Are there any options out there for power meters that would work for MTB and CX 1x setups?
Problems I see:
Crank arm meters for the left arm use arms with less offset for a narrower Q factor.
Spider based meters limit me to certain size chainrings. I would like to run a 32 on the MTB and 42 on the CX.
Spindle based meters would not work due to Q factor.
Power meter pedals (Vector, P1, Assioma) are not really practical to run off the bike (CX) in Look Keo cleats. It’s odd enough and then add the general inability to re-clip when dirty and muddy, and it’s a total non-starter.
Do they share a rear wheel size and OLN spacing? If so, then maybe a powertap hub would work? It’d probably cost as much to build a powertap hub into a wheel you could use on both bikes as it would to buy 2 left crank arms with power meters though.
I think the idea is that a stages for the CX will be a road crank, and a stages for the MTB will be an MTB crank, and you ca’t use 1 crank for the 2 applications because they are different shapes.
There’s nothing really prohibiting the mixed use of a left-only crank arm in some cases. Shimano uses the same spindle interface for their road and MTB setups. One main issue is the different Q-factor spacing. It would lead to a slight offset imbalance at minimum (assuming that chainstay clearance is fine in both applications).
The more limited crank arm length options in the MTB world (no 172.5mm options in particular) is another possible hurdle. It means someone would likely need to use 170mm or 175mm for both applications. Not impossible, but necessary to address.
Depends on the specific bikes and cranks. I move a Stages power meter from my Specialized Crux to my Trek Procaliber and back; different spindle for each bike but it works great.
Friend of mine uses an XT stages left hand power meter on his xc and cx bikes. I think it makes the Q factor wider on his cyclocross bike but I’m not convinced it’s noticeable or particularly detrimental