I had a pair of 49cc Yamaha Razz scooters in college - an '87, and an '89. The fastest I ever got them was somewhere between 33 - 35 mph going slightly downhill. Usual top end cruising speed on level ground was roughly 30 - 31. Unfortunately, that's the closest thing to a motorcycle I've ever owned.
Was fun fixing them though - at one point, I had a ground floor apartment with a sliding door, so I'd break down boxes, lay them all over the carpet, and wheel them inside my living room to work on.

This was especially nice in the winter. Yes, I rode them year-round, although they didn't run that great when it was really cold out.
I've thought many times since then about getting a real bike, but the complete retardedness of the drivers out here has always made me reconsider. Maybe one day though.