Coil wire splicing - suggestions?

[ClutchSmoke]

Finally lost my patience with the misfiring on my '78 11E, and decided to check the coil wires.

As soon as I pushed a little slack into the wires, while jiggling them, the bike quit.

It looks like there may be a break in one of the wires close to a pickup coil. The bulge in the wire is closer to the pickup coil than I would like, so making a reliable repair may be a little more difficult than I was hoping for.

It appears the only way to test the wires is to poke a hole in the insulation, or cut the wires completely off. Correct?

Since I probably don't have a whole lot of room for error, I'm kind of wondering what is inside the little boot where the wires attach to the P-coils. So I can leave some wire there to work with, but still cut it close enough to get the problem spot.

Are there in pictures of a dissected pickup coil around?

(Don't wanna mess up, as finding parts will take too much time & $$)

[DiverRay]

Take a look on the left side of the page. Go to the Tech Tips, and look for the electrical then pickup coils. This should show you everything you need to repair the coils.
Ray

[Ken Talbot]

Haved a look at this article from the technical section here at the forum. IIRC, the bit from Ken Talbot might have a picture or two in it...

[ClutchSmoke]

Yeah!

That's what I was looking for. The article I had been looking at was the one under the "Tech Tips" link to the left with the "new/updated" gif beside it. (no pics.)

I wish my wires had broken a little bit further out. Guess I'll just have to take my time getting it right.

Thanks.

[DiverRay]

When you put it back in, leave the "crimp" for the wires a little loose. I also leave a little extra in the area, as you CAN pull some down from the outside of the cover.
Ray
Ken DOES take good pictures.

[ClutchSmoke]

I'm thinkin'

I'm gonna totally replace the wires. I found several weak spots in addition to two broken spots (as shown by the hourglass shape during the pull test.)

I'm going to try to put little connectors on the pickup coils, and then build little flexible wire sections that lead to more connectors before they leave the engine case. (To make them less susceptible to corrosion.) That way, the wire should break in the future somewhere on the section between the connectors, and I can just pop in a prefabricated spare section. Just have to find some small connectors that won't bind or get caught on anything while the advance rotates.

I have plenty of old computer mouses (mice?) and that wire seems to be similar in flexibility to the original factory wire, so it won't impede the rotation of the vacuum advance, and it is wire designed to be continually flexed. I even tested the wire in the freezer to see how stiff it would get. Seems it'll be fine, even when I occasionally ride in 10-20F degrees. Just kind of wonder how well the insulation can withstand engine fumes/oil residue. I suppose it can't be much worse than multi-meter leads, I believe they are just covered with PVC.

I am cursed by Murphy, so as soon as I fabricate my new fangled, removable coil wires, I'm sure one of the pickup coils will crapout.

[DiverRay]

I bought a roll of MML wire from Radio Shack. That is what I used to repair my daily ride. If you leave the crimp loose, the wires shoould last for 30 years!
Ray

[skids]

What "crimp?" Do you mean the thing that bends down over the wire pairs to secure them in place?

Originally posted by DiverRay
I bought a roll of MML wire from Radio Shack. That is what I used to repair my daily ride. If you leave the crimp loose, the wires shoould last for 30 years!
Ray

[DiverRay]

That's the one. I wrote Yamaha about the problem in mid '78. I was working at Gilroy Yamaha at the time, so I did it as a Yamaha mech. They never did loosen the crimp, and that is just about the place most of the breaks happen.
Ray

[andreashweiss]

In case you need a complete pickup coil assembly.(what's under left engine sidecover) everything in there off bike with 40,000 mi price includes shipping $75.00 andreas

[ClutchSmoke]

I couldn't find good enough quality connectors...

So I just soldered and heat shrunk the wires where they were broken and weak.

Makes a hell of a difference!