Heres some tech info I found....
REGULATOR/RECTIFIER- The stock XS650 regulator/rectifier will not work with a permanent magnet alternator. Luckily, the majority of bikes made in the last three decades use a three phase permanent magnet alternator. That means there are more potential donors than I can possibly list. Even though used parts are plentiful, they can be the hardest part to spot. All regulator/rectifiers look the same, just a finned metal box with wires coming out of it.
If you know what bike the reg/rec came from then you can search for a picture of the stator used on that bike. What I've done is type "stator"and the make and model of the bike into a Google Image search. If the stator looks like the one above [18 poles] then the reg/rec is for a three phase permanent magnet alternator.
If you don't know what bike the reg/rec came from then you can still identify it by the wires coming out of it. Count the number of different color wires coming out of the reg/rec.
- 3 Colors- The most basic reg/rec has five wires. Three input wires and two output wires. The three input wires hook to the stator and will all be the same color. Like the stator, these wires are usually white or yellow. The two output wires are positive and negative. The positive wire is usually red and the negative wire is usually black or green.
Some reg/recs have seven wires. Three input, and four output. These are the same as the five wire units except that they have two positive wires and two negative wires. They do this because two wires and connectors can more reliably carry the current than a single wire and connector. Both the positive wires will be the same color, and both of the negative wires will be the same color.
- 4 Colors- Many permanent magnet reg/recs have an additional voltage sensing wire. Usually orange, brown or black. This wire is hooked to the ignition switch to get power when the switch is turned on. If you aren't running a battery then you can hook it to the positive wire and the reg/rec will operate the same as a standard five wire unit.
If there are more than four different colors then it may or may not be a regulator/rectifier for a permanent magnet alternator. You will need to know what bike it came from and check a schematic to find out what the additional wires are for. Regulator/rectifiers are plentiful so if you're not sure about one then pass on it and buy one you know will work.
