Wiring break at headstock - cuts out on turning

[kramdra]

Cbr6, 113k miles. No previous symptoms. Bike can start, but all electrics and engine cut out when turning bars. Bars have to be turned or wiring jiggled to get electrics back.

Tuesday I rode through biblical amount of rain, but I have replugged all the connectors and pretty sure it is a wiring break, rather than a short. It was fine until Wednesday eve and was unridable.

Assuming it might be simple ignition switch wires, dont want to spend whole weekend checking the entire loom. Any quick way to fix this?

[Robby]

Not really a quick fix, and not the first time I've come across it. Wiring around the headstock is turning a corner and continually being bent and chafed against the headstock. Eventually a wire fatigues and breaks inside the insulation, or the headstock chafes through the insulation and a wire grounds out on the headstock.

Wiggle and bend the headstock wiring until you find the problem, then unwrap it and look. If the insulation has chanfed through you'll see it easily.

If a wire has broken inside the insultation, you need to bend/flex each individual wire until you find the one(s) that doesn't bend or flex like a normal wire, but bends like a piece of empty insulation.

To be honest, I would consider a new loom. If one wire has gone, others are likely to follow.

[Easy-X]

In my experience 9/10 times you can see physical damage. A complete break internally with the copper without even so much as a distortion in the insulation is unlikely.

I would inspect each individual wire near likely bendy places and I'll bet you'll spot something. Good luck!
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Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter

[WD Forte]

If you lose all power is has to be the main power related to the ignition switch
and cabling so not that bad to fix, you don't have to test the entire loom

A meter is your friend here, 10 minutes with meter can save hours of guessing
That and selective wiggling to force it into a fault state helps to locate the problem area

Sometimes wires snap at the 'neck' where the crimp is so very close inpection of the
ignition switch connector and terminals for breaks and corrosion is needed
It's also possible the switch contacts are iffy at 113K so keep wiggling and testing!

If the conductor has broken internally it isnt always obvious
I bought a bike dead cheap because a guy did the 'swap and hope' thing buying a new solenoid to no avail
when a quick meter check showed no continuity in the wire from the start button to the solenoid
I cut back the harness tape with a stanley knife,
cut the suspect wire mid bend to see which side had the break,
soldered in a new length of cable, sleeved joints,
retaped it and it was good as new.

While I'm rantin on..
I don't have the diagram to hand but generally, Honda colour conventions use Red for power in and Black ( possibly Red/Black?)for power out from the ignition switch.
RTFM
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bikers smell of wee