Pamco question

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Hello,

I recently had a resistor on my Pamco burn up while I was riding down the road. Pamco Pete was kind enough to replace the ignition with a new one under warranty, but I am still trying to insure that I track down the culprit that caused my first one to go tits up. I have tested my PMA output (at the capacitor) and it went as high as 15v at idle, but generally hovered around 14.6-14.7v. I have read posts saying that this is too high - and I've seen other posts which appear to suggest that it is acceptable.

My questions are:

a. How high is too high, voltage - wise?

and

b. IF 15v is not too high, is it possible that the green wire on my Pamco, if it were to touch my bike's frame while the bike was running, could cause a resistor in my Pamco to fry?


I only ask about the second scenario because I relocated my coil mount and had to notch it to plug the wire into the coil. My clearance between the frame and the (previously uninsulated, it has since been remedied) connector was maybe 2mm. In the absence of a PMA / R-R issue, this is my next best guess as to what caused my failure.

***The green wire appears to be red in the attached picture, this is a first layer of heat shrink tubing.

Thank you for any insight you might offer, really looking forward to being able to ride again this weekend. :thumbsup:
 

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a. 15 Volts is considered to be the maximum. If you keep your headlight on it will absorb some of the power from the PMA and assist the regulation. The PAMCO is rated from 6 volts to a maximum 18 Volts.
b. No. If the green wire touches the frame it will just provide a continuous ground to the coil and the engine will stop because it is not getting the pulsed ground that the PAMCO provides with the green wire.

The thing that can cause the PMA to produce a high voltage (20+V) for a long time and fry the PAMCO, along with a few other things, like the headlight, is if the ground for the regulator is loose or intermittent. This is I believe one of the most common failures of the PAMCO caused by a high voltage from the regulator / PMA. People don't notice it because they tend to check the battery or capacitor voltage at low RPM's, like at idle. Crank it up to 3,000+ RPM to check the voltage on the battery or capacitor.
 
Thank you Pete. I tested my regulator again and it appears to be the culprit - it was going to 15.20 or so at idle. Is it possible to use the stock regulator of my '81 with my PMA?
 
Thank you Pete. I tested my regulator again and it appears to be the culprit - it was going to 15.20 or so at idle. Is it possible to use the stock regulator of my '81 with my PMA?

No. The regulator for a PMA works by shunting the excess current from the PMA to ground. The regulator for a stock alternator works by regulating the current going to the rotor. Two completely different systems.
 
Hugh's Hand Built sells PMA reg/rec's for $47.50. Brand new and are backed by Hugh. A great guy.
Leo
 
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