Car starter as E- motor?

[professor]

Took the starter apart to see internals. BIG windings on field magnets, brushes made of copper with lots of drag.

 

[safe]

Copper gives something like four times the conductivity compared to carbon brushes. Higher brush pressure translates into higher currents without overheating. (it lowers electrical resistance)

The starter motor is entirely designed around the idea of massive starting torque and nothing else... it's just not right for an ebike.