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Two strokes can have a fairly broad torque curve, or a very peaky one, depending upon how they are tuned. The usual problem that led to high sides was the fairly abrupt increase in torque as the motor "came on the pipe" which is to say the area of the power band that the expansion chamber in the exhaust starts having a pretty major effect on the amount of fuel/air in the cylinder. It feels somewhat like a turbo coming onto boost, but a two stroke can make a turbo feel lazy. A 500cc two stroke available to mere mortals, like a Honda CR500, will be a single cylinder bike making around 55-60hp. A GP two stroke was usually a 4 cylinder, making 180hp. They made their power at much higher revs than a CR500 and their powerband was quite a bit narrower.
A modern 250 two stroke GP bike is a serious weapon indeed, partly because they do make a lot of power for their weight but also because they are so damn small, you'd be amazed the first time you see one. Their corner speed is stupendous, if you have the talent and the balls to come close to its limits. A 125 is even smaller, looking like a half-size toy. A 250 GP bike can still lap near lap record pace at a typical US track.
JR
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