Just a wee update here. Some time back, the governor failed internally- the press-fit gear shaft worked it's way loose in the block and threw the whole system off. I epoxied it back in and it was good... for awhile...
And it has let go again. Dang chinese engines! (And no, "Dang" is not the brand name). So- to heck with it- the engine's coming apart again, and this time the governor guts hit the trash bin. I have purchased a new sprocket for the jackshaft to raise the gear ratio- something I was going to do anyway. This will speed up the kart (yay!) and put more a load on the engine for running ungoverned.
And then, on top of it all, I'm going to have my son (toystory2) do as much of the work as possible. So- Drain fluids, remove and disassemble engine, strip governor, reassemble engine, remount engine, fab new throttle linkage, regear kart. This should prove interesting!