I'm hoping someone can help me out with the following circuit. It is a lighting and battery charging circuit of a Honda dirt bike/motorcycle. I'm certain of all the connections, but don't know exactly what is being done inside the regulator/rectifier. I know it is converting AC to DC and regulating the output, but I don't know HOW it is being done. It is my understanding that current only flows through the top half of the coil for the charging circuit and the bottom half for the lighting circuit, but since the battery is grounded to the chassis, I don't see how the charging current cannot flow through the entire coil.