Can you run with TWO regulators?

[willie]

The PO of my '79 550 just responded to my email re: what components he replaced by saying that he replaced both the stator and the rectifier. Thats great to learn except he spliced one of the wires coming from the rectifier he replaced to go to the OEM regulator. Thats correct according to the schematic. However, iIn this evening's email he stated that the rectifier he installed was a combo unit (ie. regulator/rectifier). Now you understand the info behind the title of this post. What will happen, if anything, if I leave it wired as is AND is there any way to tell if the item he installed is indeed a combo reg/rectifier? There are no markings on it at all.
Thanks,
Willie

[almarconi]

The voltage coming from the stator is AC, when it leaves the r/r it should be approx 12 volts DC. Take a multimeter and measure it.

Get a wiring diagram for your bike and unf*^k your wiring. Last thing you want is your bike on fire because of some shoddy wiring done by the PO. The bike was designed with either a separate regulator and rectifier OR a later model r/r can be installed.

[posplayr]

The PO of my '79 550 just responded to my email re: what components he replaced by saying that he replaced both the stator and the rectifier. Thats great to learn except he spliced one of the wires coming from the rectifier he replaced to go to the OEM regulator. Thats correct according to the schematic. However, iIn this evening's email he stated that the rectifier he installed was a combo unit (ie. regulator/rectifier). Now you understand the info behind the title of this post. What will happen, if anything, if I leave it wired as is AND is there any way to tell if the item he installed is indeed a combo reg/rectifier? There are no markings on it at all.
Thanks,
Willie

If done properly, it might work but this installation sounds more like conincidental opprotunity, rather than an engineered solution. I would go back to a single combined R/R as recommended.

[bwringer]

Sometimes it's just too tough to remove the old R/R, especially the ones mounted under the battery box. Was one of the old components "abandoned in place"? Is it still wired in somehow?

[willie]

Sometimes it's just too tough to remove the old R/R, especially the ones mounted under the battery box. Was one of the old components "abandoned in place"? Is it still wired in somehow?

It appears that the OEM rectifier was mounted behind the battery box, the same location as the PO mounted the new unit. The original regulator is mounted on the opposite side of the bike as the battery box, slightly above and to the right of the fuse box. I spoke with the PO and he didn't have any explanation as to why he spliced into one of the wires to connect (include) the original regulator in the new setup. He assured me that the new component was a combined reg/rectifier.
Now, FWIW, I measured battery voltage before starting (approx 13.0) and running at 4K+ RPM where it rises to aaround 14. I'm tempted to cut the wire to the OEM regulator and check the voltage again. Thoughts?
Willie

[bwringer]

Actually, it sounds like it's working fine.

Button it up and forget you ever saw anything...










Buuuuut, if you just can't stand it, then look at the colors of the wires going into the "new" regulator/rectifier, and see whether it makes sense.

To be honest, we don't have nearly enough info to picture exactly how things are wired on your bike and understand whether it's OK. The old components might still be in place, but you're going to have to physically chase down the wiring and probably unwrap a bunch of old electrical tape to determine what's actually hooked up to what.

How many wires are hooked up to what and what color are they? Keep in mind that some of the wiring might have been added -- the colors we need are the ones from the wiring harness.

Some aftermarket R/R units have five wires -- three from the stator (usually all yellow), a red positive DC wire, and a black ground wire.

Some, such as the common Honda R/R replacements, have six wires -- three yellow stator wires, one red pos, a GREEN ground wire, and a black sense wire that goes to a switched positive (this is the sense wire).

Photos might help, too.

[willie]

How many wires are hooked up to what and what color are they? Keep in mind that some of the wiring might have been added -- the colors we need are the ones from the wiring harness.
Some aftermarket R/R units have five wires -- three from the stator (usually all yellow), a red positive DC wire, and a black ground wire.
Photos might help, too.

Okay, here's what I've got. There are 3 yellow, 1 red and 1 black wire coming off the r/r. The red wire goes to the main fuse box. The black wire now goes to a battery ground. Previously, it went to an air box lid screw. FWIW, the red wire connection to the metal clip that holds the fuse had gotten so hot at some point that it melted the solder and the surrounding plastic. The end cap on the fuse separated from the glass tube when I pulled the fuse.
Of the 3 yellow wires: 1 goes to a white/red wire in the harness, 1 goes to the stator and one goes to the stator also however the PO spliced an additional wire to that yellow wire and connected that to the OEM regulator.
There are 3 wires coming from the replacement stator. All are white. 2 wires connect to the r/r as described above with one spliced to go to the r/r and regulator. The 3rd white wire connects to a white w/green tracer that originates in the harness.
I've also attached a picture of the wiring.
Again, I appreciate any and all advice regarding what I've got and whether or not I should cut the wire going to the OEM regulator.
Willie