Btw, I'm not sure if it's a good idea to "rewire" your bike to an SPG layout if you can't get the regular circuit layout (as per the manual) to work...I generally follow the principle of "stock first, mod later".
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Originally posted by exzachtly1 View Post
Btw, I'm not sure if it's a good idea to "rewire" your bike to an SPG layout if you can't get the regular circuit layout (as per the manual) to work...I generally follow the principle of "stock first, mod later".#1: 1979 GS 550 EC "Red" – Very first Bike / Overhaul thread New here? ☛ Read the Top 10 Newbie mistakes thread
#2: 1978 GS 550 EC "Blue" – Can't make it a donor / "Rebuild" thread Manuals (and much more): See Cliff's homepage here
#3: 2014 Moto Guzzi V7 II Racer – One needs a runner while wrenching
#4: 1980 Moto Guzzi V65C – Something to chill
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exzachtly1
Originally posted by roeme View PostTry accessing the forum through "https://" or plain "http://". Its one of the many warts of this here site.
Btw, I'm not sure if it's a good idea to "rewire" your bike to an SPG layout if you can't get the regular circuit layout (as per the manual) to work...I generally follow the principle of "stock first, mod later".
And re: the rewire, yes, I agree with you. I would like to try to make it work in the stock setup if I can figure it out, then rewire. I want to fully understand it. Problem is I think the PO already modified it from stock so I have some work to do to figure out exactly what they changed first... I think posting a video later for you guys to see will help. I have got to be missing something stupid.
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As I mentioned grounding was never a strong suite with the GS engineers which over the years has continued to exacerbate electrical problems. Even a perfect stock configuration is a problem waiting to happen, but then I'm simply repeating myself.
2 of 4 of the wires in SPG is typical stock configuration (#1 B/W ring lug and #2 R/R(-) as I recall this is your extended wire ). The #3 wire bat(-) has been an accepted modification here at GSR for going on 15 years (I did not invent it), and finally the ground is a belt and braces to capture all #4 ground return paths.
Without #1 and #2 you bike will not charge so the stock bike has to have the same.
Without #3 and typical corrosion the bikes are known to undercharge.
Without #4 you will most probably not notice the difference except is certain situations where you are using frame ground to return current to the R/R(-) (e.g. Dyna S or horns).
The SPG as described in my link simply puts you in the best position possible for continued charging performance in the presence of inevitable corrosion.
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exzachtly1
Originally posted by posplayr View PostAs I mentioned grounding was never a strong suite with the GS engineers which over the years has continued to exacerbate electrical problems. Even a perfect stock configuration is a problem waiting to happen, but then I'm simply repeating myself.
2 of 4 of the wires in SPG is typical stock configuration (#1 B/W ring lug and #2 R/R(-) as I recall this is your extended wire ). The #3 wire bat(-) has been an accepted modification here at GSR for going on 15 years (I did not invent it), and finally the ground is a belt and braces to capture all #4 ground return paths.
Without #1 and #2 you bike will not charge so the stock bike has to have the same.
Without #3 and typical corrosion the bikes are known to undercharge.
Without #4 you will most probably not notice the difference except is certain situations where you are using frame ground to return current to the R/R(-) (e.g. Dyna S or horns).
The SPG as described in my link simply puts you in the best position possible for continued charging performance in the presence of inevitable corrosion.
Because I am new to all of this I get tripped up on terminology too so forgive me if I get something wrong... a few things I am currently tripped up on:
1. When you say "solenoid" do you mean the starter relay, attached to the right side of the battery box on my bike?
2. You also mentioned "metal side cover" in relation to the solenoid - "metal side cover (under solenoid mounting bolt) " - I'm not sure where you mean
I'm going to go back through everything now that I can see your photos and in the meantime here's the video:
https://photos.app.goo.gl/G6rKegHuo8Gh3wS88
Let me know if there is anything else I can show and... keep in mind I recorded this before I could see your picturesLast edited by Guest; 07-09-2020, 06:46 PM.
