Headlight problem...

[Anonymous]

Hi guys,

It's a 79 gs750e. Aftermarket exhaust ,K&N pods and an oil cooler are the only apparent mods.

Great bike when it's running. But I'm losing my headlight. Not good. I am not blowing the headlight fuse. My charging system is working fine. Those stator papers are a gem. I've now started looking at the wiring harness. I have completely disassembled and cleaned the switch assembly and found 2 wires that were not fixed correctly. Apparently whoever had this machine before me had to cut a wire and slice a gash in the side of another. He just cut, stripped, twisted and taped (poorly) the first wire and taped the second where he sliced it's insulation. I'm hoping that this fixes it since the remaining portions of the wiring harness seem to be in near pristine condition. The reason I'm posting is in the hope that perhaps someone else has come across this little gremlin and found a way to excorcis him. This is, of course, if my previous repair fails to do the job.

And another question, does anyone else have the separate R/R on their bike? Mines got it and I'm having a devil of a time wondering how to make sure everything is working perfectly. It's charging the battery great but ,silly me, I hate getting stranded on the side of the road. I would love to be certain that everything is working just as it should be.

Thanks in advance gentlemen,

Keep your knees in the wind,

Ron

 

[beby99]

Ron...

A friend of mine had problems with his headlight not always
working...long story/short, turned out to be a bad connection
in the start button switch.

 

[Anonymous]

ah, Maybe I shouldn't be posting at 4am anymore. I mistated my question.

The question isn't why is my headlight going out. The question is why am I blowing my headlight? I have checked, double checked, triple checked (as best I can) the charging circuit and all of it's components. They are working just fine. Yet my headlight is getting blown. The bulb inside the sealed beam is exploded in the last one. I still have it. I can't figure it out and be certain I have found the culprit yet. I'm hoping it was just the cut wire and it's exposed companion. But I'm not blowing fuses, any fuses. The rest of the lights on the bike are in working order. But I'm stumped until I get the bike back together and put yet another headlight in it to see if this one goes.

Any ideas guys?

 

[earlfor]

If you are not blowing fuses and the only problem is the headlight bulb burning out or disintegrating, I can think of only two causes. 1. High vibration level on the headlight shell due to no isolation rubbers between the shell and mount flanges on the forks or high vibration level due to badly needing a carb synch. 2. If using halogen H4 bulbs, they cannot be touched at any time including removal from package or installation. The oil in you fingers will cause them to burn out or fracture and explode. They should be handled with gloves. I usually put my hands inside a plastic baggie when handling them.

Earl

ah, Maybe I shouldn't be posting at 4am anymore. I mistated my question.

The question isn't why is my headlight going out. The question is why am I blowing my headlight? I have checked, double checked, triple checked (as best I can) the charging circuit and all of it's components. They are working just fine. Yet my headlight is getting blown. The bulb inside the sealed beam is exploded in the last one. I still have it. I can't figure it out and be certain I have found the culprit yet. I'm hoping it was just the cut wire and it's exposed companion. But I'm not blowing fuses, any fuses. The rest of the lights on the bike are in working order. But I'm stumped until I get the bike back together and put yet another headlight in it to see if this one goes.

Any ideas guys?

 

[Anonymous]

With the bike running at 2K RPM, what's your voltage at the battery and at the headlight plug?

 

[nert]

Still not sure what you have. IS the filament exploding? that is normally caused by over voltage. (you can over volt with out blowing a fuse. fuse is current protection) If the filament is broken, thats vibration. If the glass is breaking, BAD vibration (i think you would notice) contamination on glass, like oil from fingers, or exposure to water. What have you there?

 

[Anonymous]

hmmm. I am gonna have to give the voltage at the posts from memory. Since I currently am going through the harness looking for shorts, broken wires and the like. I believe that around 2000 the volts were 12.9 or so around 5000 they were around 14ish. The voltage when checked at the poles never ever went above 14.5 volts.

On the topic of vibration isolation rubber. I am certain that there are none there. Where can I get a set at? Or are they unobtanium and you have to make them from something else? Also, the carbs were synced by a friend of mine. And the bike does run smmooooooth.

My headlight assembly is the sealed beam type not H4.

 

[nert]

If you hold the old sealed beam at just the right angle the reflector acts like a magnifing glass and you see the filament "large".(takes a while to get your focus correct) You should be able to see if its broken in one place, or vaporized (over volt). Excuse this next question. Not a 6 volt sealed beam is it?

 

[Anonymous]

Well, this last lightbulb was a halogen sealed beam unit and that bulb inside the bulb is... well... seen better days. It's in about a bazillion pieces inside the sealed unit. Looks like an overvolt by your description.
Anyone else seen this? Earlfor? Has anyone else had an intermittent regulator failure? I need corroborating evidence before I pitch what looks like a perfectly functioning regulator. Nert, your input is great. Please don't feel insulted at my seeking an additional opinion. I, at this point, just don't have the cabbage laying around to toss it every possible determination of the problem. Oh, and no. it's a 12 volt lamp. I made that mistake once and it cost me a few bucks. I won't be making that mistake again. Thank you Nert.

 

[argonsagas]

My first effort would be to file the sealed beam unit in the scrap bin. After tires, the investment in a replaceable bulb halogen unit is the cheapest and best upgrade you make on your bike.

Vibration can easily cause the problem. and even though you said the bike runs smoothly, there will always be vibration, and it CAN cause the problem you complain of.


My suggestion is that you re-check the connections and wiring. Since you are not blowing fuses, and the charging sytem checks out, a possible culprit is a poor connector or broken wire that makes intermittent contact. This can cause electrical surges when the connection breaks and arcs as it is re-established, especially it it flutters, which is likely witht he vibration. The lamp filament is more susceptible to surge damage than fuses.

IF that should be the cause, you need to fix it anyway, because electrical arcs can, and will, lead to other damage.