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Speed to RPM Calculator

One of the features of the Pro-160 / 360 is the ability to measure an RPM and then display this value, convert it to MPH, and to limit the top speed if required. To allow this we need to know a] the drive wheel diameter and b] any gear ratio between the motor and the drive wheel. Once those numbers are known they can be dropped in to a spreadsheet like this speed to RPM calculator.

Wheel speed – rpm calculator
Inputs Calculations
Wheel diameter [inches] 5.75
Circumference 18.06
revs per mile 3507
Wheel RPM at 1mph 58
Motor sprocket teeth 11
Drive shaft teeth 23
Physical gear ratio :1 2.09
Motor RPM at 1mph 122
Max speed required [mph] 8
Motor RPM at required speed 978
Inches in 1 mile 63360

The spreadsheet can be downloaded here.

wheel speed – rpm calculator

The Physical gear ratio and the Motor RPM at required speed numbers can then be entered into the relevant points in the Pro-160 / 360 menu.