I am a 70 year old man who likes to tinker. Was getting a little bored so I started watching you-tube videos and ran across this subject. Got a cheap 49cc kit off Amazon. I thought it would give me a day of tinkering but I finished it in about 2-1/2 hours. I have already put 60+ miles on it and haven't even left the neighborhood yet! Top speed so far as been 25.4 mph on level ground. Don't have enough road to stretch it out. In NC motorized bikes have to be registered and I have not got around to doing that. This thing is more fun then a barrel of monkeys!