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Gearbox & RPM Calculator

Convertissez le régime moteur en vitesse à travers la boîte et le pont, comparez les rapports et comprenez leur effet.

✔ 100% free Mobile friendly ⚡ No account

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The drivetrain equation

Road speed = engine RPM ÷ (gear ratio × final drive ratio) × wheel circumference. Short ratios give acceleration; tall ratios give lower cruise RPM and better economy.

  • Speed (km/h) = RPM ÷ (r_gear × r_final) × wheel_circumference(m) × 0.06
  • A lower final drive (e.g. 4.10 → 3.73) lowers cruise RPM and fuel use, but slows acceleration
  • RPM drops when shifting up; the calculator shows speed per gear

FAQ

Le rapport est dans la boîte par vitesse ; le pont est la réduction finale. Total = rapport × pont.
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