Originally Posted by bradford
The physical size of the rotors and calipers has little to do with "how much" braking is done by that particular set of brakes. Piston size determines brake bias. And I'm pretty sure that the engineers at BMW understand how to compute optimum bias.
The rear brakes do not do little braking because they're small. They're small because they do little braking.
Hehe, have you owned a car with the same sized brakes on all 4 corners? We do.