Two strokes get their power from rpm's. 4 Strokes just have power. example, ever stick your finger in the prop of a 2 stroke running 4000 rpm? "might cut you a little" Try it with a 4 stroke running 4000 rpm. you'll have nubs

"WARNING" DON'T TRY THIS AT HOME! "WARNING"

Thought I would throw a little fuel on the fire