Headlight issues

[Guest]

Hey everyone, been a while since I was on here....in fact my old account got deleted. Anyway, the headlight on my GS850G is giving me issues. It was going in and out the last time I had the bike running so today I decided to do some investigating. First I turned my key on and the headlight came on. I tried tapping on the light, switching from high to low, wiggling wires, nothing would make the light go out. OK, wierd. So I started the bike. Instantly starting having problems with the light going on and off, I'd tap the bucket and it would go in and out. Then it went out and wouldn't come back on at all. So thinking it had something to do with it heating up I waited and tried again but nothing.

Well, I figured at this point I should get the multimeter out and see what's going on. My bike has the harness that the bulb plugs into with 3 blades. 1 for ground, 1 for low and 1 for high (I believe). So with the key on bike off, I get about 10.5V on both the high and low beam side until I put the high beam switch on.....then the voltage drops right off to almost nothing. With the bike running I get close to 12v but have the same situation where both sides read voltage until I switch the high beam on, then the voltage drops to almost nothing.

So what am I looking at here? Any help is appreciated

[posplayr]

Since the Multi meter is out, do the Quick Test. Sounds like you have a charging problems.

[bwringer]

Agreed -- check for charging problems.

But it also sounds like you need to check and clean EVERYTHING. All the connectors. Everywhere on the bike. Don't skip anything.

Pay special attention to the fusebox. You don't mention what year your bike is, but the fusebox is a very common source of issues like this.

Look for corrosion and signs of overheating.

[GSinNH]

Since the Multi meter is out, do the Quick Test. Sounds like you have a charging problems.

You know, I had done that last summer and it checked out ok, but I just remembered that the battery in the bike is the wrong one. Perhaps the battery is weak and causing me issues. Will check it out if it ever stops raining!

Also sounds like I need to do some cleaning.

[kdo58]

this works really well and does not cost that much, i have tried ebay kits and the cheap ones do not last

http://www.ddmtuning.com/Products/DDM-HID-Kit-Slim-Ballast-35W-or-55W

https://www.youtube.com/watch?v=A2nzhvIXP0g

[JTGS850GL]

this works really well and does not cost that much, i have tried ebay kits and the cheap ones do not last

http://www.ddmtuning.com/Products/DDM-HID-Kit-Slim-Ballast-35W-or-55W

https://www.youtube.com/watch?v=A2nzhvIXP0g

Unfortunately that kit will do nothing for him until he gets his charging system and wiring working correctly.

One think I've found is that the fuse holders and the large gang connectors under the gas tank tend to corrode and melt over time. That's where I would start after checking the charging system.

[GSinNH]

Had a little time and some decent weather to get into things today. First thing I found was that the 10 amp glass fuse for the headlight was in rough shape. One end pulled right off when I took the fuse out. So I replaced that and tried the light. It worked again at first but after starting the bike and letting it run a second it started to fade down and then get bright if I revved the bike up. So now I'm going through and cleaning up as many contacts as I can. I'd also like to get the right battery for it, the one I have that came with the bike when I bought it is too small. Anyone know which everstart batter fits a 1980 GS850G ??

[eil]

I'd also like to get the right battery for it, the one I have that came with the bike when I bought it is too small. Anyone know which everstart batter fits a 1980 GS850G ??

Whatever cross-references to YB14L-A2.

If Everstart is the Walmart brand, be aware that it's going to cost somewhere around $50 and you'll have to replace it again in 2-3 years.

If you can't wait for a battery to be shipped, go around to your local battery store and ask them how much an AGM battery for your bike costs. Should be somewhere around $80. If you can wait a week or so, get this AGM battery for under $60: http://www.amazon.com/dp/B005G55TR8/

[GSinNH]

Worked on cleaning up connections today. Cleaned with contact cleaner, sanded with fine grit where I could and reassembled with dielectric grease. I also took apart the headlight switch to clean up all the contacts in there, they were pretty corroded. Unfortunetly, all my farting around previously had drained the battery pretty good so now I have it on the charger. Hoping that takes care of it. Will also do the quick test again, had done so last summer and it checked out, but things change.

