What does 6mm of can diameter buy me?

[Finnster]

Since we are talking a 3D cylinder rather than a line, I would say you are increasing the rotor mass by (pi*13^2)-(pi*10^2), or +69%. It shouldn't be linear but more exponential.

The torque should also increase as the force vector would move outward. IE, I would take a guess that the power would be more than 30% if everything else was equal.

In real terms, how many more teeth? Hell if I know :D