Originally Posted by
JeffB502
... maybe you could mount the light or the reflector on your left seatstay?
Or mount the light on the gap between the seatpost clamp and the top tube/seatstay/seat tube junction.
It looks like the light mount can screw down onto a smaller tube if needed, too, which would make it a better candidate for the seatstay. That's where I've put a Mars 3.0 on one of my bikes.