ARD "magneto"

[murph]

All right so,.....I'm working on a Harley 55 KH with an ARD ignition. The wiring is all over the place and not so nicely done. I'm trying to clean this up and take as many photos as possible but can someone give me the basic concept on how this system works? There is NO battery, it leaves the "mag" goes to a rectifier which then goes to an external coil. It still has a 12v regulator and generator. I just can't get it in my head in laymen's terms.

1955 kh.jpg

[dukekleman]

Murphy,
The system is AC magneto breaker point ignition. The rotation from the crankshaft creates AC voltage via magnets, iron core, wire and motion. This voltage is delivered to the ignition coil(s) primary winding and stepped up in voltage by the coils secondary winding. The breaker point in the magneto is used to time the point of ignition. It allows voltage flow when the point gap is open and stops flow when the gap is closed by shunting the AC voltage to ground.
Hope this helps...

[murph]

Where does the rectifier come in play? Is that taking the AC from the mag to DC to feed the coil? I'm not seeing an advantage or am I missing something? Thanks for the answers.

[dukekleman]

Ok, the wire you mention leaving the magneto would be AC voltage, then you mentioned going to a rectifier (Diode) which would convert it to DC voltage. This DC voltage must find its way to the generator system I will assume because DC generators require a DC power supply.
Is there a wire going from the ignition coils primary side to the Regulator for the generator? I would guess there is?

[murph]

I'll try to post pics when I get a chance. The way I see it is the "mag" plugs into the rectifier and out of that there are a red and a black to the coil and a green which went to a kill switch. The generator and voltage regulator are standard sportster stuff with the power coming from the B+ side of the bosche voltage reg. I assumed the ignition system and electrical system are two separate things as on a regular mag set up. Thanks for trying to explain.