Overall Electrical Woes

[Guest]

I just got an 81 GS850G a couple months ago and since I've got it I've been fighting with the crappy electrical system full of bullet connectors and plastic plugs that are old and dirty. I cleaned everything out and still had a problem not getting the full 12V to accessories like the lights and ignition coils. Now I've read about adding a relay to each circuit but I think I have found the issue at least on my bike and if I'm right I don't believe the relays are necessary.

Using a voltage meter I measure the voltage drop across each individual connection in the circuit from the battery until I arrived back at the fuse box to go back out to each different circuit. I found a .1v drop across the first bullet connector before I even got to the fuse box, I also found significant voltage drops between the fuse holders and the fuses. I also found a significant drop between the bullet connector going out of the fuse box up to the ignition switch. Surprisingly, I did not find a huge drop at the switch, but I did find a huge drop going from the bullet connector up to the switch. You can also tell when a certain connection has a high resistance because it will be hotter than the wires going to it. By the time I had gotten back to the fuses through two bullet connectors, two fuse holders, and ignition switch, plus a run of wire that went from the battery to the fork and back again, I had lost a full volt!

Now measuring from the orange wires going into the fuses and the voltage at the coil showed no significant voltage drop. This is where I come to my "fix". I am going to try to use one relay that is switched off the red wire to feed the three orange wires. this way I should get a full 12volts to all circuits. I also plan on running the r/r output straight to the battery. Any cons to this?

Please give me some feedback on any thoughts or concerns?

[wymple]

I have the same bike. All my electrics had sh*tty connectors that have been obviously overheated to the point where some were fused too hard to separate. I replaced all that was reasonably possible to keep it functioning, but could only get the charging system to show 12.2-12.3 across the battery, and R/R was too hot to lay a hand on for more than a few seconds. I wired the stator direct and put on dedicated grounds & such, and picked it up to a constant 13.8-14 volts, and the R/R barely gets warm. It has been my best improvement, along with a Dyna S that I wired as a stand alone ignition with it's own switched feed to the coils, after frying a wire on the road. The only trouble since then has been a weak coil, cured, and a stinking deer in my front end at highway speed.

[Cassius086]

I say leave the R/R wired into the harness for the 12V power supply. Wiring directly to the battery greatly increases the amperage load on the fuse block, etc. even when the key is off.

http://www.thegsresources.com/_forum/showthread.php?225446-SH775-positive-wire-wiring-question&highlight=wiring+the+R%2FR

Great post by Posplyr:

http://www.thegsresources.com/_forum/showthread.php?152769-GS-Charging-System-Health&p=1138531#post1138531

Some more good reading on the subject:

http://www.thegsresources.com/_forum/showthread.php?170746-Why-does-Suzuki-split-R-R-output-between-ignition-and-battery&highlight=wiring+the+R%2FR

[OldVet66]

Try cleaning all your switches and grounds, they are notorious trouble spots, be sure to use a clear plastic bag so you don't loose any critical springs or parts when you take switches apart. Use a good contact cleaner and coat everything with dielectric grease when you finish. Hot plugs are a sure sign of high contact resistance (= voltage drop). I'm in the process of gathering all the information I need to replace my plugs with Furukawa sealed connectors. I already have a ceramic plug for the headlight. Generally go over every possible electrical contact point on the bike and run a nice heavy single point ground directly from the battery negative to a R/R bolt or as near as possible and spider out to other parts of the bike so you don't have to depend on any bolted together steel or aluminum parts for a ground except for the starter motor negative that is the motor case.

[81GS850]

Thanks everyone and thanks Cassius for the links! But now I have a different question. I'm going to run the r/r into the harness as usual. But because I'm putting a relay in the orange wire and using the red wire as a switch signal, wouldn't I want to run the r/r into the orange wire? Since the orange wire is where the load is?

[wymple]

"I say leave the R/R wired into the harness for the 12V power supply. Wiring directly to the battery greatly increases the amperage load on the fuse block, etc. even when the key is off."

Yes, my power supply is still switched. I wired the 3 feed wires direct and as short as possible, and beefed up the grounding.

[posplayr]

It is very difficult to convey anything without a schematic. I showed a recommendation on how to wire the Eastern Beaver which uses a Relay.

[Cassius086]

Thanks everyone and thanks Cassius for the links! But now I have a different question. I'm going to run the r/r into the harness as usual. But because I'm putting a relay in the orange wire and using the red wire as a switch signal, wouldn't I want to run the r/r into the orange wire? Since the orange wire is where the load is?

