6V regulator running a 79 KZ400B ?!

[Brendan W]

Ok so I am going to get this 4000 mile KZ400b back on the road. Still got the dealer sticker on, 610 W 57th street NYC
It hasn't run for two years but it did run OK. My son had it on the road for a year before he went travelling the world.
Going over it I find a sticker on the r/r unit. 6V Rs2152 Kokusan Denki.
Am I going blind?
It's a five wire, two yellow unit. The stock unit was four wire, two yellow.
Is it possible that it was keeping the bike going. He says he used the electric start all the time.
I recall getting a new coil and condensers for it when there were ignition problems and I know I checked charging voltages the day he bought it and later on.
Today the battery was less than quarter full and looks like it has a dead short in it now.
My gut says to replace the r/r.
What does the hive think?DSC_0065.jpg

[posplayr]

Charge up the battery and go a quick test. Double all your voltage reading to use a12v diagnosis guidelines.

[Brendan W]

Could I just saw the battery in half ?

[Brendan W]

Just to finish this up. Got a new battery and fitted a spare r/r unit.
Initially the charging voltage topped out at 13.4 Volts.
Were it not for what I have learned on here I could have either pretended it was good enough or junked it.
I already knew the generator was putting out and was not shorting, at least not at no load.
Figured I didn't need to do the tests and that the trouble was going to be the pos and neg drops to and from the r/r
A quick visit to the connectors to replace bullets with spades and rings and a SPG rigged up on the regulator mount bracket and now it's topping out at 14.3 Volt.
Thanks to Jim and everyone else who drills this into anyone who cares to listen.
Knowledge is the gift that keeps giving

[posplayr]

Good news. So you upgraded everything from 6v to 12v?

[Redman]

I had a 1979 KZ400B for 2 years.
Granted; that was 35 years ago, and I didnt have to replace the battery, but I dont recall it being 6 volts.

I cant find any info on " Rs2152 Kokusan Denki." other than that is a company that makes such electrical parts.

[Redman]

https://www.kz400.com/Techh%20tips%20bilder/Wiring%20diagrams/1979%20400,B2,%20G1.jpg

.

[Brendan W]

Good news. So you upgraded everything from 6v to 12v?

It's a 12 Volt machine. Just can't figure how it ran with a 6 Volt regulator.

I had a 1979 KZ400B for 2 years.
Granted; that was 35 years ago, and I didnt have to replace the battery, but I dont recall it being 6 volts.

I cant find any info on " Rs2152 Kokusan Denki." other than that is a company that makes such electrical parts.

Thanks for the wiring diagram. You can see how Kawasaki send the ground wire for the single phase generator directly to the ground return harness.

The spare unit I'm using is from a 3 phase machine, GSX 750 I think. Am I going to have trouble down the road sending the two wires from the Z generator into two of the three phase inputs on the r/r ?

[Redman]

.....

The spare unit I'm using is from a 3 phase machine, GSX 750 I think. Am I going to have trouble down the road sending the two wires from the Z generator into two of the three phase inputs on the r/r ?

You might have to try these two and then another set of the r/r inputs, becuse I think those regulators really only regulate one or two phases. (Not certain why I thought that. Somebody confirm or refute that, please.)

[Brendan W]

You might have to try these two and then another set of the r/r inputs, becuse I think those regulators really only regulate one or two phases. (Not certain why I thought that. Somebody confirm or refute that, please.)

Looking at the GS850 and GSX750 r/r inputs, both have Y, Blue/W & R/W inputs. In both cases either the Y or the Blue/W have the regulating bits on that phase so maybe dumb luck, but I chose the Y & Blue/W and it's regulating to about 14 Volts.