Help with Kz750 charging issues

do you have another battery that you can swap in?

I bought a new battery today. When it comes in I’m hookup to test it.

New battery did nothing.

New 801 cell antigravity battery. New ricks Motorsport stator. New sh775ab r/r. Nothing. Still starts and charges at 12.30-40v. When I rev it it gets close to 12.90v or so. But isn’t it supposed to be close to 14v? I’m so freaking frustrated.

A resting battery is 12.6V

Right. My bad. This is with the bike off. It’s still charging though. I just got it in the mail. Probably not fully charged.

I'm still thinking you may have a wiring issue.
If your battery were low, the voltage regulator would be running the voltage up around 14.5V at 4k rpm.
So charging the battery to 13.6V won't really help bring your charging voltage up.

Try the tests I mentioned on the first page.

That has to be it. I’m gonna try and drive her to work on a Saturday and check the wiring then. I’ll do what you said on your first post. I know that my regular rectifier has 12v and a good ground. Maybe one of my three phase wires is shorted or something. How would I diagnose that?


I’m pretty sure I needed the battery anyway because my battery has been completely drained and apparently that’s detrimental to the battery. Plus I read somewhere that if the volts drop to about 9v on cranking it’s bad. Which the old battery did.

I’m honestly thinking it’s one of the 3 phase wires. That’s what imma check first. If I have 25-40v on the stator then I’ll look somewhere else.

start the bike
idle
meter on AC V
We'll label each stator wire as #1,#2,#3
backprobe the bullet connectors between the stator and the reg/rec
probe #1,#2 note voltage
probe #1,#3 note voltage
probe #2,#3 note voltage

raise rpm to 2k
meter those connections again

raise rpm to 4k
meter those connections once more

your AC V should go up as the rpms go up
they should be similar between each wire combination

turn off bike
put meter on resistance
disconnect stator wires from reg/rec
keep one probe on stator case(ground)

measuring the wires coming from the stator
probe #1 note resistance
move to probe #2 wire note resistance
move probe to #3 wire note resistance
all readings should be infinty or open or you have a short between the stator and ground.

Your old rectifier/regulator have 6 wires or 5?
And how many wires does the new reg/rec have?

Your new charging system will be .5V lower than the lead acid.
Rick's maxed the reg/rec at 14.0V for lithium ion instead of 14.5V for lead acid.

3:13 explains the voltage difference between the lithium and lead acid.

Excellent!!! This explains it very well. I’ll go through that process once I get the chance after work or something and note everything I. I believe that my old connector was 6 wires. 3 yellow. A red and a black. And I believe a brown. I left all those connections unplugged and wired my new charging system in. Then I wired the new system. 3 yellow wires from the stator to the R/R. One black wire from the negative battery post/common ground. And one red positive wire that has direct 12v from battery/ switched 12v. Really it’s just a constant 12v. So what am I missing?

What imma try and do is film each step if possible and send it here so you can see what’s up. Here is a test video.