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Aerodynamic Drag Calculator

The calculator gives you some idea of the impact of aerodynamics on your ability to go fast. Roughly a standard PX puts out about 8 HP at the rear wheel which will mean your top speed will be less than 100 Km/hr when you are sitting upright (rolling resistance has not been accounted for). To go faster you are fighting more air hitting you faster, so to go 2 times as fast you need 8 times the power!

If you play about with the reference area, you can simulate the effect of ducking down. For example change 0.88 to 0.70 metres squared and you see you can go 110 km/hr with the same power by ducking down. If you play about with the drag coefficient you can see the effect of make the scooter more stream line, for example adding a screen to reduce the drag of the rider (i.e. same surface area but more aerodynamic).

Aerodynamic Drag Spreadsheet

 Based on the Drag Equation

Spreadsheet removed because it is wrong - calculations have disappeared somehow