Topic: Bike stops dead electrical problem

[zabzob]

Electrical problem! Fun.

My bike occasionally stops dead while I'm riding it. No power to lights or anything. I have figured out that the issue is in the wiring under the left side panel. I have a solid state reg/rec, and have replaced the fuses with blade type in a four slot holder. When it stops, I push it to the side of the road, jiggle things under there, and the lights come back and I'm good to go.

I will obviously have to check it all, but there are only so many connections that could make me lose all power. Reg/rec for instance would just be a charging problem, verified by disconnecting it and still seeing lights on. I'll check the fuse connections and related wiring. Anything else to check specifically?

1975 CB750K btw. Thanks all!

[bryanj]

That has to be a main power connection loose at battery, solenoid or red wires at fuse box

[scottly]

You are looking for a problem on the red wire that runs from the battery + connection at the starter solenoid to the 15 amp main fuse, then from the fuse to the ignition switch.

[Medyo Bastos]

Wouldn’t you hear arcing with loose connections? Overheating will give you similar symptoms. While you’re at it, maybe check your plugs


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[M 750K6]

If you don't find anything there, I had a similar experience,  traced to a faulty contact on my ignition switch (back of the key switch).

[madmtnmotors]

If you don't find anything there, I had a similar experience,  traced to a faulty contact on my ignition switch (back of the key switch).

+1

[seanbarney41]

If you don't find anything there, I had a similar experience,  traced to a faulty contact on my ignition switch (back of the key switch).

+1

+2

[scottly]

I have figured out that the issue is in the wiring under the left side panel.    When it stops, I push it to the side of the road, jiggle things under there, and the lights come back and I'm good to go.

This sort of rules out the ignition switch.

[madmtnmotors]

I have figured out that the issue is in the wiring under the left side panel.    When it stops, I push it to the side of the road, jiggle things under there, and the lights come back and I'm good to go.

This sort of rules out the ignition switch.

Depends on how enthusiastic the "jiggling" is... 

My electrical troubleshooting regimen often involves figuring out what it's not, then moving to the next component. Intermittent issues can be maddening.

[zabzob]

Thanks all.

I put it on the center stand, vigorously jiggled the wires and couldn't reproduce the problem. I unplugged things from the harness until it was clear what could possibly be the issue and what was just charging/accessories. I pulled the blade connectors off the fuse box for the main 15A fuse and pinched them down a bit so it would be a tighter contact. Check the wires from the + terminal and all seems okay. I took it out for a good long ride and didn't have any issues. I think it's going to be a case of rebuilding confidence in the bike for the next few weeks...

[Deltarider]

Yes, but ride in defensive mode for the next period of time. I've learned that a sudden death, either electric or - like in my case - a hampered fuel flow, can turn into a matter of life and death when overtaking a car on a mountain road with uncomers...