Melted wires from rectifier

[darrell3001]

Hello all,

1983 GS1100E restoration project

Bought this bike 5 years back from original owner. Bike was running/working fine last time i rode it about 2 years ago. Electrical system never gave me any problems. Just now getting into it to bring it back to its original glory. I noticed some "shade tree" work in the snake pit near the battery box. Upon further inspection, i found that the three wires that come off the rectifier were all melted together in the rubber boot just under the seat. The insulation was melted, but it did not seem that they had been shorted. However, the junction connectors were completed corroded to the point that they disintegrated upon attempt to unplug.

The "shade tree" work i mentioned earlier seemed to be an attempt to get better grounding. It would appear that the battery is grounded to the engine and rectifier/regulator is grounded to the frame, so my assumption is that this may 1) explain the melted wires and 2) explain the previous owners attempt to get better grounding.

So several questions here:

1) is my basic premise correct about the potential grounding problem the likely cause of the melted insulation of the rectifier wires?
2) Is there likely any damage to the rectifier/regulator? If i need to replace the rectifier, should i go with an after market type?
3) Is there likely any other damage to the wiring harness sans the 3 wires going to the rectifier?
4) If grounding is the culprit here, is there a better, more. professional field mod that i can make to better ground the engine and frame? I was thinking about a simple steel mesh cable used on a car to ground engine block to firewall.

Ive already decided that this is going to be a full tear down to bare frame and have frame powder coated. My point being that oxidation causing a grounding issue should not be a problem after the rebuild.

Thanks for your support and very best regards,

Darrell

 

[Redman]

....

1) is my basic premise correct about the potential grounding problem the likely cause of the melted insulation of the rectifier wires?
......

No.
THose three wires are most likley the three wires from the stator TO the r/r.
THey carry lots of current, all the time (especially with the original type of r/r). ANd those connectors easily get corrosion between the connnectors and between the wire and the connectors, and any little corrosion is a resistance to current flow. And current flow (amps) times resistance (ohms) is heat (watts). So is not excessive current causing the melting. As you may notice it is worse at the connectors, the sourse of the heat is the connnectors. IF it was excessive current the entire length of wire would be heating up all the same.
So, no, not directly related to the grounding.
Solution is to cutt off the connectors, and replace with new connectors. Will want a good crimper, not a $5 crimper-stripper from general hardware store that just crimps from one direction in only one place.

The above what I stated is somewhat common knowledge here on GSR, could have several people tell you that same thing.

SOmething I have found from my experience is:
Also need to cut wires back some. the overheating at the connectors has likley hardened the wires such that they are not ductile and the crimping is not as effective.
If you want a quick repair, especially if can not cut off enough of the brittle wire, or if you dont have the good crimps& crimper: use wire nuts (small blue ones or small grey ones) to get it back in operation.
SOme folks will scream in horror at idea of using wire nuts. But if use ordinary crimps from hardware store, especially on brittle wire, it will last a matter of days... at least that was my experience.

 

[Redman]

And there is also the discussion of using a newer type of r/r (a series regulator, not shunt). That involves a getting a different wiring harness and a different mounting.

 

[Redman]

Carlsbad CA.
Hey I was there several time. And rode Coaster thru there several time. When daughter and SIL lived in SanDiego and then Oceanside for 5 years.

 

[Rich82GS750TZ]

It's probably the single-most-performed mod/upgrade performed on the GS bikes. There are many posts here about testing and replacing the stator, if necessary; replacing the OEM shunt type R/R with a newer series type R/R like the Shindengen SH775 found used for around $50. New for around $100 at last look; and cleaning up the wiring, especially the grounds. There's a link to my charging system saga in my signature. There are many threads like it.

 

[darrell3001]

Carlsbad CA.
Hey I was there several time. And rode Coaster thru there several time. When daughter and SIL lived in SanDiego and then Oceanside for 5 years.

Haha!!! I ride the Coaster every day from Carlsbad to downtown San Diego. Also take Amtrak SurfLiner from Oceanside to downtown LA to a client site.

Thanks for you very insightful answers. They are very helpful.

Best Regards,

Darrell