Replacing Pick-up Coil Wires

[TADracer]

I have searced the forum concerning replacement of pick-up coil wires (not repairing them) and find nothing. After three decades of repairs I have been thinking of an outright replacement of the wires. At the same time I would like to try a different wire route inside the cover to give less bending wear as the wires move under timing advancement.

Changing the individual plugs for the ultra flexible wires at the harness is not a problem however connection at the coil itself seems a bit touchy. Also, what is the best type of flexible wire to use and is it even easily available?

Anyone ever do this or does anyone have any ideas?

[CaptonZap]

Changing the individual plugs for the ultra flexible wires at the harness is not a problem however connection at the coil itself seems a bit touchy. Also, what is the best type of flexible wire to use and is it even easily available?

Anyone ever do this or does anyone have any ideas?

No, it isn't, and yes it is. The wire used in old mercury bulb thermostats is ideal for the job, being very flexible, with what seems to be a silicone insulation.
On a set of pickup coils that I used on my test rig, the wires were both broken about 3/16 of an inch out from the coil plastic. I took some copper capillary tubing out of an old refrigerator and cut two pieces about .090 in long. I slid them on the two wires coming out of the pickup coils, and slid the two new wires in along side of them, and crimped the sleeves with a pair of wire crimpers, the kind with the finger that goes into the notch. Some heat shrink tubing over the connection, and some semi hard curing compound around the covered joints, to preclude movement that might weaken the wire where it goes into the plastic, and you have it.
A friend, that used to work for an electronics company, had a roll of the wire that is about what we want. I can ask him if there is a number on it. Or if he would sell some. It only comes in one color, but magic markers can help there. Check the Internet for wire suppliers, and you might find some with different colors. Then the problem is that they don't want to sell in less than roll quantities, and you need a couple of feet. Life is tough.

But short.

Let us know if you come up with any solutions, CZ

[crazy steve]

I hunted for a small quantity supplier, and this was what I came up with....
http://www.testpath.com/Categories/T...Fct7QgodNnAA9w
Still not cheap, but at least you don't have to buy a whole roll. This type of wire is extremely expensive (which is probably why Yammy spliced it) and not something you can find easily. I recall buying a chunk in a large size (like 500 MCM, or about 1.25" diameter) and it was nearly $100 per foot...

You might also try a larger hobby shop; the RC and slot car crowd might have something that works. You need silicone insulation, the various plastics won't hold up....

[barrelguy]

I read somewhere (maybe here?) that someone recommended wires from a multi-meter as these are subjected to a lot of twisting and bending from people constantly wrapping the wires around the meter before shoving it back into the tool box.

[CaptonZap]

I read somewhere (maybe here?) that someone recommended wires from a multi-meter as these are subjected to a lot of twisting and bending from people constantly wrapping the wires around the meter before shoving it back into the tool box.

Yeah, that was a suggestion. The only problem is that test leads, by design, have a thick layer of insulation to protect them from abuse, and that would tend to make them stiffer than the factory stuff, maybe inpeding the advance action. Don't know.
Next time I go over to my friends place, I'll find out what he has. CZ

[skids]

Yeah, that was a suggestion. The only problem is that test leads, by design, have a thick layer of insulation to protect them from abuse, and that would tend to make them stiffer than the factory stuff, maybe inpeding the advance action. Don't know.
Next time I go over to my friends place, I'll find out what he has. CZ

I used test lead wire and put a loop in each one to avoid kinks. It has been that way for many years. At first I was afraid that the insulation would melt from heat, but that didn't happen.

[CaptonZap]

I used test lead wire and put a loop in each one to avoid kinks. It has been that way for many years. At first I was afraid that the insulation would melt from heat, but that didn't happen.

Quick thinking, Skids

The large loop would reduce the stiffness factor by a bunch, plus reduce the bend angle in the wire, which would lesson the tendency to work harden and break. All in all, a good idea. Leave it to you engineers to figure this stuff out.
And the temperature in the chamber is never going to get hotter than the oil, and most plastics will take 250 or so, so the wires just get more pliable when hot, which helps with the following of the advance mechanism. A win win situation.
CZ

[crazy steve]

....and most plastics will take 250 or so, so the wires just get more pliable when hot...

Actually, they won't. Most 'standard' thermoplastic wire insulation is only rated to 60C/140F, the best is only 90c/194F. Go above their rating and you'll quickly boil away the votiles and the wire will get stiff; keep flexing it and the insulation will start to flake off and/or the wire will break.

Even the silicone insulation will eventually go bad under high heat, but will last much longer.

[CaptonZap]

Right you are Steve, I have small rolls of 100C wire in the truck for replacing wiring in furnaces.
That is 212degFar, and most wire will handle over their rated temp rating, just for liability purposes, so I wasn't too out of line. Mea culpa.

CZ

[TADracer]

The large loop would reduce the stiffness factor by a bunch, plus reduce the bend angle in the wire, which would lesson the tendency to work harden and break.

This is one of the reasons I am thinking of trying this. The wires are very flexible but the factory route inside the cover makes a few places where all the bending fatigue takes place. I figure there is alot of room inside the cover so why not use it to make a large, gradual loop and solve the problem

I figured finding the wire would be a problem but the copper capillary tubing connector CZ used sounds like a good idea. Whenever i do this I will make sure to take alot of pictures.

[bikerphil]

If you don't clamp the wires down in those 2 clamps on the backing plate, the wires will flex much more evenly, not causing the breaking problem, or at least nearly not as fast so I have found. Since I started doing this, I have never had a wire breaking problem and I run a lot of miles on both my bikes. I always leave a little extra slack under the cover by moving the harness up a little in the grommet, that helps not to put a bend in the wires near the P/U coils themselves. If needed, a carefully placed small tie wrap or 2 will keep the wires from finding any moving parts, just my 2¢, YMMV

[CaptonZap]

Right you are Steve, I have small rolls of 100C wire in the truck for replacing wiring in furnaces.
That is 212degFar, and most wire will handle over their rated temp rating, just for liability purposes, so I wasn't too out of line. Mea culpa.

CZ

Ooop's, lest Steve call me again on erroneous information, the wire is rated at 105C, which is 221 deg Far.
Whats 29 deg amongst friends, Steve?
CZ

[mmatches1]

Wire Gauge?

Just wondering what gauge of wire you guys recommend. The above supplier referenced offers many gauges up to 13 ga. Thanks, Doug

[slow mo]

i replaced mine with multimeter lines , you can buy a cheap meter or go to the source and they sell the wires ,,most multimeter wires are specked out higher than Yamaha,s original p/u coil wires ,,,ride safe slow mo!

[Lamric]

Yamaha used (at least) two ways to route the pickup wires.

This is the earlier, and more common, route... both pairs of wires come in at the bottom, one pair go anticlockwise to lower pickup, one pair (orange and blue) go clockwise to upper pickup.


This is the later routing... both pairs of wires come in at bottom, both pairs go anti-clockwise.


Presumably Yamaha was made aware of the pickup wire problem and changed the routing to try to solve the problem.