RE: SuperFly meets UltraFly
The B-series outrunner brushless motors from Ultrafly are a good match for small parkflyers like the Great Planes Flatouts and Ultrafly Extra 300. All three winds are 180 watt class motors that can handle various prop sizes from 6" to 11" depending upon the wind (or last number).
The shaft diameter is 3.17mm and you can flip the motor around to use the built-in prop-saver adapter.
I'll test the new motor out in the SuperFly wing and post a video soon.