TOPIC:

Hello, I recently purchased a 1982 kz 1000. brought it home got it running and found it was not charging. after doing some tests on the electrical system i found that the stator was bad. replaced the stator with a brand new unit and now it overcharges. replaced the voltage regulator with two different units and i am still having the same problem. if anyone could help me out it would be greatly appreciated. Thanks, Phil

While overcharging, what is the voltage on the brown wire at the regulator?

Thanks for the reply, the voltage on the brown wire at idle is around 11.00 and at 4000rpms it's around 13.6

1ogkz wrote: Thanks for the reply, the voltage on the brown wire at idle is around 11.00 and at 4000rpms it's around 13.6

Ok, then the regulator/rectifier and alternator are probably working ok. If the battery is much higher than 13.6 at 4000 rpm, you have a voltage loss somewhere in the system.

The most common spots for voltage losses are the fuse panel, and the ignition key switch, in that order. Take out the fuses and clean the fuse holders. See if that makes a difference.

Brown wire voltage should be as close to battery voltage as possible. You can measure the difference directly by connecting the meter's black lead to the brown wire, and the red lead to the battery positive terminal.

Are you using a DYna S ignition? That usually makes the problem worse.

The Ignition is all stock, I'll clean up the fuse box and see what happens, Thanks again

battery voltage is the same at the battery as it is at the brown wire while the engine is off but while its running the voltage at the brown wire is around 1.45 volts

1ogkz wrote: battery voltage is the same at the battery as it is at the brown wire while the engine is off but while its running the voltage at the brown wire is around 1.45 volts

That is typical for this type of problem.

When you say "overcharging", then, you mean the battery is at about 15v, correct? That is too high, but is not severe. In the long run you will get battery boil-over, so you do need to correct it.

With a wiring diagram, you can use the voltmeter to find where the voltage on the brown wire circuit starts to change. It may be a series of connections that need cleaning.

You put the red meter lead on the battery positive post and probe using the black meter lead. This will show how much drop is at every point on the circuit.

If you have a diagram we can let you know where to probe to find the drops.

Thanks again, So basically the regulator is overcompensating due to voltage loss on the brown wire in the wiring harness. Would it damage anything other than the battery if i took it out for short rides till i get it fixed?

You may damage several things.
I have the same bike, and it had the same issue when I bought it.
The Speedo was Burned out from the high voltage. You could damage your instruments, or your ignition, besides blowing bulbs.
Do yourself a favor and address the issue now.
Also I never saw where you posted the voltage it is making at 4K RPM across the battery Terminals? 15v + is definitely a problem, and could cause damage. If its in the middle 14v that's normal.
Also a Bad or Weak Battery will also cause overcharging. But as Lou said, the brown sense wire voltage drop is super common on this model. The Main Fuse in your fuse panel will be some of it. Those things get hot, and tend to melt the plastic around the fuse clips, making them loose, and they get even hotter.
There is a wiring diagram here at KZR under "File Base" for your model.

1ogkz wrote: Thanks again, So basically the regulator is overcompensating due to voltage loss on the brown wire in the wiring harness. Would it damage anything other than the battery if i took it out for short rides till i get it fixed?

Correct. The brown wire is what tells the regulator what the battery voltage is at. If the brown wire is losing voltage, the regualtor thinks the battery is low so it sends more output to the battery.

To test/run it, you can temporarily run a wire from the battery post to the brown wire on the regulator. This will prevent any damage, and will allow you to confirm the reg/rec is working correctly. But it will prevent you from turning the bike off, so you will want to put a switch and a 5 amp fuse in the bypass line for safety. Switch this line on after the bike is running, and switch it off before killing the motor (to prevent the fuse from blowing). This switch will become a partial, secondary ignition switch and is not a permanent solution. (If you shut off the ignition switch, and leave this line connected with bike running, full current will be going through some skinny wires to keep the bike running, so the fuse is there to protect the wiring, but will blow if you forget to turn the switch off before killing the bike, or accidentally turn it on before the main ignition switch.)

If you don't do that, you will be ok for short runs (provided 15v or so is the max it gets to), but as you ride longer, the battery will get hotter and hotter and electrolyte will boil over faster. Then you must let the battery cool completely before going again.

EDIT I saw MH's post after posting: See motorheads post above for possible damage if the voltage exceeds 14.5 by several volts.

Can i pull the brown wire out of the regulator plug and use a female spade with a switch and a fuse right to the positive battery post? It's been killing me not to ride it.

Thanks, much appreciated. Phil