1982 KZ550 Weak Charging after New Stator/RR

Today I replaced my fork seals, and then took the bike for a short ride. I rode around for about 45 minutes, and the bike rode fine. I was accelerating after a stop light 5000 rpm in 3rd gear and boom the bike died. No lights or starter response at all. I tried to push start it and failed.

I pushed it home and brought out a multimeter, only had around 4 volts battery voltage. I put the battery on a charger while I ate dinner and tried to start the bike. The bike started however battery voltage was less than 12 volts and continuously falling. Per the service manual I revved up the bike and nothing changed, the battery voltage kept falling.

I also checked the fuses and the main fuse and holders were slightly burnt however still passed an ohm check. I replaced the fuse anyways but this did not solve my problem.

I did not check further as it was getting dark outside.

At this time I am unsure if the stator or regulator are bad. Any recommended checks besides pg 216-220 of the FSM?

I have not started the bike in 2 years, (accident) however I had no charging issues whatsoever before I parked it.

Does anyone have any experience with electrosport.com? They have the stator and regulator. Lower prices than partzilla and Z1.

Charging system problems often occur when the system grounds get corroded. That could be why the bike ran well before and is now misbehaving.

You can judge stator performance by disconnecting it from the R/R and checking no load AC voltage against the three different legs. You should get 65+ volts AC on each pair of legs at 5000 rpm. This is not a definitive test since it's no load, but it should tell you something.

Hook the R/R back into the system assuming the stator checks out, and make sure you have clean grounds. Try reving the engine up to 5000 rpm and check charging voltage at the battery. You should get at least 14 volts.

If it turns out you need a R/R, get a Shindengen SH-775. it's a "series" type R/R that will prolong the stator life. Try a google search for tons of info. As a bonus they are cheaper than most aftermarket R/R. Vastly superior product compared against a generic Chinese R/R like Electrosport sells.

Good luck and hope this helps.

Dis connect the battery. Charge it, then let it sit overnight. If it goes down to 4 volts, the battery is flat. Shorted cell. If it holds at 11 or above, it might be your charging system. A bad battery can fail in many ways. It can even destroy the charging system.
Steve

If not already done, would assure integrity of the ground connection where the negative battery cable connects to the rear of the engine.

Would also remove the battery, service the battery (if applicable), charge the battery overnight, and then have it load-tested for free at your local automotive supplier such as AutoZone, Walmart, etc.

Good Fortune!

If the battery has been sitting for 2 yrs, I would go ahead & replace it.
Be sure to properly service a new battery before putting it to use.

If the problem is the voltage regulator, you can use one from a late model Ninja 500 or Vulcan 500 to at least 2009. On the 550 I think it's virtually a direct plug n play. The newer r/r has the female terminal pins & I think your 550 is the same. easy to check. On my 81 650 the stock terminal pins & connector were reversed with the male pins on the reg-rec.

The battery was on a tender while it sat.

While I have no problem buying a new battery I don't think that is my problem. A properly functioning charging system should prop up the battery while the engine is running.

I'll buy some contact cleaner and q-tips, and follow the FSM's instructions.

What type of charger is it? If it's a smart charger, charge the battery, then check it with a digital multimeter. You should have at least 12.6 VDC, but a good battery will be higher (around 13.1 VDC).

High beam test. This is a test I do & the voltage numbers I use.
There may be a more accurate voltage reference chart on the internet.
Engine Off. Charge the battery w a good smart charger & verify the voltage (12.6+ VDC).
Turn on the headlight high beam - Ign switch On (Engine Off).
The voltage should drop, then slow or stop.
If it drops to 12.2 VDC, the battery is good. around 11.85 is okay.
If it drops to around 11.2 VDC, the battery may need replacing.
If it drops to 10.2 VDC or so, the battery is bad.

The high beam test removes the surface charge & gives a better indication of the battery's condition or something like that. (Ctek US 0.8 charger & VC97 meter)

www.oreillyauto.com/site/c/detail/SHU0/S...1&pt=N0360&ppt=C0005

Then I would charge the battery & do the High beam test.
If the battery is good, then on to the charging system. Clean & check the voltage regulator connector.

Ran some tests today. Multimeter leads measure 0.2 ohm when touched together.

The engine was warm for the stator tests. I connected a car battery directly to the battery cables so I had a lot of time to let the engine run.

All three yellow stator output wires measure 0.8 – 0.9 ohm.

Meter reads OL ohm between each yellow stator output wire and the engine case and negative battery terminal.

All three yellow stator output wires measure 49 – 55 VAC @ 4000 rpm. The VAC readings jumped around a little bit but my meter is inexpensive and probably not the most accurate at VAC measurements. A certain pair of yellow stator output wires read 49 VAC, slightly lower than the other two.

I believe the stator is fine.


RR tests -

With the red lead connected to the white/red RR output wire and the black lead connected to each yellow wire, meter reads OL on diode function, and OL on ohm function.

With the black lead connected to the white/red RR output wire and the red lead connected to each yellow wire, meter reads 468 – 480 on diode function, and 3.34 – 6.64 on 20M ohm function.

With the black lead connected to the black negative RR output wire and the red lead connected to each yellow wire, meter reads OL on diode function and OL on ohm function.

With the red lead connected to the black negative RR output wire and the black lead connected to each yellow wire, meter reads 464 – 469 on diode function and 4.2 – 4.55 on 20M ohm function.

I believe the RR to be bad. I expected OL readings on half the resistance measurements, but the other half RR resistance measurements should be much lower. Please correct me if my logic is incorrect.


I also had the battery tested at Autozone. I was told it was weak.

No eBay APP ID and/or Cert ID defined in Kunena configurationUsing ohm checks on non-linear devices like diodes can give wildly varying results which will depend on the specific type of meter you are using. I would suggest you move onto the DC voltage portion of the testing and see what you get.

(Incidentally, it should be mentioned that at least one of the manuals has the AC output tests with the wrong AC voltage levels. The 1-phase stators should be able to reach higher, I think around 70 VAC up to maybe 75 VAC, on the yellow wires. The 3-phase stators will only get around 50 to 60 VAC, as you found. I think mine measured around 55VAC. The errant manual has the two numbers reversed.)

The rectifier portion of the reg/rec may or may not be ok. In addition to that, one failure mode of the reg/recs from that era (after 30 years of service) is that the output voltage will slowly drop even when the RPMs stay constant. The voltage will seem to go up properly when the RPMs are increased, but after several minutes of sustained speed, it starts to drop, and eventually the battery will be draining.

The way to check for that type of failure is to mount a meter to the bike, temporarily, and measure the battery voltage constantly while riding. It's kind of dangerous, but that was the only way I could find that type of failure.

If you need a new reg/rec (not a bad idea to replace the 30+ year old one even if it seems to work), I found the mid 2000 Ninja 250's and likely the Ninja 500, have the same unit and can be had for dirt cheap if money is an object.

Here's one for $11. There are many others too. You will have to splice the wires to fit the connectors, but the colors are the same.


I can't remember if Martin found some that had the correct plug polarity or not.

Lou,

Your reply is very helpful as always. Thank you. What voltage checks are you referring to? I do not see any RR voltage checks in my FSM besides a battery voltage check while revving the engine.