Yes I was going to advise a analog meter(old school) I have both cause a digital meter moves so fast,analog is easier to pickup spikes. You will test the 3 yellow wires coming out of stator for ac voltage. You can also ohm test each leg , ground it to the engine , but that won't show difference in voltage.

Hi All,

I put a brand new bulb in last night after work and I rode off to class, about a 15 minute ride, city driving. This is the second Philips 9003 (they come in a 2-pack). High and low beam working. J_O_G unfortunately the bulb blew before I could test with a good bulb in, but I'll try again once I get a new (higher quality) bulb.

When I turned my bike off, the lights were working. When I turned it back on at night, 4-5 hours later, both high beam and low beam were off. This is different than what happened to the last bulb. Low beam burnt out first, then high beam burnt out the next day.

I am suspicious.. perhaps when I turn the bike off using the handlebar on/off switch, it is sending some voltage spike to the headlamp. What else could be burning the bulb out WHILE the bike is off?

NO OTHER BULB IS HAVING A PROBLEM -- as a matter of fact, I haven't replaced a bulb in 2 years of riding besides this head lamp and an entire turn signal swap after a kid pulled my bike down and snapped it off. There's no flickering, no super bright lamps or anything of the sort.

Dave, thanks for joining the conversation. On the high beam wire, I could produce the 16-19V 25% of the time, and could never produce it on the low beam. Once the bike was hot, I tried and tried to produce the 16-19V spike on the high beam again but I could not. It's probably not the regulator (is regular the same as rectifier?) according to the fact that no other bulbs are burning out.

Ruttly, I saw the analog meter and almost bought it just because it was so cheap. I don't think it will hurt to have one in my tool kit.

Batman/Ruttly, if I have enough daylight after work today I'll get out there and test the ohm/AC on the stator wires. When I do OHM, it is correct that I want to have the bike off right?

Thanks so much!
AJ

It is both a regulator and rectifier....it converts the AC current from the alternator into DC, and it also changes and limits the charging voltage to somewhere around 14 volts.

I really have no idea where the extra voltage would be coming from in a way that only affects the high beam headlght.  There is an orange wire that carries the power from the ignition switch up to the left handlebar elect control.  From there the H/L beam switch sends the power down the white (low beam) wire ....or the yellow (high beam) wire to the headlight.  About half way between the switch and headlight a small yellow wire is spliced into the large yellow wire - and the small yellow wire goes to the high beam indicator light above the speedometer.

So......if the high beam is getting extra power the low beam should be as well - unless somehow the small yellow wire to the indicator light is picking up extra voltage somewhere.  The only place on the bike that can create weird voltage spikes if the regulator/rectifier is working....is the (-) lead to the coil - and I don't know how the yellow wire and the (-) coil wire could be cross communicating.

One wiring thing that does occur fairly common is the wiring harness that goes into the headlight from the left switch - it is bent every time you turn the handlebars - and it is not uncommon for the yellow or white power wire....or the black ground wire to become broken and create a head light power issue - however that creates a "no power" situation rather that "too much" power.

On the '05 model, they changed the starter switch to turn off the headlight when you push the starter button.
Maybe you got so sort of surge/noise going on.
clean the switch.

Protect your tank, spray contact cleaner in it, flick it back and forth.
If you take it apart, sweep up first, and lay a towel down to catch small parts.
Go slow, be careful. There's a spring in there.

Yerwelcome..
I hope that fixes it or at Least changes the symptoms and proves that is where the problem is.