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The Speed-Bull can not only measure, but also brake the brake pads. You get perfect results within a minute!

The Pro version has a 4-quadrant drive. By reversing the rotation, the Speed-Bull can also operate the front wheels in the correct direction and new brake pads can be braked perfectly in the shortest possible time.

Before doing some physics

According to the recommendations of some manufacturers, the pads should be braked 30 times from 30 km / h (!) to almost zero.

With the formula E = 1/2 x m x v² (m = 115 kg total weight, v = 8.33 m / s) the energy is 3993 joules (Ws)

On the test bench, this energy corresponds to the formula E = P x t

a braking power P of 660 W over the time t of 6 seconds of 3960 Ws = J

What does that mean?

On the Speed-Bull, with a braking power of approx. 660 W, roughly the same braking process can be carried out over a period of 6 seconds as in reality. After a short cooling phase of a few seconds, this can be repeated 29 times.

Finally, the pads should be really hot again to outgassing.

If in reality a 90 kg rider with a 25 kg e-bike does this over a height difference of 50 m, this corresponds to an energy of

E = m x g x h = 115 kg x 9.81 m / s² x 50 m = 56408 kgm² / s² (J)

On the Speed-Bull that would be a braking power of 450 W x 120 seconds at 25 km / h = 54,000 Ws (J)

These values ​​can vary. A braking power of 1000W is not a problem, but you should already put weight on the front wheel …

In moving images it looks like this:

Of course, this video only shows one braking process.

After that you can measure the brake power.

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