Could this be coil related?

[kstrause]

I'm guessing here, so any input would be greatly appreciated. 1980 GS550E, carbs recently rebuilt, new battery, new plugs, newish regulator/rectifier, Dyna ignition. Bike starts up great and runs well. After about a half hour or so of running, if I shut it off and try to start it again it won't start. Let it cool down 20 minutes or so and it starts right up. Is this a symptom of coil failure?

Kurt Strause

[André]

Is the engine turn over fast or slow when you start? When it is realy hot my car start real slow then i release the key and try again usely it goes faster and start. Someone told me that my starter will be to change soon cause it is getting ground when hot. that make sense to me. Otherwise if it turn over fast enough to start the problem could be the gas don't flow from the thank. My late honda 650 had a vacuum valve on the fuel line, the hose from carb (vacuum) get kinkey once when hot it completely close so no more fuel to carb. Took me a while to find out and i stay stock on road twice due to that.

Good luck.

[tom203]

When you say it won't start, does it turn over but not come to life? But if you wait twenty minutes ( without charging battery ), it will come too life?
Also, if you didn't turn it off after half-hour, will it stay running?
You got two coils, it's hard to think that both would fail in such a way,at same time.Maybe you have an ignitor problem- does this bike have a pair of points or a signal generator?



( I missed the dyna ignition !)

[Redman]

Maybe ignition related, but I would not suspect the coils since there is two of them. Maybe suspect the pickup (yes, just one of them) or ignitor.
Does it happen sooner when it is hot out, and longer when its cold?

Other suspect might be tank not venting. Have you concidered that? Next time it quits, open the tank cap and see if it starts.

When it quits does it cut out quickly or does it run weak for a minute or so then stumble for a for another minute or so before it quits?

[kdo58]

sounds like my story

http://www.thegsresources.com/_forum/showthread.php?t=165044

[kstrause]

Thanks for the replies. Let me give you one more symptom which may give some insight. A couple of weeks ago the bike was not firing on cylinders 1&4. So I cleaned all the contacts to the coils, coming fromt eh ignition, etc. That seemed to clear things up.

Regarding the question about trying to start after its been running. It doesn't seem to run sluggish before it shuts off. Its only when I shut off the bike, stall, etc. and then try to start. The starter motor cranks just fine. It's like its not getting either gas or spark. I should say that I don't really smell any gas when I'm trying to start so I don't think it's flooding. Could be gas related then?

Kurt Strause

[tom203]

sounds like my story
http://www.thegsresources.com/_forum...d.php?t=165044

Yes,this thread sounds very similar.
Check and wiggle all connections from signal generator to ignitor and to coils; I'm baffled by why it just doesn't die after half hour, instead of refusing to restart for a while.

[Nessism]

In addition to the suggestions already given...how long since your last valve adjustment?