its not a matter of running 6 or 12 or 4v. yea you can run dual voltages if the led has a driver. (a driver is a voltage regulator.) leds last forever when run dc. dc means you need a cap. pulasting dc will blow led's too. simple theory e=ixr. as long as e is regulated properly than current is regulated.
there is an elecronic part that does not pass dc, it stores it like a battery. it also allows ac to short out to ground. ac passes through this device. its called a cap and you need one with led projects. always use the largest cap for cheap. size matters.
practical application of theory means a 12v led does not need a driver with a 12v regulator. a 6v led does not need a driver when the regulator is 6v. the cheapo bulbs last for years.
some led's come with internal driver electronics. these bulbs are expensive and the electronics usually suck because they are designed for e bikes that have a battery and not a magnito. this type of bulb is to be avoided.
since I studied ee I can do things dillon can't do. the 3aaa battery led projector works. its sick how little I spend on 3 aaa projects. all the 3aaa crap has a blinky board. click once twice or three times to toggle between blinky modes the board has no function for a moped and the electronics and will fry quickly. the solution is simple. bypass the blinky board by cutting the wires from the board to the led. then just use the led wires. found this one on ebay for 2 bucks. the 4v drver is a voltage regulator that previously had no moped function. the emitter follower regulator uses as much power as it regulates. no worry with low current led's. found this beauty by doing the ebay search "800lm headlight aaa" 2 bucks! this search worked too "1000LM 3Mode Q5 LED Zoomable Headlamp AAA Head Torch Protable Headlight"
blinky board cut out and testing for polarity.
projector attached to a bracket attached to the horn mount. bend bracket to adjust beam.
dramatic night pic