hello
The gear box is a standard 4 speed box from a villiers 2T or 1H engine, There is no primary chain case so the clutch and chain run dry open. I made a frame that holds the engine and gearbox together and in line. I had to fit a very small engine drive sprocket to gear it down or it would have been geared to go 80 mph. I have only had it to 20 or so in second gear its gear for about 40 but I dont know if the engine would have enough power to pull full revs in top gear. Its very fast to 20 though similar to a 125 motorbike