[GSinNH]

Beginning to wonder if I'll get to ride this summer, between work, the weather, and issues. Anyway, I did the quick test and here are my results.

First I put my battery on the charger for a day.

key off = 12.59v
key on = 11.68v
idle = 12.95v
2500 rpm = 13.05v
5000 rpm = 13.1v
key off = 12.90v

My headlight worked at first but then went away shortly after starting. it tried to come back on at 5000 rpm but never really came back on at all. So I think I have some charging issues here. need to investigate further, just have to figure out where to start.

[posplayr]

Obviously your numbers are low. It is probably not the R/r . So the question is if it is your stator. I assume you don't have a clamp on amp meter so the next best think is to do the phase a tests in the stator pages to see if you are dropping voltage . That will indicate charging current and bad connections. If no voltage drop and low voltages the stator is likely fried.

[GSinNH]

Ok, so just went through Phase A on the stator papers, actually had your updated version printed out already. Looks like I need to test or just replace my stator. Positive voltage drop is .20 and negative was .17 so I don't see that as an issue.


UPDATE - Went through Phase B on the chart in the Stator papers and when I got to checking the AC voltage output of the stator between the 3 legs 2 of them were around 45 volts and one was only giving me 2.5 volts.

Looks like I need to change out the stator. I have a spare one in my parts bike which I'll try first because I have no money :-) If that doesn't work looks like i'll be looking to upgrade/replace the stock stator.

[posplayr]

Ok, so just went through Phase A on the stator papers, actually had your updated version printed out already. Looks like I need to test or just replace my stator. Positive voltage drop is .20 and negative was .17 so I don't see that as an issue.

Well your total drops are 0.37V=0.20+0.17 which makes your voltages

2500 rpm = 13.05+0.37=13.42v
5000 rpm = 13.1v+0.37=13.47v (should be >14.25v)

That is still marginal as in the charging voltages should be well over 14V and the only thing left really is the stator. You could do the Phase B tests and mainly jump to the leg to leg and look for imbalance and then the leg to ground to see if you pick up any voltage indicating a short to ground. Regardless of the outcome you are probably looking at a stator replacement.

Do you have an AC clamp on meter? I don't have one (I have an expensive one nobody else will have that hooks to my scope)and despite being dirt cheap my bike is not together at the moment.

http://www.harborfreight.com/clamp-on-digital-multimeter-95683.html

You would use the AC amps setting and just clamp the meter aroudn easch stator wire. Raise RPM to 2500 or 5000 and look for balance in the readings on each leg. I have suspected this would work. Tom did the same to verify the functionality of the Series SH-775 v.s. a Shunt. It is an uncalibrated measurement but you are looking for balance so the lack of a calibrated measurement will not be an issue. That would be he most conclusive thing to confirm the stator is on the way out.

I have meant to post this as an option to Phase B testing but no way to test and confirm it works at the moment. You want to be a guinea pig? HF has a 25% off 4th of JUly sale today as well.

[posplayr]

UPDATE - Went through Phase B on the chart in the Stator papers and when I got to checking the AC voltage output of the stator between the 3 legs 2 of them were around 45 volts and one was only giving me 2.5 volts.

Looks like I need to change out the stator. I have a spare one in my parts bike which I'll try first because I have no money :-) If that doesn't work looks like i'll be looking to upgrade/replace the stock stator.

I started to post before your update. Yep seems so. Any chance you can swing one of those HF meters? You could test it on a known bad stator and it would be a big leap forward in terms of stator testing which up till now has been very problematic. The current clamp could provide be absolute in service evidence of a failing insulation and would be head and solders above all the other indirect measurements.

[GSinNH]

Ya maybe I'll try and pick up that clamp on meter, might come in handy for my job anyway (I'm an alarm technician).