SOHC4 Electronic Regulator Replacement from http://forums.sohc4.net/
Pinhead:
I started a thread a THREAD way back in '06 about how to replace the expensive electronic regulator/rectifier and the old mechanical regulator with a modern automotive equivalent. At that time I used a Ford regulator since that was what I had on hand - and it was CHEAP.
I've since reconsidered my choice. Six years and almost 400 posts later I've decided to use a VR295, commonly used by Dodge. It only has two terminals (and a case-ground) so there aren't unused connections to get confused.
VR295 Diagram.jpg (49.02 kB, 530x503 - viewed 217 times.)
Attached is the picture and a diagram. I hope this will be much less confusing so more people can save themselves some money and a lot of headache. This should work on all of Honda's field-regulated alternators. It wouldn't work on the permanent magnet alternators, but should work on any of Honda's three-phase systems that has a center coil, whether it's a coil on the side cover or an electromagnet coil on the crank end. (500, 550, 650, 750, 900 1000, 1100, and probably more) EDIT: The color codes don't coincide with any wiring codes on the motorcycles. EDIT 5/30/2013: This regulator draws 10ma when idle with the key off. If you ride your bike every day or every other day, this shouldn't be a problem. However, extended periods of non-use will eventually drain the battery. Therefore I recommend feeding the "sense" wire through a relay. This could also be accomplished by tying both terminals together and running a single wire to a relay, as in the second diagram. A VR124 regulator will work as well. I don't have wiring color codes yet, though.
VR295 Diagram.jpg (49.02 kB, 530x503 - viewed 217 times.)Attached is the picture and a diagram. I hope this will be much less confusing so more people can save themselves some money and a lot of headache. This should work on all of Honda's field-regulated alternators. It wouldn't work on the permanent magnet alternators, but should work on any of Honda's three-phase systems that has a center coil, whether it's a coil on the side cover or an electromagnet coil on the crank end. (500, 550, 650, 750, 900 1000, 1100, and probably more) EDIT: The color codes don't coincide with any wiring codes on the motorcycles. EDIT 5/30/2013: This regulator draws 10ma when idle with the key off. If you ride your bike every day or every other day, this shouldn't be a problem. However, extended periods of non-use will eventually drain the battery. Therefore I recommend feeding the "sense" wire through a relay. This could also be accomplished by tying both terminals together and running a single wire to a relay, as in the second diagram. A VR124 regulator will work as well. I don't have wiring color codes yet, though.
VR295.JPG (12.37 kB, 400x300 - viewed 142 times.) Relay'd Regulator.jpg (52.4 kB, 468x578 - viewed 243 times.)
RECTIFIER REPLACEMENT
The three-phase charging system that we have requires a three-phase rectifier which isn't included in the aforementioned regulator. Luckily it's simple enough to use a generic three-phase rectifier. Any three-phase rectifier will work as long as it can handle 35 or so amps and has a minimum peak-inverse-voltage of 24 volts. Most bridge rectifiers have PIV ratings at 100 volts or higher (mine is rated at 1000v) so you shouldn't have any trouble finding one that is suitable. The rectifier must be heatsinked. I mounted mine to a solid piece of angle-iron that extends the width of the frame (my ignition is also mounted to this) so there is substantial mass through which the heat can spread.
Wiring the rectifier is a lot simpler than it looks. The three wires that come out of the alternator are three-phase AC power. The rectifier will convert this power to DC.
Just to make it simple, I'll use the three-phase rectifier from above as an example. Three of the lugs will be labeled with a "~" which denotes AC power. The output of your alternator goes directly to these three lugs. The "-" lug goes to the "-" terminal of your battery and the "+" goes to the positive terminal. Since the regulator varies the output directly from the alternator, this is all you need to do with the rectifier.
Rectifier.jpg (47.56 kB, 639x578 - viewed 188 times.) Generic Rectifier.gif (7.18 kB, 509x287 - viewed 171 times.)