Main fuse blowing when key turned

[silverkrown]

So I did some searching to try to find my answer before I posted but didn't have much luck. Here's my problem. Went out for a ride last night and everything ran fine, (has been running fine since I re-wired it). Today
I went out to go for a ride and nothing. Lights and power turn on but when I hit the starter nothing happens. The relay was cracked so I thought maybe that was the problem so I put on a different one I had laying around. Still nothing.
Check the starter button, clutch connection, still nothing. I happened to check the fuses and found the main one blown (should have checked those first).
Popped in a new fuse and turned the key and it popped. I have a multimeter and am not sure what to set it on when checking for a bad ground (which I'm assuming is what is blowing the fuse). It's driving me crazy that it worked fine yesterday and today nothing. Thanks in advance, oh it a 1982 GS650GL.

[chuckycheese]

There's a good chance that you've got a positive wire that's shorting out when it touches the frame (or something else that's grounded). A likely cause would be that the insulation is worn away in a spot...and it might be a very tiny spot. You're going to have to take a good look at your wiring. I think it's a little confusing that you had to push the starter to blow the fuse the first time, but that all you had to do was turn on the ignition the second time. If you start with the ignition and starter wiring, I think you'll find it pretty quickly. Good luck!

[silverkrown]

There's a good chance that you've got a positive wire that's shorting out when it touches the frame (or something else that's grounded). A likely cause would be that the insulation is worn away in a spot...and it might be a very tiny spot. You're going to have to take a good look at your wiring. I think it's a little confusing that you had to push the starter to blow the fuse the first time, but that all you had to do was turn on the ignition the second time. If you start with the ignition and starter wiring, I think you'll find it pretty quickly. Good luck!

I think it probably blew when I turned the key the first time but I didn't realize it. The good news is I went back out and checked some more grounds and connections and got it to start. Just got back from a long ride. Not sure if it fixed the problem, guess I'll find out if it starts doing it again.
Thanks for the help.

[chuckycheese]

You bet!

You're welcome! You may never know, for sure, what caused the problem. I had a similar thing happen a couple of years ago and it hasn't happened since. Be sure to carry a couple of spare fuses and hope for the best if you can't find any logical reason for the problem.