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The main pictures that are the subject of this thread are in one of my albums hosted on GSR.
https://www.thegsresources.com/_forum/album.php?albumid=1998
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exzachtly1
Progress... I moved all the grounds to the point at the bottom of the battery box for now. I have power to everything now, and slightly higher voltage at the instrument cluster bulb (~10v now vs ~7v before)... and it seems like things are a little brighter.
That rear harness ground was definitely at fault, I think. That was the one thing I really changed just now. And it would make sense as to why "wiggling" the battery previously would have an effect.
The only thing is that she won't crank now. Starter button does nothing... still have to go get that battery tested (after work tomorrow). Back to the wiring diagrams I guess and then when I figure out why it wont crank... relocate everything to the recommended SPG setup. Feeling a little better now
Edit: It does crank if I jump the old (now disconnected) piece of ground wire coming off the starter relay mounting bolt to the negative terminal on the battery. I guess that still needs to be grounded... but why does that work, when the old setup did not? A little confused but it seems if I run a new length of ground wire from the starter solenoid to the common ground point I should be good. It's getting dark so I will try this tomorrow I think. To clarify exactly what I did... on the back of the bike I only see one ground coming out of the harness.... this was going to the starter relay mounting bolt via a bullet connector (as seen in video). I simply disconnected that, and ran a new length from the harness to the common ground point. This gave me my lights back but no crank. The ground wire that's now just hanging there seems to be required for the starter relay. Like I said... back to the diagrams but mostly just placing my notes here for future reference.
Edit 2: What I think I did...
Not sure how that ground could be bad. I'll need to look at it closer, maybe pull the battery box. But right now I'm sure I can make things work if I just run one more ground wire from the starter relay wire to the common ground point... Just confused because I don't see this mentioned in the notes about the SPG setup. Am I missing a ground somewhere on this side of the bike? Should there be another one coming out of the harness somewhere? posplayer's link says:
#4: Connects to the (B/W) harness negative ring lugs (typically the one attached at the solenoid mounting bolt). You can leave the other harness ground ring lug (B/W) where it normally is picking up the battery box ground.
I only have one... at least that I've found so far :/Last edited by Guest; 07-09-2020, 09:47 PM.
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exzachtly1
Question - is the starter relay supposed to ground directly through the battery box via the bolt it's connected to? There is no additional ground wire here, right?
And then the lead from the harness that ties into it is supposed to use that same ground?
If so - then is my assessment that the bottom red circle is a "dead" ground for some reason? Battery box not making good contact to the frame or something? I will have to really poke at that and test it with my multimeter but I just want to make sure I have an accurate understanding about how the starter relay is supposed to ground!
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THIS? is your main ground cable to the battery? (two skinny B/W wires) NO! it's supposed to be a heavy cable connected to an engine bolt to handle the starting motor. I'm suprised it doesn't catch fire.... Likewise, your positive cable looks to be light gauge, if the red wire with an eye shown
ground cable-Screenshot_2020-07-10 Video .jpg
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The coloured diagram is...not so clear as the one from the shop manual...which (in my manual anyways) has other diagrams for routing that show connections too..as in, the starting relay grounding to battery box....
650G routing.jpg
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exzachtly1
Originally posted by Gorminrider View PostTHIS? is your main ground cable to the battery? (two skinny B/W wires) NO! it's supposed to be a heavy cable connected to an engine bolt to handle the starting motor. I'm suprised it doesn't catch fire.... Likewise, your positive cable looks to be light gauge, if the red wire with an eye shown
And re: the red wire from the fuse box - that is a new wire but I used the same gauge that was on there. 16 AWG I believe. Should it be thicker? The wire it is connecting to going into the fuse box looks like it might be a little heavier, maybe 14 AWG.
Originally posted by Gorminrider View PostThe coloured diagram is...not so clear as the one from the shop manual...which (in my manual anyways) has other diagrams for routing that show connections too..as in, the starting relay grounding to battery box....
