Here the functionality of the Speed-Bull roller dynamometer for pedelecs is explained in detail step by step.
If you step on the pedals on an e-bike with constant power (pedal power), a certain amount of power is transferred to the ground on the rear wheel. On the road, the e-bike gets faster or slower, depending on its performance. The Speed-Bull measures this performance. As soon as the support of the e-bike is activated or deactivated, a big difference is immediately visible. That difference is vehicle performance.
However, if a performance diagram or the maximum speed is to be measured, this procedure must take place over a certain speed range. This can be chosen freely.
So that the driver can read his own pedaling power on the display, the Speed-Bull must first determine the power loss due to rolling resistance. This depends on the tire pressure, total weight, tire profile and a number of other factors.
The Speed-Bull can actively drive and carry out all necessary measurements automatically.
The exact process is explained in the tutorial 3 Ramps.