Finally found ways to have all three belts on the twin jackshaft 40:1 ratio motor bike have tensioning capability so that belts are not popped onto pulleys stressing both belt and pulleys.
A turn buckle tool for the second and third belts, while a back side idler pulley is used on the first belt get the job done. Shims made of keys for pulleys, but I instead cut and shaved to shape are used to limit the tension on the 2nd belt. It is so that I get the exact same position on the bottom jackshaft (which is slotted to allow tensioning belt) and know that the bearings are running smooth.
The shims stay in place with fender washers, while the turn buckle tool is used and then removed before operation of the motor bike.
Art Fish Mobile Motor Bike prior Motor Bike DIY'er build to add side car maybe?
post 119 an 120 for all pictures current