stator voltage

I think I'm ok, but I'd like a second or third or as many as I can get opinion.

The bike: 1982 KZ750M/CSR, simple wire, kick only

When I got the bike it had a bad reg/rec. I replaces it, did a full simplified wire up. Boom charging great. Fast forward 1 1/2 months, it stops charging.

Test results:
White wire with red, battery voltage present
Black, good clean ground
Yellow wires 30vac at idle (didn't have enough hands to rev it)
Yellow wires show open when metered to ground
Using a Rick's Reg, no brown wire.

I haven't found an exact figure on what the stator voltage should read at a particular rpm, but most posts I found (2 ) said 30-40 vac at Idle

Am I missing a key thing that would kill a reg, or was I just the unlucky one to get a bad one?

Go to www.electrosport.com as they have a good troubleshooting page on their website. They also make replacement stators(the wire windings).


I'd imagine the testing will be similar to your 750:

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. Check only with the engine off !!

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.