i am making a friction drive motorbike
i am make a direct friction drive motorbike with a bmx bike and a 25cc weedeater i am going to mount it on a hinge and i will use a spring to tighten down the spindle. the hinge is just some angle aluminium mounted to the two bottom holes of the engine. the aluminum is just connected two a bolt that goes over the brake cross section. the spring goes from the end of the angle aluminum to the wheel axle. is that enough or do i need more?