The gearbox is mounted between the back axle and the sprocket shaft for the chain drive.
2.
A roller ( a metal wheel with a rubber surface vulcanized to increase its grip ) on the front sprocket shaft was pressed against the machined rear surface of the engine flywheel, thus driving the sprocket shaft, the drive chains and the rear wheels.
3.
A roller ( a metal wheel with a rubber surface vulcanized to increase its grip ) on the front sprocket shaft was pressed against the machined rear surface of the engine flywheel, thus driving the sprocket shaft, the drive chains and the rear wheels.