[ATTACH=CONFIG]61345[/ATTACH]Last edited by Guest; 07-10-2020, 01:21 PM.
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I was wondering! it's such a heavy lug for those wires and looks to be for a battery connection....
The "wiggling around the battery that fixes everything" has to be a big clue as to area....it's going to be "obvious" when you finally spot the gremlin, I bet. But meanwhile,
You can of course easily take the solenoid off and bench test it, just to be sure it's working...yellow/green stripe is the relay's +....
CLICK CLICK hopefully.
usually I just say to touch the connection of the Y/G wire on the solenoid to the battery + terminal while on the bike (big red wire coming from the battery to the solenoid) which normally would engage a working starter on a bike safely in Neutral..(gas fumes ignited by sparks permitting) even with the key off, because the wiring and handlebar button and sometimes the key switch can be problematic... but in your case, I'd say take it off and test it away from the funky wires, whichever one it is...you might even have a burned out relay coil in the solenoid?
There shouldn't be any problem grounding as shown to the battery box if it's securely attached to the frame...metal to metal via a bolt,weld,et-al. There's plenty of electrons there that'll be happy to go for a ride ...
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exzachtly1
Originally posted by Gorminrider View PostI was wondering! it's such a heavy lug for those wires and looks to be for a battery connection....
The "wiggling around the battery that fixes everything" has to be a big clue as to area....it's going to be "obvious" when you finally spot the gremlin, I bet. But meanwhile,
You can of course easily take the solenoid off and bench test it, just to be sure it's working...yellow/green stripe is the relay's +....
CLICK CLICK hopefully.
usually I just say to touch the connection of the Y/G wire on the solenoid to the battery + terminal while on the bike (big red wire coming from the battery to the solenoid) which normally would engage a working starter on a bike safely in Neutral..(gas fumes ignited by sparks permitting) even with the key off, because the wiring and handlebar button and sometimes the key switch can be problematic... but in your case, I'd say take it off and test it away from the funky wires, whichever one it is...you might even have a burned out relay coil in the solenoid?
There shouldn't be any problem grounding as shown to the battery box if it's securely attached to the frame...metal to metal via a bolt,weld,et-al. There's plenty of electrons there that'll be happy to go for a ride ...
OK so -- I could not for the life of me figure out why that ground was not working. Tested both points (upper and lower) with the multimeter and there is no ground at those points. There is, however, ground at the bolt just below the relay, on the front of the battery cage - it kinda angles forward. Tested as a perfect ground. So I ran a small wire from the old wire at the top of the relay (where the harness ground used to connect) to that point... and voila she starts! I really wish I knew for sure why the ground specified in the manual doesn't work though. Possible I just don't understand it... idk. If anyone has a picture of what theirs looks like that might help!
I'm even happier to report:
1. I have enough voltage at the instrument cluster for an LED bulb now... so my high beam indicator is restored
2. Re running the simple test, all my numbers are bang-on. 5000 RPM test was sitting at a rock solid 14.5v
3. The friggin horn works, but only while revving above 2500 RPM or so... that hasn't really ever happened
So... next steps I guess is to move the grounds to the recommended place for the SPG setup (right now they are at the bottom of the battery cage), complete the setup by running the #4 ground strap mentioned earlier, do some more cleaning. And then I really want to figure out the horn. I want that sucker to blow while the bike is just sitting.
Is a horn relay the best option for that?
Overall... right now I feel a LOT more confident that my electrical system is in good shape now. Everything runs brighter. So THANK YOU for the patience and help to all who contributed.
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Originally posted by exzachtly1 View Post.....And then I really want to figure out the horn. I want that sucker to blow while the bike is just sitting.....
You can also measure the voltage at the horn - if it is low, there is voltage loss in the connectors or the horn switch itself is dirty inside. A relay is a "bandaid" to restore full voltage that should be available if all connectors are all clean.1981 GS850G "Blue Magic" (Bike Of The Month April 2009)
1981 GS1000G "Leo" (Bike Of The Month August 2023)
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