Headlight troubles..

[sam6942]

Kay... So, I have a headlight that isn't getting enough power. It comes on after the bike is running (like it's supposed to, I assume?), but looks like the battery is dead (battery is good, everything else is fine.) Switching from low to hi beam is slow and still looks very dim. Any ideas?

[natemoen]

I would say pull the headlight and measure voltage at the plug and then start working your way back to the battery cleaning connectors and filling the connectors with dielectric grease to protect them in the future. Then recheck the voltage after you have done that.

Voltage loss from dirty/corroded connectors can rob HUGE amounts of volts from the line.

[sam6942]

How tricky is it to get the fairing off/on? It's kinda cramped in there and I don't want to find out the hard way. I also wasn't sure if it was a component or not, I just had to clean out the starter switch on my other bike to get the headlight to come on. Different issue, but maybe the same kind of thing?

[natemoen]

SHOULDN'T be to hard. Unplug the wiring harness, unbolt the bolts and it should lift right off. Might be helpful to have a second person to lift it of but not necessary.

While your at it might as well clean and grease every connector you find as you go. It is a common problem that the plugs get corroded and full of dirt (especially after 30 years) and need to be cleaned. Its usually something pretty much everyone ends up doing sooner or later, and sooner is usually better.

[DiverRay]

CHECK AND CLEAN THE GROUNDS!! IF you have a fairing, you probably have ALL the voltage going through ONE SMALL ground wire. I drilled a small hole in the bottom rear of the compartment, and ran a second ground wire from the headlight ground to one of the mount bolts on the fairing. That seemed to solve most of the problems I had.
You STILL should clean all the connectors, and clean all the ground points of the wire harness. I used anti-seize on all the ground connections, as it is conductive, and will keep the connections clean for at least a year. DO NOT use it in place of dielectric grease, as it will cause shorts on the power side.

[sam6942]

I did notice everything going through one teensy weensy ground wire, I'll try running a separate one, thanks!

[natemoen]

The thought of the grounds even went through my head, why didnt it come out my fingers....

[cywelchjr]

The grounds are likely, I would also ask if the headlight indicator is on? If it is, the RLU is thinking the headlight is burned out (which it might if the grounds are bad and restricting current flow) and that will cause a slow switch between high and low beam (these things switch a bit slow anyways).

[sam6942]

BAHAHA!! Turns out the PO had a 24V bulb in the headlight . Replaced and FIXED . I did also redo the web of ground wires in the fairing and add a dedicated one for the headlight, though. Thanks, guys!

[natemoen]

That will certainly cause a dim light!

[DAVINCI]

Didn't know there was any such thing as a 24v headlamp

[cywelchjr]

It would be made for something like a diesel of the like that runs a 24 volt system (like a truck maybe?)

[crazy steve]

The military is the only one who uses 24V lighting that I'm aware of... was the PO a GI? Probably 'borrowed' off a Humvee....

[natemoen]

It would be made for something like a diesel of the like that runs a 24 volt system (like a truck maybe?)

Still a 12 volt system, they just have more batteries to supply more juice (mainly for startup).