I marvel as much as the finished look as the mechanical works and how it was accomplished, close tolerances and all.
If I don’t try for a hovercraft with an extra junked 6.5 vertical Briggs I trash picked, when I get finished with building the dirt motor bike/ fish art motorbike , I may like to know where you got the gear box. This way I might go with some wheels at all and maybe four.
What kind of gearing down does the box do beside the axis of rotation change? Also the overall ratio, what it is from the engine crankshaft to drive axle without the rear wheel diameter yet counted in. Then of course the wheel diameter and what you get in speed range with rpm’s range.
The belt centrifugal clutch looks exactly like the one I am using on my motor bike. I have barely got it to grab the shoes fully as I had only 8:1 ratio with 26 inch wheels. That is practically done for the dual jackshaft that is about 50:1 and with change one pulley to get 25:1 for non-parade dirt biking.
The pulley that goes to the input to the box looks to be about eight inch diameter that would give a fair amount of needed lowering ratio.
MT
http://motorbicycling.com/showthread.php?t=29678&page=4