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Temperature sensitive charging system on 1985 K100 Wed Feb 13, 2019 12:29 pm
flyinglow
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I have a 1985 K100 RT with 35,000 miles that I purchased a year ago. I have added voltage and coolant temperature meters to the fairing so I can monitor these items while riding. My voltmeter reads a good 13.5 to 14 volts when driving. But, as the engine gets warmed up, especially on hot days, the voltage slowly goes down to about 12. 5 to 13 volts. I have a new battery and cleaned all the ground connections. The brushes look good so my guess is to replace the regulator with a new one.
![Temperature sensitive charging system on 1985 K100 20171010](https://i.servimg.com/u/f12/19/80/17/90/20171010.jpg)
![Temperature sensitive charging system on 1985 K100 20180611](https://i.servimg.com/u/f12/19/80/17/90/20180611.jpg)
![Temperature sensitive charging system on 1985 K100 20171010](https://i.servimg.com/u/f12/19/80/17/90/20171010.jpg)
![Temperature sensitive charging system on 1985 K100 20180611](https://i.servimg.com/u/f12/19/80/17/90/20180611.jpg)