I think the small Comet is rated for up to 8hp You should be good to go...http://www.mfgsupply.com/gomini/gominiclutch/gominiclutchtorq/gominiclutchtorq30.html .... Curt
LAB
Nice build. I have a cvt go kart drive, not installed yet. Think you need drive and driven parts as the belt is flat on one side.
You could use a go cart centrifugal clutch on your jackshaft, belt or chain model.
Will finish my stretch cruiser build when my Swing Blade Lumber Saw Mill is finished.
Ron