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Engine & Maintenance

2-Stroke / 4-Stroke Displacement Calculator

Same swept volume math, plus a power-stroke comparison: a two-stroke fires every crank revolution, a four-stroke every other rev.

Inputs
Results
Live

  • Swept displacement

    249.32cc

  • Cycle

    4-stroke

  • Power pulses / min

    4,000

  • Rough 2-stroke equivalent

    124.66cc

    Rule of thumb only — porting, valve area, and boost change this a lot

Formula

Swept cc as usual · Power pulses / rev = 1 (2T) or 0.5 (4T)

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