1977 KZ650 not charging rewire project

Hi all,


I am rebuilding a wrecked 77 650 (front right collision w/utility pole). Structurally She is sound again.

I am doing research now before jumping into the electrical snafu's.

Most of the lamps were broken/smashed/missing so I am using led lamp sets and fasioning a new system.
(stop/marker/head/bright/turns/plate..)

There are shorts in the system, so sad, too bad. The turns & brights work intermitently. The horn doesn't work and the like....

The main fuse keeps blowing. The bike calls for 20 amp and I am using 25.

I was planning to rewire the whole thing from scratch. I found some wiring harnesses at the junkyard, but they look crappy so no thanks. I will use an appropriate guage wire, solder and shrink wrap and make my own.

Does anyone have any experience making new electrics for the 77's.

Black yellow = ground
Green = turn signals
Brown = switched 12v
How about the other wire's color codes?

I know enough about electronics to know that you can't just switch out components without changing impedances and such. This can cause other problems.

The system does not seem to be charging. This might or might not be caused by the shorts. I have researched the stator/regulator/rectifier.

I've been told that 1977 was the last year of the seperate rectifier and regulator. Can I combine these two by using (requiring rewiring) a later model's combined rectifier/regulator?

It looks as if someone added an electronic ignition component that "by-passes the points." According to a random helpful Kz owner met at local junkyard.

I want to re-wire from the ground up. What unexpected problems should I expect.

I am hoping that I can keep this project
around 500$+ time.

Can anyone offer help?

Cheers all and wish me success.

I totally rewired my 77kz650 last year, it wasn't so bad, it just took a lot of time and patience. I also did the coil mod, and I wired my own rectifier since I blew my old one out (there is a file in the filebase that shows you how to do it with radio shack parts). Change the tube fuses to blade fuses and fuse holder while you are at it, and other than that good luck! My system works a lot better since I re-wired.

Oh, and if your rectifier is bad, you might check your stator/field coil (whatever it's called on the 77) and hope that that isn't bad because that will set you back about $200.

The 77 kz650 is different from the other 650's. It uses an excited-field alternator. It cannot use the regulators from other years. Kawasaki did not make a solid-state, combo reg/rec for that type of alternator on a KZ. You will have to get an aftermarket one if you want to have a solid-state reg/rec for that bike. (Or you can make one, if you're experienced at that sort of thing.)

The alternator on the 77 650 is very unique and is a well designed unit. It has a stator and a field coil (the other years don't have a field coil). The weak point was the mechanical regulator.

The main problem you will run into is not knowing the function of all the electricals and thus the THEORY behind rewiring them. This will require lots of questions and patience. The other problem will be peculiarities of your model. The stator type is unique to your model so you will need to make sure you really understand how it works in order to wire it.

Colors? They are pretty much the same for most 70s vintage Kaws. I suggest you start looking at a wiring diagram for most any model to familiarize yourself with general colors.

yellow = wires from stator to regulator (AC wires)
dark blue = wire from oil pressure sensor
green/orange = wire from neutral indicator
black/yellow = ground
white/red = wire out of regulator that tees to
rectifier/battery
white = main unswitched lead to ignition switch
brown = main switched 12VDC; horn, aux lights, trigger
wire for regulator, turn signal
blue = lighting hot; it is what provides power for the
headlight and brake light
red = only used on brake light
gray/light green = (model dependent) turn signals
lighter blue = front running lights
orange/green = emergency flashers (some models)
black = clutch ignition interlock circuit
yellow/red = coil power
red/yellow = low beam
red/black = high beam
orange = turn signal switch control
NOTE! The wires that go TO and OUT OF the fuse box are different colors... you don't see them much as they come from the bundle behind the junction box. I have to look at a wiring diagram to get these sorted out.

The main issue with rewiring is your right and left switchgear. If you have a switch in your right switchgear with the ON/PO/OFF positions, this really complicates rewiring as this is an on/off parking switch for your head light. The headlights that are on all the time are a lot easier to wire. The junction panel on most models simplifies connections as a lot of the wiring is done behind the panel and if I were doing what you are doing, I would get a GOOD HARNESS from any model (except 78 KZ1000A/B or 79/80 KZ1000E) such as a 76 KZ900 or 77 KZ1000 (any model). Not only the harness but the junction box, small taillight harness and headlight/idiot light harness and switchgear. If you get all the stuff as a package, it is easy to install and you would only need to worry about wiring in your regulator and rectifier correctly.

Post edited by: wiredgeorge, at: 2007/01/19 21:04

just expect the worse! then it wont be so bad when you find out it needs redone.

i also had to rewire my 77 650 b-1, and it was time consuming! the PO (previous owner) said i need to get a new regulator and/or other charging system parts as he couldnt get the battery to stay charged. i charged battery a few dozen times , battery would charge and i could run a short distance before she died on me (5 miles or so)
finally i looked at EVERYTHING and seen cracked wires eveywere.
1 month later after i rewired it, it still did the same thing, no charging. wires are all new ,so
i took the regulator cover off to see and inspect it. low and behold i noticed that the + 12v ( brown i think,) wire for 12v switched power was going to the ground wire . i was confused how this happened with the color code on the outside of it! ( brown, black, green)
i soon remembered that the PO messed with it and he put cover on backwards, causing the + switched to become on the opposite side neg. i think thats why he sold/traded it to me , cause he just didnt pay attention to what he was doing!!!! i just turned it around and put all three back in color code and never had a problem yet
sorry to ramble, but this problem was theeeee biggest thing i had to deal with yet on this bike. it only took a rewired harness, 1 month of time and patiance!
also have a wire diagram if you need one?

Post edited by: steveo_4192003, at: 2007/01/19 22:15

77Davo650 said it will cost about $200; Anyone know where to get alternator/stator parts for the '77 650?