Just curious, Would there be any downside to modifying a 150 mm axle to fit 135 mm dropouts? Understood that you would need to run a single speed free wheel instead of a cassette.
i don't see a downside as long as it's lathed properly and fits snug
i was considering doing this for the clyte 5403 - since there's 2 versions 135 & 150mm
135mm is hard to find so my only option would be to lathe it to 135
Should be fairly easy to cut the axle shoulders deeper. If only one side can be made different, then you may need to dish the wheel to center the rim. A lot of dish is not as nice as no dish on a wheel.
If the motor takes a cassete, it will not be possible to substitute a screw on freewheel.