How do headlights work?
How do headlights work?
I know that sounds like a silly question. I've got something weird going on here and I think it may just be a bulb. But, I've got about 6 weeks left on my warranty so before I go dive in, I thought I'd ask. Here's what is happening:
Riding home the other night, I flipped my high beams on. Just about messed my shorts as I got almost nothing! Went back to low beams, all is well. Current status is, with the low beam on, I can see down the road, and my passing lamps are on. Turn on the high beam, passing lamps go out, and I get this "halo" of light that is totally black in the middle.
OK, me thinks, "somehow the headlamp got out of adjustment - need to take a look". I backed the bike up from the garage door, and put a piece of tape on it per the owner's manual dimensions. Low beam: check. High beam: I can't even tell if it is in alignment as I have NO light in the middle of the beam, just this HUGE circle of light about 15" across. Hurmph.
So, if this is as simple as changing the bulb, I'm on it. Just seems really strange. I've done nothing electrical to the bike since I put the GPS mount and XM radio antenna inside the fairing about 20K miles ago when I first got it. No troubles until about a week ago.
Oh yea, 2010 Ultra, stock headlamp.
Thoughts?
Riding home the other night, I flipped my high beams on. Just about messed my shorts as I got almost nothing! Went back to low beams, all is well. Current status is, with the low beam on, I can see down the road, and my passing lamps are on. Turn on the high beam, passing lamps go out, and I get this "halo" of light that is totally black in the middle.
OK, me thinks, "somehow the headlamp got out of adjustment - need to take a look". I backed the bike up from the garage door, and put a piece of tape on it per the owner's manual dimensions. Low beam: check. High beam: I can't even tell if it is in alignment as I have NO light in the middle of the beam, just this HUGE circle of light about 15" across. Hurmph.
So, if this is as simple as changing the bulb, I'm on it. Just seems really strange. I've done nothing electrical to the bike since I put the GPS mount and XM radio antenna inside the fairing about 20K miles ago when I first got it. No troubles until about a week ago.
Oh yea, 2010 Ultra, stock headlamp.
Thoughts?
Extreme HDF Member
Joined: Sep 2010
Posts: 14,744
Likes: 402
From: Phoenix '53, '88, '09 Big Twins
the "high beam" and the "Low beam" have separate filaments, it's like 2 bulbs in the same housing.
they can burn out independently.
the position of each filament in relation to the reflector is also important, if a filament gets shifted "out of focus" it may produce light, but in a position where the reflector cannot project the light forward in a focused beam.
many riders rewire so that he spot lights stay on with the high beam, and H-D now sells a kit if you hate $30 and want it out of your wallet.
many States allow high beam in the daytime, which i use.
it evens out the wear between the low and high beam filaments ( maybe)
the bulb is easily replaced, you may want to look at the sylvania silverstar at your local auto parts store
mike
they can burn out independently.
the position of each filament in relation to the reflector is also important, if a filament gets shifted "out of focus" it may produce light, but in a position where the reflector cannot project the light forward in a focused beam.
many riders rewire so that he spot lights stay on with the high beam, and H-D now sells a kit if you hate $30 and want it out of your wallet.
many States allow high beam in the daytime, which i use.
it evens out the wear between the low and high beam filaments ( maybe)
the bulb is easily replaced, you may want to look at the sylvania silverstar at your local auto parts store
mike
Thanks guys
Yea, the simplest solution is usually best. What's weird is, I've had headlamp bulbs fail before, but not like this. It has been my experience that when one fails, that perticular mode (high/low) goes out completely. Never had one act like this and put a big black spot in the middle of the beam like that.
I'll run out at lunch and grab a bulb from NAPA.
Yea, the simplest solution is usually best. What's weird is, I've had headlamp bulbs fail before, but not like this. It has been my experience that when one fails, that perticular mode (high/low) goes out completely. Never had one act like this and put a big black spot in the middle of the beam like that.
I'll run out at lunch and grab a bulb from NAPA.
Yup - bulb
I actually had bought a 2-pack of Silverstars last time I got headlamp bulbs so I didn't even need to go fetch one.
Really weird though, never saw one "go sideways" like that. Usually a bad bulb is a bad bulb - pretty binary.
I actually had bought a 2-pack of Silverstars last time I got headlamp bulbs so I didn't even need to go fetch one.
Really weird though, never saw one "go sideways" like that. Usually a bad bulb is a bad bulb - pretty binary.
Outstanding HDF Member
Joined: Jul 2010
Posts: 2,727
Likes: 6
How do headlights work?
How do headlights work?
There is a troll in the housing that holds a candle, sometimes a lot of them. The more candle power the better, you know how it is.
There is a troll in the housing that holds a candle, sometimes a lot of them. The more candle power the better, you know how it is.
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Except in the really old bikes, like on the Flintstones. They had a goofy lookin' bird holding the candles.
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Yea, that's on the "someday list". My Road King has LED turn signals and tail light. Really, really bright. Probably do all of them - headlight, tail light, passing lamps, and turn signals. before my ride to Milwaukee next year.
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