TOPIC:

Bike started acting up yesterday, and I'm not sure where to start.
The thing just dies momentartily, and then mysteriously comes back on. I think it's in the primary circuit, because I only lose power in the ignition system. Everything else stays on.
I checked my fuses, and they all appear to be working, but I did notice that the fuses and wiring in the fuse box were moderately warm. Almost hot. Is this normal? Or should they be cold?
The open (or short), doesn't seem to be related to movement of the front end or bouncing around or anything. I'll start it, it runs for a little bit, then dies without me touching anything. I'll try to restart it, and it'll crank some, then it'll start, run for a little, then suddenly just die again.
At one point yesterday, I took the tank off and jiggled my coil connections, put it all back together and it ran fine. Got us all the way home without skipping a beat. Then when I tried to ride it again, it started doing the same thing.
Would an ignition module act like this? Or would it just go out and stay out?

Am wondering about possibility of fuel starvation (for whatever reason) causing the problem.

Perhaps a clog in the fuel tank vent (test by running with cap ajar), or petcock screen (includes up inside tank), or in-line fuel filter.

Might also consider flushing out the fuel tank.

Good Luck!

Thanks Patton, but I really don't think it's a fuel delivery problem. I've had them before, and I wouldn't lose all four carbs at exactly the same instant.
Gotta be electrical.

those "ghost" problems are hard to find, I bet you will find a loose connection, or even a wire that has been pinched long the way

I had a problem a little like this one.

I had a broken wire on the on/off switch located on the right bar . it was inside the unbroken insulation AND inside the protective wiring sheath. a difficult find indeed

might be an intermittent open elsewhere

the key switch base does this too but you'll have to scout it out for sure.

Well I went through everything I could find under the side covers and tank. I did find the wire going from the ignition cover to the igniter had brittle and broken outer covering, but the individual wires inside appear to be fine.
Put everything back together and took it for a ride around town and it ran fine.
I hate it when something gets "fixed" and I can't figure out what it was.
Gonna take it for a longer ride this afternoon. Damn sure gonna take some tools and wiring stuff with me.
Oh, The main fuse looked like it had some solder flux inside it. Maybe the fuse came unsoldered and then resoldered itself. I put a new one in, and I have four extra ones just in case.

riverroad wrote:

... only lose power in the ignition system. Everything else stays on... Would an ignition module act like this? Or would it just go out and stay out?

If Dyna-S, would check and assure good connection where power wire to Dyna-S taps into switched battery voltage harness wire. Relying on the plastic pinch-clip instead of solder could allow the tap-in connection to get loose and cause intermittent power to the modules.

Good Luck!

I wonder if your key switch has worn out?

Try this, fill the carb bowls and then remove the fuel tank. Start it up and before it runs out of gas start bending the harness in different places to see if you can get it to die. It might have a bad wire inside the harness somewhere.

OKC_Kent wrote:

I wonder if your key switch has worn out?

Try this, fill the carb bowls and then remove the fuel tank. Start it up and before it runs out of gas start bending the harness in different places to see if you can get it to die. It might have a bad wire inside the harness somewhere.

On my 750, it was the ignition switch doing it.

Do you carry a lot of keys with your key to the bike? weight may a problem wearing out the ignition switch.

I've seen this problem with ignition switches in cars prematurely wearing out because the driver has 2 lbs of keys along with the car key hung on the ignition switch.

Thanks for all the input guys, but I don't know what to think now. I took it for a nice long ride all over town, made several stops, and she never missed a beat.
I really hate it when something like this happens, because it's not really fixed, just postponed it I think. Hopefully it won't happen when I'm out in the middle of nowhere.

If not already done, would inspect the connector where wires from the modules feed into the igniter. Might be loose, cracked, melted, corroded, or otherwise defective, and resulting in intermittent signals from modules to igniter.

Good Luck!