They are clever... I had always thought of a shaft drive bike engine along those lines... I would like to see the mount and bearing at the prop end a 'bit more substantial'
but I like the principle
I had thought of a machine a little like a parsons, with the motor under the cofg between the 2 masts... using a shaft drive bike engine with the shaft to one side of the back mast,,, just lock the bike engine in whatever gear gives the best motor to prop rpm....
Imagine when you want to pass your mate in front of you in another gyro, whack it down a couple of gears and zip past him then change up and cruise again.... or change down a gear or two.... then lift the nose and climb out nearly vertical
