Got new terminals, wiring corroded under insulation

[Guest]

This is on my 81 650gl.

I removed the ignitor and R/R from the bike to clean up their main connections and add grounds to their cases. I found that the brass contacts had corroded to a purple color and had really high resistance. So, I ordered new terminals from vintageconnections and went to install them aaaaaaand...

The wiring is corroded inside of the insulation. Now what? Is it not even a problem and I can ignore it? (Eh, don't want to ignore it). Do I replace the harness? There are 12 unique wire colors. Do I order a premade harness or make my own? Premade is pricey, and homemade requires me to either buy a bunch of wiring myself or to give up some of the unique colors it has.


Any advice is welcome. I'd like to fix it up and sell it to cover costs to move out of the area, but I still care about doing it right.

Cheers

[posplayr]

Yes a new harness if best, but generally the corrosion only extends a short distance down the wire(under the insulation). If the copper is still flexible then just clean it and put on new ends.Use Naval Jelly to clean the ends and add new crimp ends. Once the current is inside of the copper wire strands it doesn't matter if there is corrosion inside of the insulation.

[WilliamGLX81]

I thought that electricity flowed along the surface of wire strands and never actually went inside the wires.
It's flexible, but I've already cut like 1-2" of insulation off and it's still corroded.

[posplayr]

I thought that electricity flowed along the surface of wire strands and never actually went inside the wires.
It's flexible, but I've already cut like 1-2" of insulation off and it's still corroded.

You are thinking of "Skin Effect" which only occurs at high (RF) frequencies. At DC (zero frequency) resistance is determined by cross sectional area which is because the current flows through the internal volume of wire.

http://en.wikipedia.org/wiki/Skin_effect

OK I looked at 60 Hz the skin depth is 8.5 mm. Pretty thick wire strands. Remember this at the strand level and not the whole twisted conductor thickness.

[WilliamGLX81]

Ah, all right. I looked into that too, but not in too much detail. So as long as the ends are clean (maybe soldered to the tinned bronze connections?), it should conduct despite the corrosion? Interesting.
So I guess I don't actually have to replace it.

[Brendan W]

I'd be careful mixing solder and crimp. You can end up with a more vulnerable connection. Check out the opinions. For me a crimp if done properly is effectively a cold weld and should do the job. Solder I reserve for switches and so on.
With my optimistic hat on a harness is innocent until proven guilty and sometimes the corrosion may extend only a short distance as Posplayr said. You may end up with a few extra connectors scattered around the bike or spend fruitless hours tearing your hair out to no avail. Either way a new harness is seldom going to be a straight in and out affair and has it's own charms.

[eil]

For me a crimp if done properly is effectively a cold weld and should do the job.

Only problem is that it can be hard to tell a good crimp from a bad one. You can mitigate this by having good terminals, good crimpers, and skill, I suppose. I have plenty of crimped connections on my bike but I still tend to prefer a soldered connection when splicing wires.

[Grimly]

I'm ordering some popcorn in - crimp vs solder is nearly as good as an oil thread
I'm with Brendan in this fwiw, if it's good enough for commercial airliners, it's good enough for Suzukis - if they're done properly, and you wouldn't believe how fastidious the aviation crimping is. While it's not impossible to get near that at home it's a matter of some expensive tools which normally wouldn't be justified, and a normal good-quality crimper and decent crimps will do just fine.
Of course, there's no such thing as a maintenance-free wiring job.

Oh yeah, to the OP; it's common to find greenish corrosion on 30+ year old copper, as I'm damned sure the quality of copper wire used in the Japanese car and bike industry back then wasn't up to the same standard as European wiring - probably a high content of recycled copper in it. When these cars and bikes were a mere three or four years old, the problem was starting to show, so it's nothing new and it's only surprising that 30 years on, the wires haven't got much worse. Having said that, if the copper is still flexible and the insulation is still good, they usually respond to a clean up and fresh connection made - good to go for another decade.

[Brendan W]

Was doing a bit of rewiring on an aircraft last week. The crimp terminals the owner bought have an extra bit for gripping the insulation so the wire core doesn't see the same kind of wiggling an automotive part might.

[OldVet66]

The proper terminals and tools are not that expensive or hard to use. The stock Suzuki terminals had a crimp around the insulation as well as a crimp that turned around the stranded wire and curled through the center of the wire.