4g gearbox

I'll start my first build next week. $422 Fito Modena GT-2 7-speed cruiser with 24" x 3" tires and dual disc brakes $381 49cc 4-stroke HS142F with 80-tooth 4G gear (bicycle-engines.com) $217 Shift Kit and chain breaker (Sick Bike Parts) $52 Heavy Duty Clutch (Staton-inc) $8 Tire Slime tube...

I was on the Grubeeinc. website and seen this: (last on the right) http://www.grubeeinc.com/USA/images/120805/59.jpg My very first thought was how I was trying to do this already! My second thought was,who sells it? I'm pretty sure that item will be a hot seller. Oh,and there's 2...