Yes -I have made and used various reduction units
among em two Wankels on on center pylon- very smooth setup 2-1
the OS .61 internal geared setups with "hunting tooth" setups -very noisy with irritating warble due to changing exhaust/prop positions
very powerful-for their size -easily the best production setup we also piped em for 16000 rpm and ran 15x10 props!
The gasser setups - with poly V belts
- heavy clumsy etc..
anyway
I hope the guy gets enough power for the 41"prop.
The French adaptionof the G62 and a pipe works