Right, science!
Right, ya 'orrible lot, pay attention!
As we can see, on the left (sloooowww!) is blue, in the 450nm range, with silver just next to it. Then green (although thankfully, not many Fazers are that colour!!). At about 600nm, we have yellow. But when we get to 675 - 750nm, then we get red, and faster. However, off the right of red, off the scale, we have black. Therefore faster!
Black being faster can also be proved by Doppler. Light coloured bikes have a higher refractive index, therefore reflect more. By reflecting, you detract from your total energy. However, darker colours absorb engery, thus increasing the total energy of the system. Black is the most absorbant.
Energy = power, and power = speed.
Therefore, as black bikes have the most energy, they have the highest speed. QED
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