Not charging enough. Battery slowly dying.

Have you measured the Stator Voltage output, AC volts. If the stator checks OK, then measure right at the wire coming out of your R/R, before any other connectors. Then see what it is there, if OK then go along the path, to see where the voltage is dropping. You may still have a bad wire, did you look at the wires where they are close to the connectors? Any heat discoloration?

Look closely where the wires from the stator go through a rubber grommet, more than a few bikes have had problems there, when the wires have been twisted or show signs of vibration damage.

It's possible that the conductor inside the wire(s) has been reduced in size by vibration at the grommet or other tight places limiting the amount of current being supplied to the charging system.

Thanks Mfolks, I'll have a look at the grommet, is that behind the engine sprocket cover?

Motor Head: I have a separate Rectifier and Regulator on the B1. I had some heat discoloration on the white + cable coming off the rectifier, but I've trimmed the wire and replaced the bullet connecters with new, do you think that means anything?

To test the stator, do I just test each of the 3 yellow cables coming from the stator with a multimeter on AC? Multimeter lead grounded to engine and the other lead on the yellow? Sorry if this is elementary, but I sadly know less about electrical components then I do about engines..

Any combo of the three. One lead on one yellow, and the other on another yellow. Then switch to the last one. 3 Phase, should be in the 56 ACV range, @4K RPM.

Most alternators on these Kawasaki's put out 50 Volts Alternating Current (A.C.) which is then converted to Direct Current(D.C.) to charge the battery and run the electrical system.



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 I've made some progress, cleaned every connector associated with the charging system. I've also checked the stator using the instructions that Mfolks posted (thanks!) And the stator is funcfunctioning properly.

So this really only leaves the rectifier and regulator? Unless someone can think of sometsome i missed?

With a separate Rectifier from the Regulator, you should be able to test each. The rectifier takes the ACV and turns it to DCV, so check the Rectifier output to the regulator. Then check the output of the regulator, compared to at the battery. If the regulator output shows, say 14DCV, but voltage at the battery terminal is lower, than its still in the wiring. But if the output, right at the regulator is say 13DCV and the incoming voltage from the rectifier is higher than I would suspect the regulator. Most would probably buy the combined unit to replace either defective piece.
Do you have the service manual for your bike? There should be complete and through checks for this in there.

Also with a Test Lead, you can Add an additional say + wire from the output of the Regulator straight to Batt +, in series with the factory wiring. If the voltage across the battery goes up, then you have still an issue in the factory wiring between those two points. Then try the ground, one to Batt- the other to a clean spot on the chassis, or the casing of the Regulator.

OK I'll start with the rectifier. It has 5 wires coming out of it. 3 yellow which are from the stator, 1 white and 1 black, none of whch connect directly to the regulator. How would I correctly test the output of the rectifier and what am I looking for in terms of a reading? Also, the regulator has 3 cables coming out of it. Which would I test?

The white wire where it comes out of your Rectifier, then goes to the Y bullet connection. Try to test the voltage when running as close to the Rectifier as possible taking those wires out of the equation. this is also where you could add the Test wire, from close to the Rectifier, on the white wire, to Batt + post. this will add extra an conductor, if the wiring has resistance, a extra wire will carry the current.
This should send the voltage up Right Away. Do this quickly, if the voltage goes to over 15+ volts back off the throttle and stop the motor. Do it with a Meter hooked across the battery, and be ready to monitor/ shut down. You could pop some bulbs if you get much higher than 16-17 volts. you just want to find out if the system can produce the extra, then the regulator would be suspect.
to full field the Alternator to get full OutPut, apply full battery power to the Field wire. That should be the Green where it comes out of the Regulator.

OK, we're getting there. Tested the rectifier at the white and was getting 20+v depending on throttle, so I'm guessing the rectifier is good?

Then I connected the multimeter to the posts on the battery and disconnected the brown wire from the regulator while the bike was running lookking for a jump in volts, there was absolutely no change or jump in volts at the battery. Isn't this a little odd? If the rectifier is working correctly and I unplug the brown from the regulator, then shouldn't the volts jump up whether the regulator was good or bad?

no if the Regulator is not working properly, then it may not change at all. It sure sounds like the Stator and Rectifier are working. The system is capable, but being held back. Do you have another Voltage regulator to try? Or are you now in the Waiting for Parts mode? Maybe get the Combo unit, as it would replace all of those aging parts. OMR: (Old Man Rock) has a thread on the conversion and rewire for replacing the 2 piece unit with the combo. But it is pretty easy to do.
Me I'm waiting for the Paint on my fuel tank to set up enough to buff, I've wet sanded already. So no riding today.

No parts on order yet. Was trying to figure out what the issue was before I started ordering parts. I have a 78 kz650 which had a combo r/r so I can't swap out parts. Dang.

Anyone have a spare regulator kicking around for a 77 kzk650? Part 21066-018.