This listing is for a Microsoft Excel based speed calculator for go karts, buggies, mini bikes and more.

Use this speed calculator to determine the ideal sprocket and tire size on your motorized vehicle.

The calculator works with three major drivetrain types as follows:

• CVT torque converters utilizing an intermediate jackshaft
• Centrifugal clutches utilizing an intermediate jackshaft 
• Centrifugal clutches directly driving an axle sprocket

This speed calculator not only determines top speed based on multiple input parameters, but also determines the clutch engagement speed, ideal when designing an off-road vehicle where you want the clutch to be engaged by a certain speed.

------Inputs for each calculator type------

CVT With Jackshaft Inputs:

Engine RPM

Torque Converter Engagement RPM

Clutch Overdrive Ratio

Clutch Reduction Ratio

Jackshaft Sprocket Teeth

Axle Sprocket Teeth

Tire Diameter

Centrifugal Clutch With Jackshaft Inputs:

Engine RPM

Clutch Engagement RPM

Clutch Teeth

Jackshaft Sprocket To Clutch Teeth

Jackshaft Sprocket To Axle Teeth

Axle Sprocket Teeth

Tire Diameter

Centrifugal Clutch Without Jackshaft Inputs:

Engine RPM

Clutch Engagement RPM

Clutch Teeth

Axle Sprocket Teeth

Tire Diameter

The spreadsheet also includes quick reference specs for some common comet torque converters such as the 20 series, 30 series, 40 series and 44 magnum series CVT torque converters.