Melted wiring harness!

[Guest]

Took wifes' 81 450 for maiden voyage to day (been redoing since last Sept. Bike was doing pretty well although some small issues. All of sudden everything on bike went dead and it had blown the main fuse (only one it has). Tried changing fuse and it blow too. Almost off the connections on this bike have been replaced along with new spade fuse holder. So dumba_ _ I am I bypassed fuse long enough to get home, which was only two miles. Well of course I now have a meted wiring harness, so bad there is no way I can cut and splice. Now that I've stopped crying, I thought I'd ask if anyone has one that might work on this bike? (Will post in want ads too). I do have a harness off a 78 550 that might work but wiring is different at one point because 78 had reg. and rectifier separate. Anyone have a wiring diagrahm for 78 550, looked on Basscliff but didn't see one. Does any one know where to get a new one that would work. Thanks so much terrylee.

[Nessism]

I suggest a wiring harness from a bike with electronic ignition - 1980+, since your 450 has same. I adapted a 1000G harness into a 1000S so anything is possible as long as you are willing to do some grafting work.

[BassCliff]

Hi,

On my site there's a GS550 service manual for '77-'82 models. There should be a wiring diagram in there for the '78.


Thank you for your indulgence,

BassCliff

[chef1366]

Sorry Terry
I hope you find the short

[terrylee]

Thanks guys! I'm hoping a new harness will take care of the short if not I'll fiqure it out. Sorry Basscliff didn't see it! One of the guys has one from a 81 550, that should work right? terrylee

[Larry D]

How badly is it melted ? Is there any way to cut out the affected wires and replace them with some connectors of some sort ? Seems an easier way to go rather than replacing the entire wiring harness.

Of course you need to find the reason it melted and repair that first.

EDIT:: Nevermind.....I missed that sentence in your original post.

[terrylee]

Melted into a blob from top of airbox to triple tree, so nearly impossible to cut out, although I thought about it, but I just don't think it is to easily done. At least it is only the main harness all the sections which connect to it are not fried. terrylee

[GabrielGoes]

Melted into a blob from top of airbox to triple tree, so nearly impossible to cut out, although I thought about it, but I just don't think it is to easily done. At least it is only the main harness all the sections which connect to it are not fried. terrylee

i feel your pain 100% man. in my opinion just save it man, i know all about melted harness's lol i would really just save the harness i spent 12 hours all night saving mine, no waiting for shipments or anything, get'r done!

[terrylee]

One of the good guys on here has one off a 81 550T and it has a fuse box set up instead of just only one main fuse for the entire bike. So I would like to switch over to that. I pretty good with most elec. so I think I can handle it, anyone ever done this, if so any tips. If I have a wiring diagram for the 550 I think I can figure it out. terrylee

[terrylee]

ok, need some advice. Got the wiring harness for the 81 450 (bought one on ebay from 81 550T). Since it was set up for a fuse box I installed a new spade type and got all the wires hooked up according to diagram for the 550. Which looks to have come off a bike from Canada( at least according to diagram in service manual off of Basscliff site). Everything was exact match for what was left on 450. Everything works except the taillight, headlight and lights for speedo and tach.
The 450 even though it is a 81 has a on/off switch for lights, which always worked before I melted old wiring. All wires going to left handlebar switch are exact color and order match for where it plugs into main harness. It seems like the on/off switch is not turning anything on, I'm getting no juice to anything it controls. Did test the plug for ignition switch and getting juice coming into red wire of plug, but nothing when I touch the orange, brn, or gry. wires. with the key on and the ign. switch plugged into harness. But bike will start right up. I have double and tripled checked all connections which I either cleaned or replaced and can find nothing wrong. Help! My wife is dying to finally get to ride this project bike, which is ready to go except for this problem. terrylee

[GabrielGoes]

Everything works except the taillight, headlight and lights for speedo and tach.

The same exact problem for me as well.... If you followed the connection from the tailight headlight and speedo and see nothing is touching or melted and there all hot try to check the Left handlebar switch, open up the plastic compartment held by 2 screws on the bottom and take a good look. i gaurentee one of the soldering ends is off or is just really a bad connection... its the only reason i see all 3 not working simultaenously(sp?). Get inside the switch and just solder the connections on the switch again, if you have to bypass the switch and solder them all together so the headlight is always on... the test light always helps, test lights dont lie and sometimes the problem could lead to the key switch... the contacts could be dirty... i think 1 screw hold the key switch in place directly beneath the key area... its gotta be the switch on the left handlebar!

[terrylee]

Thanks for response. Did recheck ign. switch plug and am getting juice at red and org. wires, but nothing to brn or gry. Haven't tried taking handlebar switch apart yet, but will try that tonight. Although I did have a old handlebar switch of same kind from parts bike, plugged it into harness and still got nothing. Will also check bottom of ign. key switch (I did have to change out wiring on it recently while doing all this project, because wires were fried to it) so maybe the switch is a problem. When you turn the key on the oil, and neutral light on dash do come on. terrylee

[GabrielGoes]

When you turn the key on the oil, and neutral light on dash do come on. terrylee

same thing happend to me! its gotta be a bad switch connection i mean for the dead wires i would just follow it all theway up to where its connected/soldered

[terrylee]

You were right the org. wire inside the handlebar switch was disconnectd. So soldered it back on and it worked! Then put all the wires back into headlight bucket and turned key on and the fuse to the lights blew. As long has I leave the switch to off the fuse is fine, the second I turn it on the fuse blows. Had spare switch so cleaned it up and put it on plugged it into main harness and does same thing. So know it is not the switch at least. Will be taking all the wires back out of headlight and checking all them for short or something. Didnt' start blowing fuses till after put back together so I figure it has to be something in there. terrylee

[terrylee]

help! going insane!

I pulled the headlight and checked all connections and inspected all the wires for fraying and could find nothing. Tried hooking back old handlebar light switch and still blew fuses. If I put the bike in the "park" mode (so only tail light comes on)it comes right on and doesn't blow fuse. I unhooked all connections in bucket one at a time and made no difference. The only thing I can think to do is cut cover off headlight wires in the main harness and follow them as far as they go and look for a short. I went through 25 fuses! I even changed where the fuse for the lights on the fuse box plugs in to a different spot and still no change. I feel it has to be the headlight is the problem since tail light will come on and not blow the fuse, as long as headlight switch is on off. terrylee