But I'll live.

    Thanks for all your input guys!
    ...and proud member of the anti-sock puppet desolation

  14. #14
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    The m970 chain rings should fit because I'm running m980 chainrings on m970 crank it's a direct swap. I use it at as a double with a bash ring. But with that gearing I bought a large 39t rear cassette cog from action tec but I rarely use it It's just insurance for the extra long climb

  15. #15
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    Quote Originally Posted by jochribs View Post
    I wish Shimano would make a 28t inner ring for the 980. I feel the 26 in my case could be a bit higher. I'll probably just get another brand 28, but it would be nice if Shimano made one in the same forging as the 26.
    .
    the granny doesnt have any ramps or pins so any brand with a 4 hole 64 bhd will work, if you use it alot I would go with actiontec Ti
    Action Tec Home Page

  16. #16
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    I have a stock FC-M980 with 3 chainrings (24-32-42) and I would like to convert it to 2 chainrings setup for my 29er. I will use chainrings 24 and 36.
    My only quesiton would be that, should I buy the XTR Gear Fixing Bolts (M8 x 10.65) & Nuts (4 sets) (code: Y1LR98120), or will it work perfectly with normal aftermarget M8x6.5mm bolts and nuts?

    XTR version:
    XTR M980 38/26: new chain rings and 38/24 combo-32403_1_shimano_kettenblattschrauben4-armxtrfc-m980.jpg
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  17. #17
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    I still haven't found the answer but found a cheap alternative to Shimano (** KCNC), maybe it can be useful for those people who are thinking on the same question like me.
    XTR M980 38/26: new chain rings and 38/24 combo-xtr-m980-conversionkit.jpg

    A possible source (Germany): Bike24 - KCNC Chainring Conversion Kit 3-speed to 2-speed for XTR 980
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  18. #18
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    Quote Originally Posted by dan0 View Post
    .
    the granny doesnt have any ramps or pins so any brand with a 4 hole 64 bhd will work, if you use it alot I would go with actiontec Ti
    Action Tec Home Page
    XTRs (980/ 970 at least) will not take any old granny. They have a different offset. You can just about achieve this with careful use of washers and standard rings but Blackspire and possibly others make some XTR specific granny rings.

  19. #19
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    Quote Originally Posted by Ted View Post
    I am running an XT M785 crank at 38 and 22. It works fine with a shadow XT M780 rear der.
    Running the same thing here.

  20. #20
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    Quote Originally Posted by cl.mustard View Post
    XTRs (980/ 970 at least) will not take any old granny. They have a different offset. You can just about achieve this with careful use of washers and standard rings but Blackspire and possibly others make some XTR specific granny rings.
    The correct spacing is ~2mm, for those who want to go the spacer route.

    -D

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