Re: a quick question
40655 indeed does charge the battery when running. A pair of coils (stator) under the flywheel produce an AC voltage as the flywheel magnets pass by. That AC then goes to the rectifier, an array of four diodes, that changes the AC to DC. When the produced DC voltage exceeds the DC voltage of the battery at the moment, a DC current then flows through the battery backwards, which recharges it.
There is no voltage regulator on that motor, nor on many other models of the era.