Finding Charging System Fault

I have a charging issue on my bike. I get about 13 DCV at 4,000 rpms. I went through the following diagnostic flow-chart:
www.rmstator.com/PDF/fault_finding.pdf

It shows that the brown input wire to the RR should have something less than .2 V, I was getting 1.2 V so I apparently have a bad connection somewhere there. I have traced the circuitry for the brown wire and cleaned all the connections and no change in the input voltage. Not sure what to do/check next.

Is there a way to directly wire the RR input or to "fool" it someway?

Is anyone in the Grand Rapids area that could lend a hand?

Thanks,
Nate

Your battery should be fully charged before you do the flowchart or the readings can be wrong. Is your battery fully charged? Have you checked the stator output?

Yeah, Battery is fully charged and known to be good, stator is at 50 ACV for each of the tests which is to spec.

While you were checking the brown wire in the harness did you verify a good ground?

Not sure you have this so here goes anyways....

My KZ900 manual depicts 14.5Vdc as well and nowhere near that with all lamps and lights off... In researching this, can be somewhat normal for we need to remember, these are 30 year old rides and those specs where truly at the time of new out of the factory electrical measurements.

Would be interesting to know what others are actually measuring at 4krpm.... Possibly I'm wrong in this...

NOTE: What they are depicting is @ 4Krpm, you should see voltage changes when turning on/off your headlights. The only mentioned off 14.5Vdc is at higher rpm range, didn't say which rpm range....



If Battery voltage is 13Vdc, then charging circuit is most probably fine & working. This is still enough to charge the battery and when riding at even higher rpm's, this voltage will increase further for you...

Same time....

This is out of the KZ550 manual for electrical checks...

They mentioned 50Vac pending the number of stator wires, is this what you have (2 yellow wires)... Then 50Vac would be spec....

If you have 3 yellow wires off the stator then your 25Vac on the low side....

Perform the regulator test & measurement procedure and see what you come up with in resistance measurements...



OMR

What is the best way to verify a good ground?

Old Man Rock,
I wish the 14.5 DCV wasn't really a requirement but unfortunately after a few starts and a bit of riding I can no longer start my bike, so it is pretty evident I need some more juice to the battery(wish I had a kick start). My manual calls for 50 ACV for three yellow leads, which is what I am getting. I'll check the resistances on the RR, but I already know I have a bad input so I would like to get that figured out first.

-Nate

Best would be ground leakage testing/meter but long story of the applied theory...

Visuals... The battery negative (-) should be physically grounded to the frame and engine case... Start there where don't just look at it, remove the grounding bolt inspect the ground conductor round lug, use sand paper/emery cloth and clean to a shine on both sides of the lug, do the same on the grounding surface especially if the frame/engine had been re-painted...

For resistance measurements, disconnect the red battery conductor terminations...

Place your meter in ohm scale, place probe on battery ground and touch the frame with the red probe, should read your meters deflection of ~ .01-.02 OHMS.

Do the same but this time to the engine case, should measure the same.

You can basically follow your wiring diagrams where with the black probe grounded (battery ground potential) measure all your ground points throughout your electrical system.

"My manual calls for 50 ACV for three yellow leads, which is what I am getting."....
Interesting for the shop manual I have depicts for 3 leads you should have 75Vac.... Someone else here with a KZ550 to chime in would help....

Babbits on line also depicts two different voltage regulators, one with a ground wire coming off it and the other with no single conductor coming off it... Which one do you have?

The one with no wire would depict the regulator metal enclosure itself is the ground point to the frame.... As previously accomplished with your meter, insure this outer enclosure is at ground potential as well.


NOTE: If your stator is supposed to be 75Vac then this is a problem, not holding up when running a load for your shy 25Vac thus current under load conditions. Via OHMS Law, with a fixed resistance, voltage and current are directly proportional.

Same time @ 13.5 Vdc, your battery should be trickle charging enough to keep it topped off at 12Vdc... Seems you're on the right track where current is leaving the battery but not coming back in via the grounding....

Out of curiosity, with the engine running, 12-12.5Vdc on the coil voltages?

Your manual may also depict current measurements you can perform... yes/no...

This should give you enough to go on for now...

OMR

BTW... Another thing you'll need to confirm is if I'm reading your profile data correctly, you have a "'83 GPz550H2 w/'81 GPz 550D1 engine", is this correct?

If so, one stator may be different in output voltages and requiring different regulator/rectifier electronics... You'll need to confirm, test and possibly upgrade...

OMR

Update:
Reading 14.0 DCV output at 4,000 rpms, so I think it is good now. The issue was I just got a digital multimeter and it takes a long time to read a voltage it increases about 2 hundreths of a volt every second and when I left it on the battery terminals it finally leveled out at 14.0 Vdc.

I would still like to ensure that the ground wire is good. I cleaned up the connections and I still get about .2 OHMS. The lug rests directly on the frame bolted down with a bolt and a lock washer.

Ok,
Found that the issue on the brown wire(input to RR) was in the ignition switch itself so I rewired it to bypass the switch. Now getting .1-.2 V input which is what it is supposed to be and about 13.3 DCV output now at 4,000 RPMS.

I get a reading of about .15-.2 OHMS to the ground, and it is a frame ground, no engine case ground.

RR has a ground wire

Stator is supposed to be at 50 Vac and it is.

Stator is the same for D1 and H2.

Coils were getting 12.0 Vdc when I checked after I installed the WG ignition mod, about a year ago; the bike runs great, it just runs out of battery.

Does the fact that the multimeter changes very slowly, I mean it took a couple minutes for the meter to finally get to 14.0 Vdc. Is this a sign of an electrical issue?

Do you have a good analog(needle pointer) to use as a comparison? I've heard some digital multimeters are sensitive to magnetic fields from bike's alternators.

How fresh is the meters battery?

No digital meter I know of should take a couple of minutes to measure voltages....:blink:

Time for a new meter....

Harbor frieght tools... Automotive meter does voltage, resistance, current, capacitance, diode and TACH & DWELL! Nice little meter for $40...

www.harborfreight.com/cpi/ctaf/displayit...taf?Itemnumber=95670