Soapbox Speed Calculator

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Gradient %
Total Mass kg
Mass of Wheels kg
CdA m2
Air Density Kg/m3
Top Speedmph

Terminal velocity of a gravity racer is the theoretical maximum speed at which the drag forces exactly equal the force due to gravity. It is theoretical because it is an asymptotic limiting value that cannot ever be reached, although you can get very very very close.

The table on the right will allow you to calculate the approximate top speed of a cartie on a given slope, and the distance needed to reach that speed. Just use the "up" and "down" arrows to adjust the parameters and see how the top speed changes.

Because terminal velocity is is never achieved, the figure quoted is the distance needed to reach 99.9% of the terminal velocity.

For a more accurate estimation of speeds on any given course, grab yourself a copy of SCA Cartie Sim.