Power is the Watts rating of the motor.
Rider and Cargo Weight is the total weight of the the rider(s) and cargo.
Vehicle Weight is the weight of the vehicle with no rider or cargo on it.
Grade is the percent of incline for the calculation.
Headwind is the speed of the wind blowing towards the front of the vehicle.
Motor Efficiency is the efficiency of the motor. Brushed motor have around 75-80% efficiency and brushless motors have around 85-90% efficiency.
Speed is the top speed of the calculation.
This calculator provides an estimate of what size electric motor is necessary
to propel a vehicle on
flat ground or up an incline at a certain speed. It estimates for normal
electric scooter, bike, and go-kart rolling resistance
so if rolling resistance is above normal due to tires with low air pressure or
sand or mud then reduce the motor efficiency percent to account for that. It calculates the user
inputs with gravity, rolling resistance, chain or belt drivetrain efficiency, and air resistance
to obtain the speed result.
This calculator can be used to estimate the motor size and gear ratio when
building or modifying electric scooters, bikes, go-karts, and other types of
Electric motors produce a high amount of torque under load so for example
an electric scooter, bike, or go kart with a 500 Watt motor and one rider could be geared to
go 20 MPH on flat ground and with the same gearing it would be able
to go up a 7% Grade at 10 MPH.
Keep in mind that if a zero percent grade is entered and the vehicle is geared for the calculator's Speed result then the vehicle should only be used on flat ground.