It all has to do with this,
ASK RAPTOR :P
It has to do with where the weight is placed in the design of the wheel (more weight at the center or hub of the wheel, or more to the outside of the wheel), the diameter of the wheel, the weight and diameter of the rotor, etc. Inertia, accelerating forces applied to the wheel and kenetic energy all play a factor. That's a tough answer to put together when you look at all the variables. It would be better to try different wheels or rotors while noting their weight properties and designs and make some data sheets to compile the effects between different designs.
When all else fails,
ASK RAPTOR 
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