weird starting problem

[slantsix]

Hi everybody. I've been lurking on here for a while, so thanks for letting me do that.

Now I need your help.

My girlfriend has a 1985 GS400EF (sometimes called GS400S). It had been running pretty well all season, until last week when she went to start it, and it wouldn't. In fact, aside from a loud click (I assume from the starter relay?), it did nothing at all. I took out the battery, charged it, put it back in, and it started right away.

Fast forward a couple of days. I go to start the bike to warm it up, but it won't. And not the same problem as before, either. It definitely cranks and turns over, but it won't fire up. The fuel system looks good... and even if it isn't, there's enough gas in the float bowls to allow it to start.

Anyway... Compression was tested about 6 weeks ago, and that was fine. That leaves electrical. I can't find any frayed wires. The main fuse is good. The battery connections are good. There's spark (although a little weak.. I might try new plugs, but they're not bad at all).

Now, here's the weird part. Once in a while, while trying to start it, the dummy lights (and all lighting, actually) will just shut down altogether. When this happens, there's no electrical on the bike at all. Nothing. The only way to cure this is to completely unhook the battery, and then hook it back up again. It still won't start, but at least it turns over again.

I've gone over the troubleshooting guide in the manual, to no help. I thought that charging the battery had solved the problem, but it hasn'nt, since I've charged it again and it still won't start. Battery seems to be holding a charge.

Any ideas? I look forward to hearing some ideas. I'm all ears.

[cloudbreakmd]

Have you checked the ignition switch?

[steve-lloyd]

That sounds like a bad battery ground. Try unbolting the grond to the frame, then clean it back to bare metal and tighten it down hard.

[Dink]

Go to the home page, then to the gsgarage, run through the stator papers.
Clean every electrical connection on the bike. Especially earths.

Dink

[gremlin]

check and clean the fuses and the holder. some times thay will crode and heat up and lose contact

[tconroy]

Go to the home page, then to the gsgarage, run through the stator papers.
Clean every electrical connection on the bike. Especially earths.

Dink

Im with dink on this one.Clean all your grounds and start from there.

[bwringer]

Start with the easy stuff -- definitely try running something through the ignition switch and work it back and forth to get all the old crap out of there. I used WD-40 because it dissolves crud pretty well without damaging anything and it's cheap. Just stick the straw in the nozzle and run a whole can or so through the switch. You won't believe the crud that will run out the bottom.

Also check the ground connections.

[slantsix]

UPDATE on this problem.

Well, it turned out to be two problems. The bike was super-flooded (even several days after starting it, somehow. Even the air filter had gas in it) so I dried off the plugs and shot a tiny bit of ether through the airbox. Bike started second try. I don't know HOW it got so flooded, but I think my girlfriend was wringing its neck trying to get it started when the electrics weren't working.

And regarding that issue, it seems to be an ignition problem. Fortunately, I've got a spare parts bike, so if this issue shows up again, I'll make the swap. There's quite a bit of play in the ignition, which isn't a great sign to begin with.

Thanks for all the replies.... Very helpful. While I did read much of the Stator papers, I couldn't do much with it because it requires the bike to be running, which of course it wasn't. But in the meantime I've checked the main fuse, the battery connections, grounds, and ignition. Thanks very much!!!

[tconroy]

UPDATE on this problem.

Well, it turned out to be two problems. The bike was super-flooded (even several days after starting it, somehow. Even the air filter had gas in it) so I dried off the plugs and shot a tiny bit of ether through the airbox. Bike started second try. I don't know HOW it got so flooded, but I think my girlfriend was wringing its neck trying to get it started when the electrics weren't working.

And regarding that issue, it seems to be an ignition problem. Fortunately, I've got a spare parts bike, so if this issue shows up again, I'll make the swap. There's quite a bit of play in the ignition, which isn't a great sign to begin with.

Thanks for all the replies.... Very helpful. While I did read much of the Stator papers, I couldn't do much with it because it requires the bike to be running, which of course it wasn't. But in the meantime I've checked the main fuse, the battery connections, grounds, and ignition. Thanks very much!!!

check your crankcase and make sure you dont have gas in there.You can spray wd-40 down the ignition switch and see if it helps