Odds of a 34-year old wiring harness being OK

[Ledyard]

I've just started rebuilding/restoring a 1978 GS750. I'm trying to get it to stock, rather than do any modifications, but am planning to replace the petcock, all the gaskets, o-rings, and basically anything rubber.

What are the odds of the wiring harness being sound? Should I plan to replace the entire thing so I am dealing with healthy wiring from the start?

Thanks!

[koolaid_kid]

Most of us clean/replace the connectors and the harness is fine. Depends on whether it has been hacked up or not.

[sedelen]

Both mine were good, only had to rebuild the tail section on my GS1000 because PO had some bags or something not original on it.

[tkent02]

I haven't had to replace one yet, except when some tard cut it all up.

[Nessism]

If I were starting my bikes restoration anew, I'd restore the harness by removing the brass terminals out of the plastic connector shell and clean each one to remove corrosion. HCl acid works well to remove corrosion from the darkened brass. Then I'd pinch down the female sockets and reassemble the terminals back into the shell.

Did this for the charging system legs and saw a significant reduction of harness resistance.

Doing this kind of work is a bit tedious but not difficult once you get the hang of extracting the pins.

Good luck

[Ledyard]

Thanks all -- my electrical incompetence is rivaled only by my mechanical incompetence, so the wiring makes me a little nervous. A completely new harness is close to $200 though, so I may try to clean up and save the existing one. It does not appear to have been messed with, but there is a good deal of corrosion and just general old-ness.

[open1mind]

Led- where did you even find a new harness? I tried searching for one for my 79 GS 1000 with no luck. I would gladly pay 200 for a NOS one if it is out there...

[SqDancerLynn1]

One word of advise ! If you remove it make sure to take pictures of wire routing and lable everything

[Dogma]

Other than dealing with the connectors, inspect the entire harness for chafed insulation or brittle wires. I've had to replace long stretches of wire that were far enough gone that the bike would die if you moved the harness.

[Ledyard]

Led- where did you even find a new harness? I tried searching for one for my 79 GS 1000 with no luck. I would gladly pay 200 for a NOS one if it is out there...

BikeBandit has them listed as available... I haven't checked to see if they actually have them.

[spyug]

There is no need to replace the harness unless, as they've said, it has been hacked up. Look for cracked insulation or exposed wire of course but, as Ed says, spend time on cleaning the connectors. Most electrical issues can be blamed on corroded connectors. Corrosion causes resistance in circuits and that means voltage drops from point A to point B.

One of the worst circuits to be so affected is often the ignition and if you test, you may find a drop of 1.5 to over 2 volts from the battery to the coils. Obviously, low voltage here can cause all kinds of starting and performance issues.

As mentioned, it is not hard work but can be tedious so a little bit at a time and you'll get the job done.

Good luck with it.
Cheers,
Spyug

[Nessism]

BikeBandit has them listed as available... I haven't checked to see if they actually have them.

Part# 36610-45005

Shows as available. $163

http://www.boulevardsuzuki.com/fiche_section_detail.asp?section=94665&category=Motorcycles&make=SUZUKI&year=1977&fveh=2133

I'd order it. Cheap.

[Ledyard]

Part# 36610-45005


I'd order it. Cheap.

.... and, done.