What to do next? Electrical short.

[joe penoso]

I went to start 1979 850 g and motor was cranking over , I turned headlight on smoke started escaping from my battery ground wire. The plastic melted. Electrical problems are my weak link. Any suggestions what to do next aside from taking it to a mechanic?
Thanks
joepenoso

[Brendan W]

By battery ground are we talking about the big black wire from the crankcase to the battery negative?
First thought is that the supply to the starter motor is shorting to the case or frame because the insulation has worn or The connection post on the starter itself is touching the
starter cover.
Get the battery off the bike and inspect the supply to the starter.
If we are talking about one of the smaller black and white ground wires you could have a short somewhere in the harness to the frame. Usual suspects are near the steering stem. Check that the ign supply and return wires, red and orange, are okay over their full length to the ign switch and back. Did any fuse blow?
Any chance of a picture.

[Steve]

First, let's separate the events.

1. You were cranking the engine and turned on the lights. Did you move the headlight switch WHILE you were still pushing on the starter button or had the engine already fired up?

2. Smoke appeared from the battery ground wire. Which one? There are usually three. The largest one goes to the back of the crankcase and grounds the starter. The other two are much smaller and handle the other electrical stuff on the bike.

If the engine was already running when you moved the headlight switch, the starter is not the problem. The problem will be in the headlight circuit.

If you moved the headlight switch while still pressing on the starter button, you have some wonderfully flexible fingers. In stock condition, you would have to simultaneously pull the "choke" control, pull the clutch lever, push the starter button, move the headlight switch. One other question in this scenario: why increase the load on the battery WHILE starting the engine?

Hopefully it was one of the smaller ground wires that melted. You should also find a wire of another color (ground is black with a white stripe) that shows signs of heat damage.

.

[Redman]

Which ground wire....?

If one of the thin ones, I would suspect the connection on the thick one on back of engine. If that is bad, then some of the starter motor current (the highest current draw by far) would/could be going down on of the thin wires, and then that thin wire is almost like the heater wires in a toaster.
(I assume by "cranking" you mean running the starter motor.)

[Baatfam]

A couple simple photos would go a long way towards solving this....

[joe penoso]

Found it ! Thanks for your help.
joepenoso

[Rich82GS750TZ]

care to share?

[Steve]

Found it ! Thanks for your help.

OK, what was it?

Whose suggestion helped?

Not closing a help thread by posting the results might get your privileges revoked.

[Redman]

Found it ! Thanks for your help.
joepenoso

? ?

? ?

[Brendan W]

Smoke leak repair

http://whereisbobl.com/tiger/smoke.html

[joe penoso]

PREVIOUS DECEASED OWNER TRIED REWIRING TAIL LIGHTS, TURN SIGNAL AND BRAKE LIGHTS TO WORK WITH VETTER BAGS. THERE WAS A COUPLE OF SHORTS AND and to put wiring tape over ground wire leading to battery. You guys are the best. I need to start a new thread to check turn signal relay options.
Thanks
joepenoso

[joe penoso]

Couple rear brake light were touching, a few other small things;
Thanks
joepenoso

[Brendan W]

Previous owners ingenuity knows no limits.

[salty_monk]

Was he lynched for writing in bold caps in red on a forum

Glad you found it, doesn't sound like it was too painful a process!

[Brendan W]

Was he lynched for writing in bold caps in red on a forum

Glad you found it, doesn't sound like it was too painful a process!

Well, you know what happens after you spot the first fish in the river. Just saying