DBDirt Bike Finder
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Performance

Dirt Bike Gear Ratio Calculator

Turn gearbox tooth counts (or published ratios) into overall ratio per gear, including primary and sprockets.

Inputs

One gear at a time

Results
Live

  • Overall ratio

    23.5:1

  • Sprocket ratio

    3.769:1

  • Primary × gearbox

    6.235:1

  • Engine revs per wheel rev

    23.5rev

Formula

Overall = primary × gearbox × (rear ÷ front)

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