XT M8000 1X 165mm boost cranks

The Duckmeister

Has a juicy midrange
Yep. Same cranks for 1x and 2x. 1x chainring has a different offset to achieve the right chain line.
Of that I wouldn't be so sure.... Shimano have typically produced their cranks so 1x, 2x big and 3x middle have all been on the same chainline. Which then leads to another suggestion posed earlier about just stuffing the ring on the outside of an older model/3x crank to compensate for the Boost adjustment... Given the difference in chainline between normal & Boost is 3mm, that would actually be an over-compensation, as the mount tab on the spider is about that thick, then you add the chainring thickness..... I'd imagine that would behave very badly on the big sprocket.
 

EsPeGe

Likes Bikes and Dirt
Of that I wouldn't be so sure.... Shimano have typically produced their cranks so 1x, 2x big and 3x middle have all been on the same chainline. Which then leads to another suggestion posed earlier about just stuffing the ring on the outside of an older model/3x crank to compensate for the Boost adjustment... Given the difference in chainline between normal & Boost is 3mm, that would actually be an over-compensation, as the mount tab on the spider is about that thick, then you add the chainring thickness..... I'd imagine that would behave very badly on the big sprocket.
Don't do this to me!!!! I'm actually waiting to hear back from chain reaction to see if it's the case but I had thought I was all good. It pedals and shifts fine.
 

Ultra Lord

Hurts. Requires Money. And is nerdy.
If anything, having the sprocket mounted normall would help chainline on the big ring. My non-boost set has a terrible chainline in 1st, to the point it actually creates abit of drag. This is with the xt sprocket with 1x offset.
 

EsPeGe

Likes Bikes and Dirt
Of that I wouldn't be so sure.... Shimano have typically produced their cranks so 1x, 2x big and 3x middle have all been on the same chainline. Which then leads to another suggestion posed earlier about just stuffing the ring on the outside of an older model/3x crank to compensate for the Boost adjustment... Given the difference in chainline between normal & Boost is 3mm, that would actually be an over-compensation, as the mount tab on the spider is about that thick, then you add the chainring thickness..... I'd imagine that would behave very badly on the big sprocket.
It's official, got this from CRC

"You are correct in that Shimano do manufacturer their listed Single and Double (1x/2x) crank arms and spider with both sets of bolt holes. You can basically use the Single crankset as a double if you ever wished to do so, otherwise just ignore those inner ring holes and fit a Single specific ring and you are good to go as a 1x crankset".

The bike rides fine and there is absolutely no shifting issues so I guess it doesn't really matter that much.
 
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