15.1 volts at battery

2005 KZ 1000P. 70,000 on the meter,,, assuming it is the original.
Trying to get my sons newly acquired KZ close to right,,, it was seriously neglected. First Kaw I have worked and first time I have had a motorcycle charging circuit act like this.

Checked all wiring and connections especially on the Brown wire. With headlight off it's 14.6... headlight on 15.1. Hooked in another regulator, (off a Honda) same thing. Stater shows good, 60-70 vac per phase. Coils 5-6 ohms, no grounds per megger. There is a 0.5 to 0.7 voltage drop from the battery to the sense (brown wire) at regulator plug. Checked the regulator rectifiers. check good on the multi-meter.

Strange thing is it doesn't jump to 15.1 when I turn on the driving lights that are on the fairings auxiliary circuit. (2 @ 35 watts). Only the headlight which I believe is 55 watt.

No offense to the Kawasaki crowd,,, but I'm not real impressed with the Kawasaki wiring on this bike. Appears they went the cheapest possible using 16 and 18 guage wire. This particular voltage travels all the way from the battery to the Ign Switch then all the way back to the fuses. Unnecessary voltage drop. Then One teeny little wire from the regulator to charge the battery. Even cheapo Honda used (2) 16 guage wires here to carry the current,,, and it was fused!

Well,,, 15.1 isn't super high but I am used to 14.4 to 14.6. What say you Kawasaki experts? Should I pop for a 775 Shindegen? About 200 buckeroos! but eliminates the sense wire.

Are you using a good battery (acid level on all cells ok)???

Brand new battery. (1 month old) Load checks good. Sorry,,, should have mentioned that

15.1 VDC is too high. I'd get a SH775. You can find used ones for less than $50 if you shop smart. I've been buying and flipping SH775's as a service for a while now and I've yet to find a bad one. Only thing to watch out for is fake ones and crashed damaged units with broken connectors.

The wire gauge is usually not a problem. If it was, the wires would start melting from the factory and would discolor everywhere. The voltage losses are at the fuse contacts, switch contacts, connector contacts etc. That is why the wires tend to heat up at the connection points.

So when you turn the headlight on, there is more draw on the pathway to the sense line. That increased draw causes more voltage loss. The regulator senses these voltage losses through the sense line and interprets them as low voltage on the battery, and thus increases output to the battery.

You can test it by temporarily running a dedicated wire from the battery to the regulator's brown wire connection. There could be a similar problem on the ground side, but start at the positive side first.

Yes, a regulator that senses through the output wire will fix the problem, but eventually you will have to address the voltage losses because they will start to cook the wire connections and will start to impact running by reducing voltage to the ignition.

These old Kaws were built to a price point in the day that didn't include chrome for the ages, best-practice electrical engineering etc.

We've traced many electrical gremlins on Z1's to excessive voltage drop across the ignition switch. KZ900's are likely the same. Symptoms include charging issues, weak spark, heat damage to certain connectors, etc.

The link points to a post we did a few years ago that illustrates why old OEM ig. switches can be problematic, and how to improve their electrical performance. There's no substitute for the coil relay mod in some cases.

kzrider.com/kunena/4-electrical/606810-z...-and-troubleshooting


Good Ridin'
slmjim & Z1BEBE

I own a '91 Zephyr 750 and have permanent voltmeter installed. I've also seen ocassionally 15 VDC also, and of course, is due to the the rudimentary regulator/rectifier in those days, and consider it common in old bikes, is just most don't have a permanet voltmeter to see it. Given the bike is 30 years old with no electrical problems, I did not think it caused any harm.

.................but just for kicks, I installed a Shindengen SH775, and it regulates the voltage a lot narrower and constant between 13.8 and 14.2 VDC depending on loads and revs.

The thing with the original brown "sense" wire is that it goes through the ignition switch, then the kill switch and feeds the ignition circuits too. My charge voltage was running high (sense voltage was low) until I added a relay to feed full battery voltage directly to the stock rectifier / regulator. While cleaning the ignition switch up is important, the stock wiring still has to go through a plethora of fuses, switches, connectors etc. to feed the B+ to the regulator. A voltage drop to the regulator brown wire causes batteries to get cooked. :woohoo:



I added a B+ relay to my sense circuit, that immediately lowered the regulator output voltage caused by low sense voltage. I feel this mod is more important than any ignition feed relay, unless it is feeding B+ directly into the regulator. The brown wire triggers the relay.


Although hard to see because of the ambient sunlight, it lays nicely across / between the harness plugs.

I agree 150%. Best move to make on the SH775. Works great.!!

No eBay APP ID and/or Cert ID defined in Kunena configurationHere is a nice SH775 for a fair price...

That Shindengen 775 regulator is priced right!

Are the plugs sold separately or do I improvise? I saw some kits sold with the plugs but prices are high.

ken19 wrote: That Shindengen 775 regulator is priced right!

Are the plugs sold separately or do I improvise? I saw some kits sold with the plugs but prices are high.

Here is the Triumph pigtail for a cheap price. I think the spade terminals can also be released from the Triumph plugs and inserted into the Kaw plug, but am unsure if this is actually do-able.
www.2wheelpros.com/oem-parts/triumph-lin...r-t2500676-part.html