I just bought a "Baja" style mini bike, (Metal Motors MX 196), with a "clone" 6.5hp, 196cc, Lifan motor with 3/4" shaft. I want to upgrade to a 3/4", 10 tooth, 41 chain, torque converter. Right now it has a gear reduction set up on a pressed steel a backplate with 3 tabs, and 170mm between the...