1981 gs850 wiring issue

[Guest]

Hi there. Received a 1981 Suzuki gs850g in a trade and am having some issues getting the start button to work. I took some wiring off to install a new start relay but got distracted for a few months and can't seem to find any info on where two wires go back to. If anyone has any help it would be much appreciated. Also any troubleshooting guides for the electrical would be awesome. Thanks

[Brendan W]

Hi Whisjeyjack, welcome
This is our library where you will find wiring diagrams and service manuals and lots of useful stuff posted by dedicated olds over the years.

http://members.dslextreme.com/users/bikecliff/

The black/white wire is one of the ground returns. They usually were screwed to the airbox top mounting screws when new .
Can't see a colour on the other.
Check out Posplayrs sig for a different take on how to organise the grounding on these machines. SPG , single point grounding as tags to search the web.
The starter relay need an earth wire. The plate it's mounted on is most likely isolated with rubber bushes.

[Whisjeyjack]

Thank you Bendan. Got it all wired up correctly. But while trying to get it started the start button just stopped working. Do you know why it would do that? I jumped the relay and it tries to start that way. I took the button apart and cleaned it with contact cleaner. Not sure what else to try.

[Steve]

Are you pulling the clutch, or has that "safety" switch been bypassed?

.

[Whisjeyjack]

Never tried it before but I took the slider switch under the clutch apart and shorted the wires and hit the start button and it was still a dead button . I'll try taking the button apart again and see if something fishy is going on there. Otherwise I'm out of my depth I guess lol.

[Steve]

If you have a test light, there are a few easy tests you can make.

First thing to test is to see if power is getting to the starter solenoid. If not, then you can start backtracking to see where it is lost. Connect your test light (you can use a volt meter, but it's not as convenient) lead to the battery negative terminal (or any good ground. Touch the battery positive terminal (or the battery terminal on the solenoid) to verify that the light is working. Touch your probe to the solder pad on the solenoid that has a yellow/green wire on it. Turn the key ON, press the starter button. Power? Yes / No

If Yes, touch your probe to the case of the solenoid and push the starter button. Power? Yes / No
If Yes, you need to ground the solenoid to the chassis. It is mounted on the battery case, which is rubber-mounted to isolate vibration. It also isolates electricity, so needs a ground wire.
If No, you need to replace the solenoid.

If you did not see power at the solder pad, pull the fuel tank. Follow the electrical cable from the throttle grip on the right side to a 3-pin connector. Two wires will be orange/white. One of them will also have a red band around it. With the ignition key ON, check for power on the red-banded wire. Yes / No
If No, check your fuses.
If Yes, move your probe to the other orange/white wire.

With the ignition key ON and the kill switch in the RUN position, check for power. Yes / No
If No, move your kill switch back and forth a few times to see if your light flickers. Might have dirty connections on the switch.
If Yes, move your probe to the yellow/green wire.

With the ignition key ON and the kill switch in the RUN position, press the starter button look for power on the yellow/green wire. Yes / No
If No, you have a bad or dirty starter button.
If Yes, remove the headlight from the bucket, look for two connectors that have yellow/green wires. One side of those connectors comes from the "safety" switch at the clutch lever, the other side goes into the main wiring harness. If you wish to bypass the switch, open up those connectors, put the two on the main harness back together to themselves, bypassing the clutch switch. But, before you do that, use your test light to check for power at those connectors. I don't know whether the male or female connector should be the one to test, so do both. I am suspecting it is the female, but can not guarantee it. If you have power there, check again at the solenoid.

.