Buzzing headlight

Hey everyone,

I bought the bike with a dim headlight, previous owner just used high beams at all times and I saw no issues for years. After a new battery and regulator/rectifier this weekend, the low beams make a buzzing sound, and everything dims when I hit brakes/turn signals. Do I just need a new headlight or do I have an issue in the wiring harness? I get ~ 10v from low beams, and ~4v on high beams, but high beams seem bright, so I'm confused.
Also, is there a problem with running high beams always? there is no kill switch for lights, but starter cranks just fine with the brights on

Thanks

You should be getting very close to full battery voltage at the headlight. With the engine off, you should get more than 13v across the battery, and should lose only a few tenths at the headlight. Four should not be enough to get light, so your meter or method likely needs attention, too.
You should probably plan on disconnecting every wire connector on the bike (one at a time) and carefully clean them with electrical contact cleaner and assure that each one is making good contact. Then retest.
Carefully check ground wires. Unhook them, clean the connector and the spot it connects to carefully, and reconnect insuring that each is snug.
Also be absolutely sure that your battery is good. Brand new ones sometimes fail. A load test will confirm its condition.

Using the high beam only may be illegal where you live. And if it is working properly and is properly aimed, it will blind oncoming traffic. Both are bad ideas.

Also check the wiring carefully for broken wires, or missing insulation. This is often a problem between the steering head and the inside of the headlight cover. The wires get a lot of exercise there and can rub against the frame and the headlight cover, creating paths for electricity to escape.

From the diagrams at Partzilla, the 1982 KZ550-C3 Ltd has a reserve lighting switch, so that thing cold be defective or something. All I know about the device is that it will keep one filament on if the other goes out, and I think it's supposed to automatically dim the high beam if the low beam filament fails. The Kawasaki service manual probably has a troubleshooting section for it.

27010-1024 SWITCH,RESERVE LIGHT


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Martin is right. Low beam is burned out. Do you have a H4 headlight?
Steve

The headlight diagram shows a lens unit & H4 bulb.



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Mine did also. Who knows what the PO put on it. :whistle:
Steve

Does the buzzing sound change to a higher frequenzy with higher rpm of the engine?
If so your new regulator/rectifier (wrong wiring?) made an AC and not a DC voltage to your electric system.
Just a thought.....

I might help to mention exactly what voltage regulator was installed. part number. new or used. that sort of thing.
I would charge the battery with a good smart charger & do a load test. Then do the charging system checks outlined in the manual.
most of the tests are pretty easy. and test the reserve lighting device.
I have a Scorpion AGM battery, Ctek US 0.8 charger & VC97 digital multimeter.

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