why do two-stroke and four-stroke engines have such different power outputs?
In: Engineering
A two-stroke produces a power stroke every revolution of the crankshaft. A four-stroke produces a power stroke every other revolulution. For the same displacement and RPM, a two-stroke is making roughly twice the power.
There’s some other effects involved like pumping and incomplete exhaust and valve efficiency that mean it’s not exactly twice, but it’s close.
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