GL1200 LTD - Electrical gremlin


Information and questions on GL1200 Goldwings (1984-1987)
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doc2bmrd
Posts: 6
Joined: Sat Apr 09, 2016 8:27 am
Location: Wyoming, MN
Motorcycle: 1985 GL1200L Limited Edition

GL1200 LTD - Electrical gremlin

Post by doc2bmrd »



I thought I had my charging problem diagnosed down to a bad voltage regulator. Ordered a new one, hooked it up and it seemed to be charging properly (~13.6V as indicated by the volt meter on the dash). BUT ... it was getting *really* hot. After the bike had been running a few minutes (and the voltage regulator getting especially hot), the voltage dropped to about 11.4 to 11.6V (which is about what it was with the old voltage regulator).

I completely disconnected the new voltage regulator. It appears to have continuity between green & one of the yellows in both directions, which I understand is bad. I'm thinking I fried it somehow (?)

I also discovered something else ... with the 2 R/W wires disconnected from the voltage regulator, it did NOT get hot. I checked those wires and it would seem that there is continuity with ground and the R/W wires that run from the voltage regulator toward the battery. That does not seem right to me for some reason. Should I have continuity with ground on those wires?



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Rednaxs60
Posts: 2353
Joined: Wed Nov 18, 2015 12:44 pm
Location: Victoria, British Columbia, Canada
Motorcycle: 1985 GL1200 LTD
1995 GL1500 SE CDN Edition
2012 Suzuki DL1000 VStrom
2008 GL1800 (sold)
Ontario 1985 GL1200 LTD (sold)

Re: GL1200 LTD - Electrical gremlin

Post by Rednaxs60 »

I have an '85 LTD that I have been refurbishing/rebuilding over the last 16 months. Installed the alt conversion when I had a stator issue.

The RR should not be getting that hot, but it will get hot. You mention that the voltage drops after a few minutes. I would surmise this is at idle and the voltage should drop if the battery is fully charged. The voltage will also drop because of the engine speed.

Here is a schematic of your stator and RR connections:


When I did the alt conversion I also removed the old RR and stator wiring. You will notice on the above schematic that I have circled three joints. The first two closest to the RR are where Honda has joined the green and red/white striped wires together just after these wired enter the wiring harness. The red circle on the right side of the schematic is where Honda has joined the red ignition wire from the starter solenoid to the red/white striped charging wires together in the wiring harness (about midway between the RR and starter relay). I would think this is to channel some of the power directly to the bike when operating as these fuel injected models need a lot of power to operate.

Here is another schematic of the 1200 charging circuit:


This schematic describes how the stator wiring is connected in the RR. One leg is shunted to ground to regulate the voltage to a maximum of 14.4 VDC. This would indicate that one of the yellow wires should have continuity to ground.

With the R/W wires disconnected from the RR there is no current flow and therefore no power going through the RR. There may be some current flow to ground because the stator is still generating power.

I'm still learning and as I delve into topics such as this I learn more.

Hope this helps.

Cheers
"When you write the story of your life, don't let anyone else hold the pen"

Ernest

flash1942
Posts: 149
Joined: Fri Jan 24, 2014 4:37 pm
Location: Midwest
Motorcycle: '84 Aspencade

Re: GL1200 LTD - Electrical gremlin

Post by flash1942 »

There is a lot of great info on this forum. Not knowing all of the info about your problem it sounds like you have a correctly functioning system. (guys step in here if I'm off base) The stator is putting out 100% of it's power 100% of the time and the regulator WILL get hot. Now if it's putting out like I said then it HAS to be putting an additional load on the engine. And seeing that happen tells me that when things run to the limit then they will run hot, which includes the stator windings, which in turn, may cause the winding insulation to break down resulting in a failed stator or associated wiring.
Enter here an easy fix: Buy a Shindigen SERIES type regulator from Roadster cycle.com ( a real stand up guy) and your problems will be gone. A series type makes the stator behave much like an auto charging system and supplies power to the bike only what and when it needs and no more. I have done two bikes that way and am well pleased. Plus it is less expensive than going to Poorboy.
Also one thing to keep in mind is NEVER exceed the wattage of your stator output. Better yet try to stay 50 to 60% below the max output. In other words don't make your bike a rolling Christmas tree. Add your wattage from all the lights and doodads you use.

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Rednaxs60
Posts: 2353
Joined: Wed Nov 18, 2015 12:44 pm
Location: Victoria, British Columbia, Canada
Motorcycle: 1985 GL1200 LTD
1995 GL1500 SE CDN Edition
2012 Suzuki DL1000 VStrom
2008 GL1800 (sold)
Ontario 1985 GL1200 LTD (sold)

Re: GL1200 LTD - Electrical gremlin

Post by Rednaxs60 »

Have tried the Roadster RR - SH847 - on my '85 LTD in place of the Shindigen OEM replacement. As you mention, great piece of kit; however, I did eventually do the alt conversion for approximately $200.00 CDN comparable to the $200.00 USD for the series RR. An issue with the SH847 is the space required to fit the RR on an '85 LTD. I found that it would not fit in the same spot as where Honda has the RR, it is that much larger. You will have to find a place elsewhere and probably closer to the rear of the bike. Still have the unit. Good suggestion to upgrade to the series RR.

Checked the SH847 this morning and found that there is continuity between ground and the red wire of the unit. No continuity between ground and the stator yellow wires.

Cheers
"When you write the story of your life, don't let anyone else hold the pen"

Ernest

doc2bmrd
Posts: 6
Joined: Sat Apr 09, 2016 8:27 am
Location: Wyoming, MN
Motorcycle: 1985 GL1200L Limited Edition

Re: GL1200 LTD - Electrical gremlin

Post by doc2bmrd »

Wow!! Appreciate the info guys. I did do some studying of the wiring diagram in my shop manual and noticed that the R/W is joined with the R ignition wire from the starter relay. That explains why I get continuity in the R/W even when unplugged at both ends.

The aftermarket replacement I tried was an ElectroSport ESR570 ... and it failed after about 5 minutes of run time. Got ~13.6 to ~14.0V until it fried. Was slightly variable with RPM's. After failure, then about 11.6 regardless of RPM's. I take this as the difference between output from 3 yellows (each at ~5.5 to 5.8 V) limited by the voltage regulator ... to 2 yellows, now unregulated with all voltage going out. I assume the other yellow is now dumping all its voltage directly to ground.

On some advice from another message board, I snagged a used OEM off eBay for $25 and am going to give it a try. Will be removing all connectors and soldering all wires at the Rect/Vreg.

If this one fails ... then yeah, will probably go with the unit like the one from Roadster cycle.com. If this were winter, I'd consider the Poorboy, but I want to ride!! Fortunately, at least I've got a V65 Magna for backup.



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