Sprocket size help

[Seanik]

I recently acquired an OCC chopper and decided to power it with an 80cc 2 stroke slant head. I thought about a 4 stroke but it looks like it would be a tight fit. Also bought a modified seat on eBay that puts the rider back about 9". The chopper has the fat tire 20" rear wheel and was wondering what size rear sprocket to get, most kits come with a 44T sprocket, it seems this would make for a slow ride. At 250 lbs and moderate hills I'm thinking a 36T or 41T sprocket is what I should install to compensate for the 20" rear tire. I would appreciate some advice.
I also have a Schwinn point beach with a dax 4 stroke rear mount and a 48t sprocket that pulls great on the hills.

Seanik

[Creative Engineering]

Sean,

If you want the same ride as your other bike, use a 38T.

Jim