Whats the simple difference between 2 stroke and 4 stroke?

Whats the difference between a 2 stroke and a 4 stroke? ten points?

• besides power, is there a difference in the kind of gas it takes or how many miles it gets to a gallon or a oil difference? maybe a maintenance difference?

• Answer:

  I won't go into all of the technical differences, you can look that up anywhere on the web by simply typing "2 stroke versus 4 stroke" in a search engine. They take the same kind of gas except you generally have to mix the oil and gas together on a 2 stroke. Yes some have oil injection but you aren't going to see that on a modern 2 stroke dirt bike, an old 70's model trail bike, a moped, maybe even on a Chinese kids bike, but not on any modern dirt bike. Gas mileage on dirt bikes isn't really something most folks think about but yes, 4 strokes tend to be more fuel efficient since they don't have to be run in the higher RPM range like a 2 stroke, but MPG depends greatly on how hard you ride. Maintenance is always a big topic when talking about 4 stroke versus 2. In general a 2 stroke needs a top end job about twice as often as a 4 stroke in it's same class, say a YZ250 2 stroke compared to a YZ450F 4 stroke for instance. But, the 2 stroke costs about half as much to do this on so it really works out about even as far as cost of ownership. You do have one extra maintenance with a high performance 4 stroke and that's the valves. 2 strokes don't have valves. Basically you just have the valve clearance checked each season and that's not very expensive, you could also do it yourself. So on the performance differences. The 4 strokes will hook up better due to their smoother power delivery and that smooth power delivery also helps you get around the track faster which is why everyone races 4 strokes now. 2 strokes lack the low end torque of a 4 stroke so exiting corners for instance is much faster on a 4 stroke (any pro racer will tell you that races are won or lost in the corners). While you're clutching that 2 stroke trying to keep the revs up and subsequently spinning your tire exiting the corner, the 4 stroke will be hooking up and blowing by the 2 stroke. Also if you don't ride a 2 stroke aggressively enough you will bog it down and foul spark plugs. A lot of folks talk about 4 strokes not being as powerful and that's not really true. Yes a 250 4 stroke raced against 125 2 strokes (back when folks still raced 125's) but the 2 stroke has a power stroke twice as often as a 4 stroke so that's why the 4 stroke needs twice the displacement to be equal. Comparing a 250 4 stroke to a 250 2 stroke in terms of horsepower is an apples to oranges comparison that means nothing. I grew up racing 2 strokes back in the 80's and have a soft spot for them in my heart. If I were riding woods I'd have no issue riding a 2 stroke KTM, but in motocross the 2 stroke is history except for the mini classes. The 4 strokes are the king of the hill in that arena. Even in woods racing all of the tops GNCC guys are on 450F's, not 2 strokes.