Well, it must be breaking in, because now that I have 25miles on it, it's got more power, running smoother, and top end is 30mph, (may be a little higher, but I'm limiting anything over 20mph to 30 seconds or less). I think this little engine will be GREAT fun, and I may actually use it practically. I really need to get a beach cruiser or something like that, and put a rack or a basket on it. Not cool, but if it can't carry at least a bag of groceries, it's a toy. Right now it's on a skinny tire ten speed (only thing I had). The advantage is the gears are on the headset/gooseneck so I didn't have to remove or modify them, but I don't use them anyway so a beach cruiser is on my list. More comfortable upright riding position.