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  1. #1
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    38/26 t M980 XTR Chainrings on M970 XTR Cranks

    Just finished converting my 2007 FC-M970 Crankset 44/32/24 to 38/26 using FC-M980 Chainrings !

    Parts Purchased ;

    FC-M980 38T-AH Chainring part # Y1LR98030
    FC-M980 26T-AH Chainring part # Y1LR26000
    FC-M800 FIX Bolts Part # Y1FB98010 only used 4 mm spacer from kit.

    M970 Chainring thickness 1.96mm
    M980 Chainring thickness 1.88mm this is only .0003 " not any differance !

    I mounted the 38t using the stock lenght M970 XTR bolts and placed the above chainrings spacer under the head to fill the gap left by the removal of thhe 44 t large chainring this has a 4 mm thickness were the bolt goes throught the chainring, then mounted the 26 tooth chainring.

    The M980 26t chainring has the exact same offset as the M970 22 or 24t Chainrings (2.1mm) Used my M970 XTR shifter and FD-970 XTR front Derailleur with only a small height adjustment. Just got back from a quick test ride and shifts great maybe a little smoother !

    The small to middle spacing is exactly the same !

    Weights 38t-79 grams / 26t -36 grams / qty Alum 4mm Spacers 2 grams for a total of 117 grams, M970 44/32/24= 156 grams / 44/32/22 = 148 grams so I saved 39 grams !

    Pictures to follow left my camera at work. Very easy 2x9 conversion with a little research for the right spacers, I tried to fine shorter bolts however I was not able to fine the short female side that would be required. I think the stock M980 FIX bolts would work exept they were $$$ 68.00 for the set !

  2. #2
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    Do you have some pics of the setup? I have two m970 cranksets, very interested in this setup. On my AM rig I'm running 36-26 with SLX alu rings and some cheesy spacers on the granny. Front shifting just isn't the same as with the stock XTR, I can't seem to avoid getting chainsuck. Also wondering if you have room to run a bashguard?

  3. #3
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    I just swapped over the chainrings on my very used 970 crankset to the 38/26 double setup with a lightweight BBG bashguard. Picked up the rings at Universal, they are a bit spendy but way cheaper than a new 985 crankset. I got years of heavy use out of my original 970 rings, hoping to get the same out of these. These rings just fit without having to use spacers on the granny ring to compensate for the XTR chainring offsets. Thanks to Spin Cycle for finding this out.
    Attached Thumbnails Attached Thumbnails 38/26 t M980 XTR Chainrings on M970 XTR Cranks-shimano-001-653x800-.jpg  

    38/26 t M980 XTR Chainrings on M970 XTR Cranks-shimano-002-800x600-.jpg  


  4. #4
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    will XT chainring fit on the m980? I want to put a 24,32 xt, bash onto my m980

  5. #5
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    I think it should work, but you would want to use the XTR 24t granny to avoid using spacers. I think the XTR middle ring has a slight non-standard offset as well, so you might want to stick with XTR rings for perfect shifting.
    My setup posted above has been working flawless. Eliminated my chainsuck problems, and front derailleur shifts are super smooth, even under load.

  6. #6
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    Is that a Remedy frame?

  7. #7
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    yep

  8. #8
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    Any chance you can post a photo without the BBG bashguard, keen to see the 38t exposed. Thanks.

  9. #9
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    Quote Originally Posted by Bones2 View Post
    will XT chainring fit on the m980? I want to put a 24,32 xt, bash onto my m980
    Probably not. I got some used XTR M970 chainrings, 22/32t, to put on my new XT cranks, because I wanted the 22t granny and I figured it would save a bit of weight. But the spacing was wrong and they didn't work on the XT cranks. The spacing between the rings was wide enough that the chain got jammed in between them.

  10. #10
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    Just fitting same setup on a customers crank in store.
    Has anyone else had to cut the Chain drop pin off to fit a bash?

    Cheers
    Rick
    God....whatever i feel like doing!!!

  11. #11
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    Nope, but my BBG bashring has space for the pin.

  12. #12
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    Cheers Strader,
    Saw this.
    anyone else?
    God....whatever i feel like doing!!!

  13. #13
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    38, 24 rings and which front mech?

    Just a follow on....
    I run and have for a while 38 + 24t chainrings on XTR cranks, these aren't XTR dedicated rings but a 38t gamut ring and an XTR 24 t ring inner.
    I run them with a raceface lightweight bash.
    At the rear I have Sram X9 with an XT 10 speed cassette 11-36.
    Here is the thing, it all works perfectly apart from my SLX front mech has just give up,it's a double specific older model modified to fit the frame.
    So, I have just bought a FD-M786 XT 10-speed double front derailleur, conventional swing, black to replace with.

    Will it work?
    Nope!
    I really dont understand, it's modified as it should be to accommodate the link, it's adjusted correctly, correct cable tension etc. but it will not take that chain from the 24 to 38t ring no matter what I do.

    I have refit a newer slx front mech from my hardtail and boom, it works straight away.

    I'm confused.
    Anyone else had similar issues?

    Just to clarify any issues with chainring combos Shimano have just released a 38, 24 XT dedicated crank.

    Help!!!
    Rick
    God....whatever i feel like doing!!!

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