Miles / Kilometres per Hour from Motor Speed

IMPERIAL		METRIC
Miles per Hour from Motor Speed		Kilometres per Hour from Motor Speed
Vehicle speed in miles per hour is the rolling radius of loaded driving tyre multiplied by the motor RPM and divided by 168 times the overall gear reduction of the power train. Where: 168 = Factor RPM = Revolutions per minute of the motor r = Rolling radius of loaded driving tyre in inches R = Overall gear reduction including both axle and transmission MPH= Vehicle speed in miles per hour Example: Find the MPH of a vehicle where the motor speed is 1680 RPM, the rolling radius of loaded driving tyre is 15 inches and the overall gear reduction is 10		Vehicle speed in kilometres per hour is the rolling radius of loaded driving tyre multiplied by the motor RPM and divided by 168 times the overall gear reduction of the power train. Where: 2651.51 = Factor RPM = Revolutions per minute of the motor r = Rolling radius of loaded driving tyre in millimetres R = Overall gear reduction including both axle and transmission MPH= Vehicle speed in kilometres per hour Example: Find the KPH of a vehicle where the motor speed is 1362 RPM, the rolling radius of loaded driving tyre is 400 millimetres and the overall gear reduction is 10

IMPERIAL

METRIC

Miles per Hour from Motor Speed

Kilometres per Hour from Motor Speed

Vehicle speed in miles per hour is the rolling radius of loaded driving tyre multiplied by the motor RPM and divided by 168 times the overall gear reduction of the power train.

Where:
168 = Factor
RPM = Revolutions per minute of the motor
r = Rolling radius of loaded driving tyre in inches
R = Overall gear reduction including both axle and transmission
MPH= Vehicle speed in miles per hour

Example:
Find the MPH of a vehicle where the motor speed is 1680 RPM, the rolling radius of loaded driving tyre is 15 inches and the overall gear reduction is 10

Vehicle speed in kilometres per hour is the rolling radius of loaded driving tyre multiplied by the motor RPM and divided by 168 times the overall gear reduction of the power train.

Where:
2651.51 = Factor
RPM = Revolutions per minute of the motor
r = Rolling radius of loaded driving tyre in millimetres
R = Overall gear reduction including both axle and transmission
MPH= Vehicle speed in kilometres per hour

Example:
Find the KPH of a vehicle where the motor speed is 1362 RPM, the rolling radius of loaded driving tyre is 400 millimetres and the overall gear reduction is 10

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