Post Master General
Join Date: Apr 2012
Location: Bowling Green, VA
I Ride: '09 ZX6R
The alternator puts out AC voltage, at a higher level than needed so it can always be cut down to what is required. The bike's electrical system runs on DC. The rectifier converts that High AC voltage to a higher than needed DC voltage, but not by a stupid high amount. Typically, around 15 VDC. This is because you have to have a higher voltage than what the battery potential is, to force a charge into it. Like trying to blow air into a balloon.
If that DC voltage is too high, the battery can get blown up/burnt out. 15 VDC+ will do it.
The regulator portion of the R/R acts like a waste gate or a dump valve, and is supposed to get rid of the extra power from the alternator, leaving the maximum that the battery can take in. That's why you should never see more than 14.3 VDC or so -- the regulator should not allow the voltage to go any higher. (The numbers vary very slightly because all meters are not created equal.) The regulator controls the voltage by shorting out the DC voltage as long as it is above the value it wants to regulate at. That part time short circuit is either controlled with an internal (to the R/R) relay or by a solid state device that does the same thing. That's another connection on the R/R..... you have to have a wire that goes either to the frame, or back to the negative terminal of the battery for that 'dumped' power to flow on. There has to be a complete path all the way back to the battery for that.
If the R/R was smoking and leaking stuff, that means it was getting much too hot and that can only happen if you wired it up backwards, or don't have that ground wire in place.
One side of the R/R is supposed to plug into the alternator out put, the other side should face the battery and the rest of the electrical system. 57-75 VAC where 12 VDC is supposed to be would definitely burn out head lights....... simple check is to put your meter in AC V, and check across the battery with the bike running.
"Basic stuff fellas. Use your head for something other than to break your next fall."