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Gearing & Sprockets

Dirt Bike Gear Speed Calculator

Road speed in every gear at a chosen RPM. Enter up to six gearbox ratios the way the service manual lists them.

Inputs
Results
Live

  • Speed in 5th at RPM

    60.6mph

  • Speed in 1st at RPM

    30.6mph

Table
GearRatiomphkm/h
12.1830.649.2
21.7538.161.3
31.454674
41.2553.485.9
51.160.697.6

Formula

mph_gear = (RPM × tire Ø) / (primary × gear × final × 336)

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