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Dirt Bike Final Drive Ratio Calculator

Final drive is rear sprocket teeth divided by countershaft (front) sprocket teeth. This is the ratio you change with a sprocket swap.

Inputs
Results
Live

  • Final drive ratio

    3.846:1

  • Mechanical advantage vs 1:1

    284.6%

  • Stock ratio

    3.692:1

  • Change vs stock

    4.17%

    Shorter / more acceleration

Formula

Final drive = rear teeth ÷ front teeth

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