Gearing / RPM / MPH Calculator
The gear ratio and speed/RPM info for the different drive sprocket options available are below.
Remember there are variations in tyre sizes and wear will also affect actual readings so this is a guide only.
You can enter your own sprocket and tyre sizes to check the effect on gearing.
Remember there are variations in tyre sizes and wear will also affect actual readings so this is a guide only.
You can enter your own sprocket and tyre sizes to check the effect on gearing.
Wheel revolutions per minute
RPM / Primary Drive Ratio * Gear Ratio / Final Drive Ratio
US Tire Circumference (inches)
( Width / 25.4 * Aspect Ratio / 100 + Rim Size / 2 ) * 2 * PI
Speed in MPH
Wheel Revolutions per minute * Tire Circumference * 60 / 63360
Notes
1 - The error NaN means Not a Number. Basically an invalid result, re enter the values & recalculate.
2 - The early F650GS manual rounded gearing values to 2 decimal places so the figures look different.
2 - The early F650GS manual rounded gearing values to 2 decimal places so the figures look different.
Terra
1 - The Husqvarna Terra gear ratio's are the same and the calculator is correct for the ABS model.
2 - The non ABS Terra has an 18" wheel, manually enter the wheel/tyre size and the calculator is correct.
2 - The non ABS Terra has an 18" wheel, manually enter the wheel/tyre size and the calculator is correct.