It is a lot of work, and has to be very precisely done to work
properly. If the rim isn't precisely centered you get a nasty wobble
that can damage the clutch and rattle your teeth out.
If you send the pic to your pictures you can blow it up for
a better view.
What I did there is notch the rim to an exact depth matching the notches
to the spokes,(again I can't over emphasize the importance of being
centered) the depth of the notches is such that when placed on the
wheel there was just enough room to wedge a strip of alu 1/16" between
the spoke and the inside of the rim. these were then secured with
self tapping screws. You've no idea how many arrangements I went through
to arrive at a system that works as well as this one. Success at last!
Oh yes, It is the rim of a 20" bike wheel. This setup can handle a bit more
power than the cogged belt kits. I'm running a 2,2 hp Tanaka 40cc,
very reliable but costly Japanese engine.
Mounting a pullet is not as difficult as catching one