In answer to the top speed question.....I'm smart enough not to have found out :evil:
6" hard rubber tires, 29cc 2 stroke (it's been souped up a bit for higher compression, tuned exhaust and a high performance carb). It's a bit of a rough ride on the road, but between our house, our commercial space, and our local diner the roads are wide with no one parked on the side of the road, so I routinely ride it a couple of times a week for a couple of miles.
The brakes are sketchy...just some spongy metal calipers that grip the front wheel (it is safer if they don't work, although I do use them to keep speed down going downhill...I go faster uphill).
The drivetrain is...none really. There is a knurled bar that comes off the crankshaft that rubs against the rear wheel to spin it. It is much better for me with the clutch and rope start than stock (direct drive, no idling...to start the engine you kick off on the scooter and hope it starts).
In any case, this is what happens when your parents take away your skateboard because it is too dangerous :mrgreen: ...and when you are too chicken to get a motorcycle (although I'm sure mile for mile a motorcycle is safer, I'll go a lot less mile on this thing).
It feels halfway between flying and falling...I try to lean into the flying part :)