charging system woes

So I built this bike but I obviously have no idea what to do with the wiring. I knew from the start that was going to be my hangups....

Here is what I got..

I built a chopper using a 76 kz200 as the donor, and installed a 76 kz750 twin motor.
I have learned from you fine folks that the 200 wire harness is set up for a single phase alternator, and the 750 has a three phase.
Also there are two looms coming off the stator housing, one with a green ands a brown, and one with three yellows.
I guess what I need to know is what combo reg/rect I can use, and how would I wire it up?

Any help greatly appreciated, I want to get this thing on the road by memorial day and this is the last thing standing in the way..

I don't have the 750 or the little guy manuals. But the three yellow wires are the AC 3 phase, then you would have the Neutral light switch wire, your green/ brown. Any of the later bikes will have the three phase system. Look for a regulator from 80 up. It should have the three yellow, it won't mater which of the 3 are connected together, and then a red/ white which is the output DCV to the + battery terminal, a black/ yellow which goes to a clean frame ground, and probably a brown wire which would go to a switched 12v source like the ignition or running light circuit. If it has the brown, this is the sense wire for what level it will charge at, so make sure where it is hooked into the 12v switched that the voltage on that circuit is within a 1/2 Volt of the actual battery voltage. If it is lower it will overcharge your battery/ boil the water.

No eBay APP ID and/or Cert ID defined in Kunena configurationWant the ultimate regulator for a three phase charging system? Get this one:


Comes with everything that you need to install, plus it's a MOSFET switching regulator that doesn't get hot and kill itself over time. I wish that I had known about these before I purchased a stock replacement on my KZ1000.

Thanks for your help guys. I went and bought that thing and it looks like it everything I need.
Will report back when I get it put on. I have yet to her the engine started but with the tank done and jerry rigged fuel fitting complete all there is left to do is get the timing set right and kick the shit out of it til she lights off!

So it is all built and I had it out on the road, put about sixty miles on it before i noticed I am not charging. The battery is slowly losing volts. I put on the new regulator, I am pretty sure I followed the directions well...

Here is a pic of the regulator. The three yellow wires from the three phase are hooked up to the plug on the left, the plug on the right has the hot and ground. I have hot and ground both going strait to the battery terminals like the paper said to.





Now I guess my next questions are:

how do you check the three phase generator to see if it is putting out?
What function do the wires on the unused plug play? was I perhaps unwise to not plug them in to something, and if so, into what would I plug them?

Just to clarify, it is a stock 1976 750 twin I am working with.

If needed, here's a link to the color wiring diagram from FILEBASE.

Click > www.kzrider.com/filebase/doc_download/281-z750b1

Good Fortune!

the red and brown wires coming off the alternator are the ones that are shown in the unused plug. the rectifier I have now is the same mosfet unit shown above and it has no place to plug the wires into. Should i assume that I need a separate regulator to go along with the mosfet rectifier, or should I run those wires to the battery, or should I leave the alone and disconnected as if they are irrelevant to my current charging problems?


By the way, thanks a million for the color diagram, the one in my pdf manual is in black and white!

Sounds like your wiring is ok.

Turn your meter to ohms and check each of the three leads to ground. If the meter changes (zeros, any number, etc) then the stator is dead/grounding. There should be no response from the meter when touching any of the three wires compared to ground.

To check the stator output set your meter to Volts and when touching any combination of the three wires (2 at a time), you should get over 50VAC when revving the motor over 3500rpm.

Good luck.

I've posted this several times, and it's handy to have in your toolbox/on the computer:

Alternator Testing For the Older 4’s(Z1’s,Kz 900’s, Kz1000’s,Kz1100’s and GPz1100’s).

To check to see if the alternator is working you need to follow these simple steps:

1. Fully charge the battery as this will be the power source during this test.

2. Disconnect the Regulator/Rectifier at the plug that has the six wires in it.

3. Start the engine and let it warm to operating temperature.

4. If you're worried about overheating, position a large fan for cooling the engine.

5. After the engine has reached operating temperature, have a helper assist you, and using a multi-meter, read the output at the three yellow wires (or the alternator output wires)at the disconnected connector.

6. Raise the engine speed to 4000 rpm, and see what the three YELLOW wire combinations(or any alternator output wires) are(1-3, 2-3 & 1-2). The output will be around 50 Volts A.C.(Alternating Current). BE CAREFUL, AS THERE IS A SHOCK HAZARD HERE!!

7. If any of the combinations are low or non-existent, the stator(wire windings) are bad and must be replaced.
Some of the older Z1’s and KZ900’s were reported to be phase sensitive, so check the wire colors carefully.

8. Using an OHMETER, Check the three wire combinations again, looking for a reading of 0.36 - 0.54 OHMS. If the readings are above or below, the stator may be bad and need replacement. Also check from any of the three YELLOW wires to ground, this will show if arcing took place.

9. Before ordering a new stator, check the connections from the stator as there are electrical "Bullet" connectors that may be damaged or dirty.
Inspect the wiring for signs of shorting or overheating too. www.z1enterprises.com sells replacement rubber grommets for the alternator output wiring, they get hard and could leak oil after a while.

10. Check the wiring coming out of the grommet as there have been situations where the wires were damaged causing a short(I.E. twisted together with insulation damage).

11. The sprocket cover will have to be removed to access the electrical connectors coming from the alternator, the left foot peg assembly and shifting lever will have to come off also.

ok, so i went out just now and did what you guys told me to and here is what I got:

1-2 .24 v

1-3 .24 v

3-2 .25 v

ohms were infinate, and the volts are surely a bad sign @ 1/4 volt?!

At 4k rpm's you should have 50 Volts A.C.(make sure your meter is set for VAC(Volts, A.C.) range of 200.

Yep, just double checked: I have an auto ranging multimeter, and on all three combinations I get 1/4 of a volt.

It looks as though it is time for a new stator?