I agree with Jim...a schematic of you proposed set up will help dramatically.

[posplayr]

This shows an example of how to wire in a relay using the Easter Beaver fuse box.

http://www.thegsresources.com/_forum/showthread.php?192259-Please-help-with-Compufire-Eastern-beaver-PC8-Install&p=1637803#post1637803

[81GS850]

Hey guys... Spent some quality time with the bike last night and I used a salt/vinegar solution to clean all the contacts in the bike. My voltage drops came down a lot to what I think is an acceptable level, but I'll have to verify that tonight. It was too late when I finished up and I don't remember the readings I took but I think they were all below .5v drop total.

I did a SPG at the (-) terminal on the battery. Is this acceptable? I have the harness, battery lead that goes to engine case, and <12" 12 gauge wiring from the r/r ground to the batt (-). My R/R is mounted under the battery case and I couldn't see a real good place to mount it.

Talking to one of the guys at work i remembered that there is that single leg loop up into the harness that then comes back to the r/r. Isn't this loop supposed to light the headlight? and if so, does that mean this phase is un-rectified since it doesn't go through the r/r first?

[tom203]

Talking to one of the guys at work i remembered that there is that single leg loop up into the harness that then comes back to the r/r. Isn't this loop supposed to light the headlight? and if so, does that mean this phase is un-rectified since it doesn't go through the r/r first?

On stock setup, one stator leg runs up to headlight switch and then back to r/r. Make sure you eliminate this and wire all 3 stator outputs direct to r/r
probably best to retread this link

http://www.thegsresources.com/_forum/showthread.php?152769-GS-Charging-System-Health&p=1138531#post1138531

[81GS850]

On stock setup, one stator leg runs up to headlight switch and then back to r/r. Make sure you eliminate this and wire all 3 stator outputs direct to r/r
probably best to retread this link
http://www.thegsresources.com/_forum...31#post1138531

Yes I know this, and I have eliminated that, wiring the stator directly to the R/R. The wiring diagram for my bike just shows this wire looping back on itsself then going back to the r/r. basically showing an extended loop. I'm not saying the diagrams right, but if you send unrectified power to the headlight, how will that work out? Aren't you sending one leg that's producing AC voltage to the headlight in the stock configuration?

[Steve]

I am going to try to use one relay that is switched off the red wire to feed the three orange wires. this way I should get a full 12volts to all circuits. I also plan on running the r/r output straight to the battery. Any cons to this?

That is basically what I have done when I have installed an Eastern Beaver fuse box. I have three of our bikes done, the fourth one is in the process right now.

The orange wire switches the relay, which then sends power straight from the battery to the three fuses that power the bike.

I did a SPG at the (-) terminal on the battery. Is this acceptable?

Electrically, it's acceptable. Logistically, it's a nightmare.
How many wires do you want to try to keep track of if you ever have to pull the battery?
Personally, I do my SPG next to the battery, then run a wire to the battery. That way, there is only ONE wire to attach to the battery.

Talking to one of the guys at work i remembered that there is that single leg loop up into the harness that then comes back to the r/r. Isn't this loop supposed to light the headlight? and if so, does that mean this phase is un-rectified since it doesn't go through the r/r first?

That wire does NOT power the headlight.

There are (OK, used to be) two sets of switch terminals in the headlight switch. One of them would switch DC power from the LIGHTS fuse to the lights, the other would switch one leg of the stator. The theory was to remove some excess input that the R/R would otherwise have to try to control when the lights were off.

I'm not saying the diagrams right, but if you send unrectified power to the headlight, how will that work out? Aren't you sending one leg that's producing AC voltage to the headlight in the stock configuration?

See my comment above. The DC current to the light and the AC current from stator to R/R go through two separate sets of terminals in the switch. They just happen to get switched at the same time.

.

[posplayr]

Putting the SPG at the battery is basically undermining the whole principle. You would be just as well to leave it stock.

[81GS850]

Sorry If I'm irritating anyone with these questions.. I get the stator leg up to the switch and makes sense.. Thanks for explaining that.

Can you tell me please why the SPG at the battery is a bad idea? So it's better to have the wiring harness neg, a lead coming from the r/r, and then a lead coming from the battery to be the SPG instead of the battery (-)? I can't get the r/r to be the SPG unless I extended the harness (-) which I thought would be a bad thing?