There is no stock way to tie anything into the system to regulate/isolate the charge to the gel battery for a 3 brush generator. There is a way to retain the stock look of the generator and cutout and almost keep the non-stock parts out of view for a 32E converted to a 2 brush. I converted my 32E to 2 brush regulated operation in a unique way that does not require removing the generator, re-wiring the generator’s field windings or changing any of the stock wiring. First I will describe what I did then the usual disclaimers.
1) Read the steps carefully to get the idea of how this is done.
2) Purchase a 6V solid state regulator and mount it under the left foot board. Make sure the voltage regulator is solidly mounted where it has a good ground connection back to the engine.
3) Remove the generator end cover.
4) Remove the third brush leaving the third brush carrier and wires exactly where they are.
5) Drill a 3/8” hole in the generator cover so you can feed two wires from the voltage regulator mounted under the foot board to inside the generator. If you drill the hole in the right place it will not be obvious there are two wires running into the generator. Dress the hole so it doesn’t cut the wires and can be sealed to prevent water from getting in.
6) The voltage regulator’s armature wire goes through the cover and attaches to the positive brush terminal on the generator.
7) The voltage regulator’s field wire goes through the cover and attaches to the third brush terminal on the generator. It is recommended to put an in line fuse of about 3 amps in series with this wire but it is not necessary.
8) The voltage regulator’s battery wire is not used. Dress this wire so there is no exposed copper and fasten it under the foot board out of sight.
9) Put the generator end cover back on and seal the hole where the wires pass through. Make sure the wires are not in contact with the armature.
The 32E is now a regulated 2 brush generator and uses the cutout as it did before. Here are the caveats with this setup:
1) It is not stock but from 5 feet away it looks stock.
2) There is no current protection for the generator that most voltage regulators provide. It will act the same as the Harley 2 unit voltage regulators used on 6V Panheads. If you converted the 32E to a 2 brush generator per “Shope Dope #418” the voltage regulator used (P/N 74511-41) limits the generator current to somewhere around 12 to 13 amps. Therefore Harley must have felt the 32E can safely sustain 12 to 13 amps. If you have a stock electrical load this will not be a problem since the 32E as a 3 brush should be setup for a maximum output of 7 ½ amps when the lights are turned on.
3) If you have a mechanical cutout the voltage will be slightly above 7.2V, maybe closer to 8V. If you have a solid state cutout the voltage will be exactly where it should be.
What you will get with this setup:
1) A regulated 2 brush generator that will appear as a stock 3 brush setup unless one looks closely under the left foot board.
2) The ability to go back to a 3 brush setup by removing the regulator’s two wires and placing the 3rd brush back in its holder. Think about this for a minute……you are on a long trip and your voltage regulator dies. No problem, remove the generator end cover, disconnect the two voltage regulator wires and put the 3rd brush back in. You’re back on the road as if you never installed the regulator.
3) Better lighting with a consistent voltage.
4) Longer battery life since the voltage is regulated.
5) The ability to add some additional lighting such as bullet lights. The 32E as a 3 brush is not designed for any lighting above the stock lighting load of the headlight, taillight and speedometer light. When the 32E is a 3 brush generator and setup correctly it is adjusted for an output of 4 amps with the lights off. When the lights are turned the generator’s output is boosted by 3 ½ amps. That extra 3 ½ amps is just enough to supply the headlight, taillight and speedometer light. Any extra lighting loads will exceed the 3 ½ amp lighting boost and will rely on the battery to supplement the extra current required. This worked fine for the times as long as the extra lights were not excessive and the night ride wasn’t from dusk to dawn. With this setup there are roughly 6 amps left over for extra lights.
Spotlights were always a problem and will still be. Spotlights use around 8 amps of current. Even on a good day this is more than the 32E can handle as a 3 brush and as a 2 brush with the standard lighting. Running with the spots on continually will eventually discharge the battery and cause the 32E to get hot, maybe even throwing solder or burning out windings. There is way around this but that is another subject I am still working with.
Now for the disclaimers:
1) I have only done this on my 45 with a 32E generator. Here are the electrical specs for my 45:
- I have a solid state cutout.
- A lead acid battery that is a 12V battery cut in half to make a 6 V battery. I use an inexpensive WalMart 12V battery that once cut is dimensionally equal to the size of the 6V battery box.
- Two bullet lights on the rear.
- Modified spotlights for reduced current draw that are wired to go on only with the low beam.
I ride with the lights on and high beam all the time, even in the day time, and never had the battery go dead.
2) Know your electrical loads. Since there is no current protection do not exceed the current capability of the 32E as a 2 brush (approximately 12 to 13 amps). It is not even wise to run any generator to its maximum output continually. Figure each bullet light adds an extra amp so it should be safe to run two bullet lights bringing the max load with the lights on to 9 to 10 amps. This leaves a little bit of margin.
3) Never run with a low battery. This is a general rule for the 32E as a 3 brush and also as a 2 brush. Charging a discharged battery or a battery that is not healthy will cause the generator to get hot. This can cause solder to melt and windings to burn up.
4) I am still on the fence about using a sealed battery, even with a regulated 2 brush setup.
This is a regular runner racking up 29,000 miles in 6 years. I have no other data since I am the only one I know of using this setup therefore this is only a sample of 1. You’re results may vary from “it works great”, “what a stupid idea”, “I burned up my generator”, “I fried my electrical system”, etc. If you are adventurous and try this setup I hope it works for you as well as it does for me.


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