head light always burning out

[808stalion]

ok i went through 2 headlights already when its on idle the headlight works fine but as soon as i rev the motor it burns out what could be one short someplace but where????? what else could be

[Clivester]

Most likely your voltage regulator has gone bad.

Check in the Tech section for a suitable manual. Most of them have directions for testing the regulator/rectifier towards the end.

Please let us know what model and year you have when asking tech questions - it makes troubleshooting easier.

[martynkim]

Some honda models will burn out the headlight with a dead battery being the only issue. (my 77 nc 50 express) my headlight is burned out now. I thought my battery had a charge

[808stalion]

its a 85 spree and my batt is dead and with my tail/brake light i hooked up the wires and still no come on . what is that green wire that look like its coming from inside the frame by the brake lights?

[martynkim]

I dunno what that wire is but my Spree lights work with or without a battery. Run a hot wire and try to power them might have a wiring issue

[fightingplankton]

that green wire toward the back of the frame that goes up inside it...i believe that is your ground.
its got a little T shaped bit of metal at the end that is (or should be) screwed into the frame.

[808stalion]

ya its a ground could not see last night was to dark but i will try and work on it again today i need that bike to goto work tonight

[mousewheels]

The AC headlight output coil has a voltage which varies with engine RPM, idle --> low, full speed --> Too high for the bulb

What keeps the bulb happy is the regulator. When the average voltage rises above its design point, it 'shunts' energy to ground, keeping the average AC voltage safe for the headlight. A bad regulator or missing ground to the regulator can disable this functionality.

We've discussed regulator operation, taken scope photos and instrumented average voltage at the headlight to demonstrate operation of the regulator. http://www.hondaspree.net/phpBB3/viewto ... 501#p92501

[tazland001]

mouse is correct. It is the rectifier. seen it a million times. the current from the stator is to hot that is why they use the rectifier to control the current so it does not spike and burn all your lights out.


Taz