I’m going to be ordering a new CX bike which comes with Sram 1by drivetrain. I’d like to put my shimano dura ace stages power meter on to it. I know it won’t fit onto the Sram chainset. What 1by shimano chainset could I use? I see there’s an XT 1by but it doesn’t have 40T option. And also if there was an XT option, would the dura ace crank arm not sit out wider giving pedals/crankarms a different distance from the BB? Thanks

Any Shimano road chainset should work, MTB chainsets are wider. A triple may give a better chainline, but I use the inner position of a double with no problems. I think you will need to change your BB to suit the 24mm Shimano axle.

I don’t want to have a double chainset on and I’m not sure if there is a double that would have a 40t inner ring. As far as I can see there’s nothing off the shelf from shimano that would work, thinking the only option might be a crank arm fitted to a single ring from another manufacturer with the same BCD

As far as I can see there’s nothing off the shelf from shimano that would work, thinking the only option might be a crank arm fitted to a single ring from another manufacturer with the same BCD

correct.

You will need a new 24mm bottom bracket, Shimano road crank set and a single ring with an appropriate BCD from Absolute Black/Superstar/BETD/other.

A road Stages won’t fit nicely on an MTB crank and a Dura Ace stages will only fit on a Shimano road crank nicely. If you want to run your PM you will need to bodge a single ring onto a Shimano double.

Are you worried about the chain line? Just space the ring.

Space what ring?

Thanks, double chainset crank arm onto single chainring sounds like the answer. Will see what I can do.