I'm quite interested to see how this concept pans out having built
a petrol engined spinner myself for the series 6 of Robot Wars (auditions)
My spinner was a vertical but was more like a steel proppellor blade
and spun in front of the robot as such, it was running off a briggs
n stratton lawnmower engine which drove a heavy hub disk brake
and 50mm thick steel proppellor and a grinder addition.
I'm interested in how you intend to keep it running upside down
ie when its flipped, how you will cope with the fuel limitations 200ml
I think-you will need a Rc controlled electric start because its bound
to stall, It will have to be braked and if its not automatic you will need
a way to operate the clutch.
Interesting prospect but not an easy build.