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Bit-O-Magneto History

From 1952 to 1965 the magneto was manually retarded by cable through twisting the left-hand grip for easier starting.  As the bike gained speed the rider would twist the manual advance grip the opposite way in order to advance the ignition timing. A lot of riders would manually adjust the distributor or magneto by leaning over and physically moving the unit back (clockwise) for starting. After the bike was warmed up, the rider would manually advance it (counter-clockwise) by hand before taking off. Many times a spring would hold the magneto in position. In 1965-66 up until 1969 this all changed. The distributor ignition timing procedure became automated. While different parts were used the 1970-1977 points system used the same automated system, as did the earliest electronic ignitions in 1978 and 1979. This automated system utilized a centrifugal mechanical flyweight assembly that advances and retards ignition timing. 

Generator & Regulator

The generator is a brand new chrome 12 volt replacement.  We bought a 299750-65A generator and an Accel solid-state voltage regulator (201104).  We thought the 12 volt setup made much more sense than the stock 6 volt system.  Maybe we'll even be able to work the lights in the dark!  The generator is polarized by hooking a 12v + source to the A terminal and momentarily connecting the negative post to the F terminal.  The generator is just a bolt on replacement, provided you drill out the mounting holes in the timing gear cover to 5/16".   

Mounting the regulator was a bit more interesting.  In this picture, you can see the solid state regulator just under the seat and bolted to the frame with a bracket we made.  Hopefully, the regulator is in a place where it can get a cool breeze and not fry itself.

The wiring from the generator and battery eliminator was run under the tank and wires for the tail lights, brake lights, and oil pressure switch were run down through the seat post to the bottom of the bike to keep the wires out of the way.  Ok, well maybe we've been watching Biker Build-Off a little to much but it does keep things clean!

Battery Eliminator

We used an Accel battery eliminator, 151308, from V-Twin (32-0548).  Hopefully, this will keep us from having to mess with a battery and clutter up the rear section of the bike.  It's tucked nicely up under the bottom of the tank and visible only if you're laying on the ground... and Kade and I are usually the only ones that do that!

Lighting

Lights run off the generator and battery eliminator.  See the Wiring section below for the details.

Headlamp

For the front we chose a 12 volt replica because it looked outrageous and was HUGE!  We may be able to have it double for a windscreen... we'll see if the police agree.  Bulbs were an old style, 2-pin, three hole twist type connector.  About $5 each with halogen replacements for about $18.  We'll wait until we're sure we're not going to burn them up getting the wiring right before we spring for the halogens.

Taillamp

A stock lamp was not going to work... even one of the 12 volt replicas because of the bobbed rear fender.   We bought a replica of something cool... don't know what it was, but it matched the shape of the rear fender so we could tuck it inside and out of the way. 

Wiring

Wiring is an interesting challenge when you have picked parts from a variety of different applications and are only armed with vague ideas about what you want to happen.  Fortunately, we got a great bit of help from Buck at NIGTBEAST@aol.com.  Buck was on Hackasaw's Bike Builder Forum and he provided a great kick-off with a dandy diagram and an offer to work on the magneto should it fail to deliver the right kind of power!  Here's the trick hook-up!

Well the diagram is a great start...  We acquired a new Accel solid-state replacement for a mechanical regulator off a 68-75 Sportster and an Accel battery eliminator...  a lot of Sportster parts are showing up on this bike... It has a tendancy to burn out headlights and taillights so something's not quite right. Will have to figure that out some day.

Voltage Regulator Wiring

The Accel solid-state voltage regulator had only four wires on in... not the five that are in the diagram.  So, we ran the yellow wire from the voltage regulator to the battery eliminator and then to the battery post (3) on the ignition switch.

Use a borrowed battery to polarize your system (the eliminator/capacitor needs to know which way it is being used just like the generator).   Put a charge on the battery eliminator/capacitor (negative on ground and positive on the incoming).  Using a solid state regulator you'll hook everything up and momentarily "flash" (touch) the armature "A" on the generator to the positive post of the battery eliminator/capacitor.  Using a mechanical regulator it is different.  You just flash the Battery terminal on the regulator with the Generator terminal momentarily using a smaller piece of wire.  Be aware that every time you undo your system you'll have to go over this step again.  Otherwise your electricity will flow the wrong direction.   On a generator the power is produced by the Armature terminal and controlled by the Field terminal.

We couldn't decide where to run the wire to the generator signal light.  We finally decided the best place to run it was from the A terminal on the generator directly to the generator light so we would be getting an indication when it was charging.

Wiring Color Code

WLA Wiring Diagram

WL Wiring Diagram and Legend

End Result

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