More electrical problems (starter relay wiring?)

[psyguy]

So, i am on a ride... stop the engine... when i try to restart it, it won't... no sound whatsoever when i press the start button at the handlebars.

I trace the problem to the starter relay, short the two poles and the engine starts .

Back at the garage i try two different starter relays but that doesn't solve the problem (symptoms stay the same).

Then i check the voltage at the yellow/green wire coming from the start button at the handlebars - and with the start button pressed in the voltage is ok, 12V.

BUT when i connect the starter relay (yellow/green) wire into the wire comming from the starter button the voltmeter reads 0V.

So, what am i looking at here??

[BassCliff]

Hi,

Did you trace the wire between the start button and the starter relay? It sounds like a short somewhere between the handlebars and the relay. Maybe under the tank? Maybe some insulation got rubbed off and it's shorting to the frame? Did you test the start button itself for continuity? i.e. pushed = short, not pushed = open? Did you check/clean all of the pertinent connections/connectors?


Thank you for your indulgence,

BassCliff

[Steve]

If he has 12 volts at the yellow/green wire at the solenoid, there is no problem with the wiring in the handlebar.

Psyguy, connect one meter lead to the solenoid case and the other to the battery negative terminal. Activate the solenoid. I'll bet you see about 12 volts there. If you do, you need to ground the solenoid. The solenoid is mounted on a rubber-isolated plate which is supposed to be grounded with a wire to the chassis. The connections on that wire corrode along with all the other connections on the bike.

.

[psyguy]

you da man, steve!

that's all it was - a missing ground wire from the starter relay housing

interestingly, the starter relay worked fine for a while without the ground wire

[posplayr]

For your consideration:

http://www.thegsresources.com/_forum/showthread.php?t=140109

There are Four (edited was three) connections at the single point.

1.) Wire to the solenoid ground
2.) Wire to the battery
3.) The R/R black wire ground.
4.) Frame Ground to closed spot.

The GS750EX has NOT had any charging issues since and I'm still running the OEM R/R to this date. If anything this is my daily rider, and although after a few days the battery gets weak it always fires nearly instantly.

[doctorgonzo]

I am in the middle of straightening out a similar problem with my 82 1000.

Would you clarify what you mean by a " missing ground wire from the relay housing"? Was it a wire that was not hooked up properly, or did you have to add a ground wire? TIA...

Todd

I am pretty sure a ground needs to go from the relay housing (a lug around the bolt that attaches the relay to the battery box is how mine is done) to a frame ground or neg battery terminal.

[Redman]

Yes, can have a problem that the r/r and the starter solenoid are "grounded" to the battery box and that plate over the battery box. But sometimes that battery box & plate are not well grounded to the frame and/or battery negitive, so the battery box is not really a good ground.

And Yes, there is suppose to be a ground wire (blk/wht) from the wiring harness that is suppose to better ground the battery box & that plate. But sometimes the other end of that wire doesnt make a good connection to the bike frame (either the connection gets rusty, or a problem with the R/R burns-melts the wire at some point in its history).

So, yes, that is why many folk recomend you add your own ground wire from that point on the battery box (were r/r and soleoid are "grounded") and run to the battery negitive, do this so do not rely on the battery box being grounded to frame and not relying on that blk/wht wire in wiring harness either.

.

[psyguy]

I am in the middle of straightening out a similar problem with my 82 1000.

Would you clarify what you mean by a " missing ground wire from the relay housing"? Was it a wire that was not hooked up properly, or did you have to add a ground wire? TIA...

Todd

the ground lug that goes onto the starter relay housing was not hooked up properly.
my ground wires in the wiring harnes are ok (and i put new lugs on) so i didn't need an extra ground from the battery box to batt neg.

[tlepac]

I had the same problem and a good ground to the main engine ground took care of the problem. Anyone want to buy an unnecessary Starter relay?

[doctorgonzo]

Cleaning up some of my dodgy wiring the other day, and I took a second big fat wire from the main ground (where battery is grounded at rear of the engine) to one of the bolts that hold the battery box down, then used this point as the location for all things grounded to the battery box.

[1982SZ]

Naw, on second thought.....

[doctorgonzo]

a. Pull battery, battery box, and clean up those 2 ground connections under the box.

If you have anything grounded there yes. I avoided grounding to the box totally because you are trusting the battery box to ground well to one of it's mounting bolts, and for that to ground well to the frame. It should be fine, but I had cases where it wasn't. By running a second wire from the main frame ground on the engine to a battery box mounting bolt and running all those underseat grounds there I am effectively grounding everything to one known good, easy to maintain ground location.

b. Check/clean the ground connection at rear of engine.

Yes, when I first put mine back together I didn't tighten this well and spent 2 hours trying to figure out why I had no power.

c. Add a ground wire from each the starter relay and the R/R plate, running each of those either to the Negative post on the battery or a good clean spot on the frame.

Starter yes for sure. R/R should have a ground wire already, but grounding the case sure isn't gonna "hurt", and might help.

[1982SZ]

ohh oh, I can't wait!

[posplayr]

Cleaning up some of my dodgy wiring the other day, and I took a second big fat wire from the main ground (where battery is grounded at rear of the engine) to one of the bolts that hold the battery box down, then used this point as the location for all things grounded to the battery box.

FYI, the only current that returns to the battery is the current flowing when the engine is cranking. Once you start to charge (R/R output exceeds the battery) all current returns back to the R/R (-) . There is is the reason for grounding R/R (-) to the frame.

There is a common "mis-perception" that while charging currents flow back to the battery (-). This is not true.

All currents exiting R/R (+) have to return to R/R (-).

Excuse me for continuing this low level drum beat.

[posplayr]

Hmm, I translated Docgonzo's input as to say..." a good way to ground the battery box thoroughly is by grounding it to the main engine ground, and then you're much safer to be grounding off of the battery box itself."...?

Ever read Pirsig? Anyway, where do you think I should start my electrical eval. and with what tools?

I have never read Pirsig, but just looked him up. I guess perhaps there is a cult like following of him and or his books. There is a more modern perception of what he describes. It relates entirely to the human brain and left side v.s .right side characteristics. (left is logical and right is creative). With only having read the brief synopsis these seem to correspond to Pirsig's These two sides correspond to rationality (left) and romanticism (right).

The more modern interpretation embraces the fact that the human brain should operate in both modes for optimum problem solving and that this can be effected not only at the individual level but also organizational (see 6 Sigma). It has been described to me that a key indicator of high IQ is how fast an individual can switch between left and right brain behavior.

I was just about to graduate high school when this book was published. Unfortunately I have too much rationality to indulge my romanticism that might be evoked by the title.

http://en.wikipedia.org/wiki/Robert_M._Pirsig

http://en.wikipedia.org/wiki/Zen_and_the_Art_of_Motorcycle_Maintenance:_An_Inquiry_into_Values

As far as your lectrics, run a ground from the R/R (-) to the nearest frame point (rear air box mount works).