a four stroke usually has better oiling system and turns less rpm making same hp. Two strokes are lighter,less moving parts and that equals less unsprung weight. A much simpler design also. Since four strokes dont burn their oil as part of the lubrication and fuel mixture they are more "envirometnally friendly". But if you dont have good valve seal,valve stem guides, and rings then u will smoke like a two stroker. Both have the bennifits and draw backs. Just depends on you style of riding and what your looking for.
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