Can you put a 70cc pocket rocket engine in a 49cc pocket rocket?

Nope, too much power, will blow the engine. the text above is retarded how can changing the engine blow the engine if a 70cc engine will fit it will work what he's saying is that the rear sprocket is to small. You would have to get a bigger sprocket so the engine won't run at high RPM's when you take off. With the bigger sprocket, the engine will have to work a little more to get the wheel to turn.