Frustrated and I think it's overcharging.

OK, '79 KZ650C3. Have a charging problem. Had one burned wire and meltec connector in the Regulator/rectifier plug. Volt meter ays it's overcharging at idle. Just installed a replacement Reg/rec. and fixed the connector. Same thing - still over charging. Yes. it does have a 2 yellow wire stator and a Dana ignition. Pulling my hair out on this "good deal on a used bike for the grandson). Going out tomorrow and buying a quality voltmeter. I have doubts about my inexpenssive (did I say cheap?) Radio Shack meter.

Anyone. Also have carb prob and I'm listing that in the carb forum if anyone was to pitch in there too.

Thanks for reading.

You state: "Volt meter says it's overcharging at idle"

What voltages are you seeing at what RPM, and where are you measuring voltage? Ed

+18V @ batt terms, at curb idle (1000 rpm approx.)

You're right, that's too high.

18V... assuming Vdc measurement so with that in mind....

Vac coming through the rectifier but not being regulated to ~ 12-14Vdc...
Is the replacement rec/reg unit new or used from another bike/this one?

Is the rec/reg unit grounded to frame/batt(-)...

Manual has various methods for testing electrical/charging systems, all procedures followed where resistance & voltage measurements within specifications...

My KZ650 manual is for 1980 and up, not sure if it's the same for year/model. Anyone have the OEM electrical test they can provide for Bear?

Follow the link to a KZ650 website for the 1980 manual... The site has good selection of KZ650 goodies, tech tips etc... Might find something there as well...

KZ650 Manual


Just in case you need...

Thanks Old Man Rock. It is a brand new Kawi factory replacement. It is mounted as was the old one. Two bolts to the frame and then the 3 pin conn. has a ground wire. Guess I'll have to trace that ground out through the harness. Perhaps it's compromised with corrosion someplace. I could also add a suppllimental ground directly to the engine ground connection. It's less than 1 foot away. Going to go to Radio Shack today and pick up a 2nd volt meter. Mine is older and perhaps in error. Need a 2nd one to confirm what I'm seeing.

If it was a 750 E1 4 cyclinder I'd say follow the brown wire. These reg/recs usually have a feedback circuit which tell the system when there is to much voltage. When this happened to me I found that one of the wires was just sitting in the connector to the reg/rec

Overcharging can boil a battery

Thanks JR. My plan today starts with a complete following of each reglator wire to it's termination. Hopefully I'll find something there amiss and fix the issue. However, in reading lots of forum topics here I do have concerns regarding the charging system when using the DSR (?) electronic ignition. In an attempt to fix a failure to exceed 5K rpm, under laod, I checked out the V at the coils. It was +8V with the batt at 13.5. I picked up on an idea posted in a forum to introduce a 12 relay to directly power the ignition off the batt. Essectially, thekey and kill switch is rewired to power a relay, and batt voltage is supplied through the contacts. It worked. Instant batt. voltage at the coils. Starting (cold or warm) was much improved. Mounted a Kuryakan LED voltmeter to monitor the batt and instantly it went +15 V. Confrmed this with an inexpensive VOM and observation of the battery top. There is evidence of spattering on top of the battery and the battery overflow pipe has fluid droplets in it. I'll pick up a new, better quality VOM today and verify the voltage reading. Thanks for taking the time to read and reply.

OK today we made a touch of progress. Ended up rewiring the White /red tracer to a new 12+ sense location. Also ran a new ground, black / with yellow tracer. No longer over charging. Now it's not charging. Recheck stator and V reg. everything is OK. I am beginning to bellive it's the electronic ignition somehow feeding back into the charging circuit. Tomorrow we try inserting a diode into the +12 of the ignition.