Engine RPM at speed calculator

What RPM will my engine run at speed?

Your engine RPM at a steady speed depends on tyre size and gearing: the wheel turns a fixed number of times per kilometre, and the final-drive ratio multiplies that into engine revolutions. In top gear (1:1), RPM = speed × wheel revs per km × axle ratio ÷ 60. Taller tyres or a numerically lower axle ratio drop cruising RPM.