Magnet overhang is the excess magnet length beyond the stator stack.
The magnet overhang can be geometrically constructed for the surface mounted motor designs. It is believed to increase flux linkage by the coils and hence increases the torque production. Magnet overhang is also used by rlib to account for the rotor backiron weight, magnet weight and the total motor weight.
Code implementation
Motor.Rotor.MagnetOverhang=5 // sets the magnet overhang on each side to 5mm. This also increases the backiron width to match that of the magnets.