I have a 99' Road King FLHRCI that is all stock and i'm kind of baffled about how the rear and front running lights work. With the power on - my Headlight, two driving lights (if I have the switch on), the two front running/turn signal lamps, the two rear running/turn signal lamps and the fender running/break lamp comes on. Always been that way. When I turn a left/right signal on, the corresponding lamp flashes by getting brighter. What I don't understand is the lamp is a one filament lamp. It can only work by getting more amperage to make it brighter. What am I missing?