1983 KZ750

Wow! That's pretty messed up. You need to look at your wiring diagram from the manual. martin_csr gave you a link that has a wiring diagram. Looks like the white wire (III) is part of the ignition (with key being part of this circuit) and regulator-rectifier circuits and should be going to the positive side of the battery. This ignition circuit wire is red/white and on the opposite side of the fuse from the white wire. As mentioned, it is connected to the ignition key, which when turned on, will feed the coils and electronic ignition. The fuse with the blue wire on one side of the fuse and brown on the other seems to be for lighting. The other fuse with the blue/red wires seems to be lighting as well. Not sure about the black unconnected wire (I). And the other wire (II) I can't tell color.

That white wire is a big part of your problem. That is why you are not getting any juice to your coils. Please!!!!! don't take my observations as being correct (I'm only looking at a photo). You need to study the wiring diagram yourself and then have a good multimeter to test and verify everything. Good luck.

I figured it was going to be something nasty like that. I am wondering if it would be worth it to just change out to blade type fuses, and replace connections and bad wires.

May be a good idea if you see a lot of splices. loadhvx on here has helped many with the wiring diagrams. You should check some of his posts. But I would first just try to fix what's there for now so you can evaluate the rest of the bike's needs. Its not like you are going to be riding it anytime soon and need the electrical to be perfect.

ravenz07 wrote:

Here is the same pics but I have highlighted a few things.

(1) This wire is not connected to anything, just a loose black wire

(2) Another non connected wire

(3) I am pretty sure I remember this not being hooked up to anything when I first turned the key and the lights come on. Interesting since should be the main fuse right?

(4) Not sure what is going on here but it looks pretty thrashed

I and II are most likely the same wire. Most of our bikes have "spare unused" ground and power circuits for adding accessories (usually one in the battery area and one up near the headlight). I would assume this is the spare ground for the battery area. As for the rest of your wiring, I would recommend the same as KZJOE900...fix what's wrong for now, to get it running, but then I recommend replacing the entire wiring harness once you get the electrical figured out. Loudhvx is great for helping with the electrics, as is MFolks, and I myself just rewired my kz750 e3 and can help with most of it as well.

Definitely. What good is a bike with a rebuilt motor with sloppy wiring?

I may have to recruit my father on this. Maybe we can get it sorted out before too long and I can hear the thing come to life.

Or at least check the compression

Cant seem to figure this out. It seems like some places are not getting power. I think the light fuse keeps blowing as well

Have you got the wiring Diagram? What model is the 750? Here is a wiring Diagram in "FileBase" that should be OK to go by: kzrider.com/filebase/doc_download/317-z750h4

The Wite wire comes off of the post on the solenoid where the battery cable connects, then to your fuse box. That is the main power lead for the Bike electrics. It must have a Good Fuse and supply power up to the Ignition switch. Once the Ignition switch is turned to ON then you should have power back at the Brown Wire. That would help a lot. Do you have a test light or Volt meter?
Black wire with yellow trace stripe is the main ground color through out the bike. If you find another color hooked to ground there is a very good chance that is where you are blowing fuses. You can leave the fuse for the Tail light circuit out for now and just try to get it to have Spark, and Cranking from the Button.

Motor Head wrote: Have you got the wiring Diagram? What model is the 750? Here is a wiring Diagram in "FileBase" that should be OK to go by: kzrider.com/filebase/doc_download/317-z750h4

I looked at the following wiring diagram KZ750-L3 Wiring diagram and I noticed that some of the wire colors are different between the two diagrams. You should confirm which diagram relates to your bike.

ok i have a kz750 myself...and i want to run just the bare minimum electrical...ive already done away with turn sig.....im in the process of bobbing....does anybody have an idea?im new at this sorry...
thanx

hi nice bike you have i have two of them and i have bin around the bike and it wires if you know what i mean lol i can get you pics if you wish the first thing i will say is you can get rid of your accessory fuse holder unless you have something that uses it its the little plastic thing with the red n white wire going into it you will need to have the head light installed i have an airbox , and the closest model to your bike is the 82 kz750 R1 or GPZ as some call it

I would greatly appreciate some pictures! The more the better!

Raven,
Hey just saw this. I have the KZ L3 site, and I still happen to have the one I bought new way back in 83. For good measure I bought an 82 Kz750R (Gpz) recently so I have both in the garage

You definitely have an L3, the one piece handlebar (GPz has clip ons) and the chrome engine covers give it away. The L3 is pretty obscure, but having put a 113,000 or so on mine I can say it's a nice bike to ride.

That said, I'll get you a picture of the wiring tomorrow.

here's a picture that shows the seat of the GPz (the BMW sometimes gets in the KZ shots). The seats are idenbtical between the L3/Gpz as is all the bodywork. The gauges use the same physical size package, but the 82's are more involved. You can mix and match, but to put 82 gauges on the 83 takes a bunch of sensor work. or you can just ignore the blinking red lights.

Parts for the 82 are way easier to find, most of the engine parts from the 81/82/83 KZ models works too.

Great to see another getting on the road.