headlight issue, gy6 150, AC powered  By  cytoruck (Read 13,593 times)

Voltage regulator may be bad . AC lights brighten and dim with RPMs and most tail lights are 5 watts as brake lights are 25 watts . I replaced the rear 1157 bulb with an 1157 LED which uses less power and requires no mods simply insert like a bulb and my twin headlights were a hair brighter .

My other scooter is an Echarm with DC lights that stay the same regardless of RPMs and pretty bright to only be 35 watts . My Magnum has twin 35 watt bulbs and I can see great with them . My old TaoTao was barely above a candle and was very limited to to what I could see at night .

Make sure the battery is charged like with a trickle charger so that the stator can deliver as much power to the headlight(s) rather charge a weak battery , Make sure headlight lens is clean and streak free .

Some have an 8 pole stator , some 11 and my Echarm has 12 poles . More poles more output , Many have upgraded to and 11 pole stator . Check the bulb wattage as you may be able to go up ten watts but nor more . I read where some tried 55watt bulbs and melted the bulb housing as they are hotter than less wattage bulbs .

Now there is also a HID option but is costly and will take an hour or more to install . For me the blueish white hue glares rather than helps visibility with me bad eyes even more so in the rain at night

I have seen auxiliary cornering lights or LEDs which helped put out more lumens . i had a Harley behind me one night who had auxiliary that were so bright I could have driven with my lights off and could see by using his

dont the headlights run directly off of one of the stator wires? why would the voltage regulator make a difference? also, while all the information provided is great im not seeing how the tail lights needing to be changed would effect the headlights? headlight lenses are clean i can physically see the light being created on or in the filament of the bulb and its incredible dim at idle then it gets super bright while riding and then eventually just fades away, im not sure if you guys missed it or maybe i missed the part addressing it but how is it that applying the brakes makes the headlights full bright, almost like the brake lever switches the headlights to dc, like... it instantly goes bright, I am going to try unplugging one headlight and seeing how the operation is and then unplugging the other one, i wouldnt think the voltage regulator would be bad though either simply because the battery is 100 percent charged, it has been running and starting perfectly for weeks

From what I think I know, the R/R does effect the voltage sent to the lights, off of the yellow wire. The white wire effects the battery charge. Two different functions. So the R/R could be bad.

As for the headlights coming on brightly when the brake levers are pulled, it sounds like your headlights could have a bad ground issue. This is what I would look into before replacing anything. Check the bulb sockets for corrosion, loose connections etc.

EDIT: He beat me to it. Also, bad connections create resistance which causes heat. Heat increases the resistance.

What Bike is it.?
Where's the wiring diagram?
The lighting coil feeds power to the yellow wire to the lights and to a shunt regulator.
The coil can produce excessive voltage if not regulated. The regulator shorts out the excessive voltage to ground. A zener diode does the regulating by its reverse bias voltage setting. 12.6 volts. once the zener conducts it turns on a triac (SCR silicon controlled rectifier) that grounds the circuit for that pulse and regulating the output voltage.. This happens on every pulse of power.

If you run with the regulator disconnected you blow out all the lights/tack/whatever is in the circuit. So that's a nono.
You can unplug the stator wires and run test on the coil that way.

In the case where the light go bright the power for this effect is coming from the rear lights and the battery. It's a backfeed.

the bike is split in 2 electrical systems. AC for lighting and DC for battery. When you hit the brakes you are connecting both AC and DC systems togather briefly. That's whats up.

The original issue is too much draw / or a bad ground/or a melted connector somewhere/ a defected (open) diode.
Welcome to the club..
Have a Drink.