Author Topic: Proper Charging System Test Procedure?  (Read 1285 times)

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Offline antleo

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Proper Charging System Test Procedure?
« on: August 01, 2016, 09:46:38 AM »
I have tried searching for quite some time and am probably just looking in all the wrong places as it seems to be a common problem. I think i may be lucky and just have a bad regulator (i doubt this, hence wanting to do full testing) as i get good voltage, but the voltage goes from about charging voltage at idle up to about 18 volts higher in the rev range(noting this I'm surprised the battery hasn't exploded or something yet)  anyways the bike is a 1980 CB650. the R R will be replaced with an automotive equivalent, but id like to check the rotor and such, so if anyone can either post or link to it id greatly appreciate it.

Offline flybox1

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Offline scottly

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Re: Proper Charging System Test Procedure?
« Reply #2 on: August 01, 2016, 09:54:28 AM »
Your symptoms indicate a problem with the regulator. It is the regulator's job to "throttle back" the field current to the rotor as the voltage gets up to about 14.5V. A bad rotor will cause undercharging, not overcharging. Also, be aware that the 650 charging system is different than the other SOHCs.
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