One explosion per crankshaft revolution on a 2-stroke. The 4-stroke fires every other rotation of the crankshaft. The rest of the time, it's just "coasting."
Don't forget that you also don't have valves, camshafts, cam chains, etc to rob the engine of power. They're also tuned to a much higher level than your average "diesel". How often do 4 stroke guys talk about replacing their cranks and pistons? Sean Jordan Novice #230
Yeah, but if you want to start getting technical, you also have a lot of inefficiencies in the 2-stroke as well, such as burning oil with your gasoline, mixing your fresh intake charge with burnt gases, etc... which probably reduce the output of the 2-stroke. But don't quote me on this, I'm definitely no expert in the matter. However, I think doubling the number of explosions is the main factor in generating more power out of 2-stroke.
Okay, Sean, how about the relative lubrication efficiency of gasoline-diluted two-stroke pre-mix oil vs. undiluted synthetic oil in a four-stroke? How does that affect your theory of parasitic power loss?
(Me, peeking from behind JU's shoulder) "yeah, that's what I said, punk. Who's the man now? Who's the man?"
Thank you to erickson for the link to how stuff works. It made it a little more simple. I guess the bottom line is like a GP bike it is Purpose built. A two stroke engine is designed to be small compact and produce HP.
