Topic: Voltage regulator question

[Scott S]

The P.O. of our CB400F installed a Ford or Mopar or something voltage regulator. Like, $12 from NAPA. I'm sure you will appreciate his ingenuity, but it basically made everything under the seat useless. It's also impossible to even change the air filter without tools AND he used a bracket that's spot welded onto the air filter itself to put some bolts through. Replacement filters don't have that bracket.
 
 We've sourced the correct air box parts. I also have a used regulator in my parts pile....regular Honda 3 wire... black, green, white. The only way to really test them is to plug it in and see if it regulates, right?
 
The stock harness is uncut. It appears he used the black wire and white wire to plug into the auto parts unit. Then ran a red (power?) wire .... it looks like it's spliced into the black/white stripe power wire...and a green ground/negative wire. Poor ground at that.  Pic is attached. I should be able to plug in the correct unit, crank the bike, rev it up and check voltage on the trickle charger pig tail and, as long as it doesn't get over 15 volts or under ( what's too low?), I'm good to go, right?



 Here's under the side cover. It looks like he has the former green ground wire and a second green ground wire from hooked together and then bolted to the frame. One green wire will plug back into the regulator. I'll have to find out where the other is coming from and where it used to plug in.
 

 

[scottly]

That is a Ford regulator; it's case needs to be grounded, and it also requires a direct connection to the battery. Since the PO didn't hack the harness, it should be a simple job to re-install a stock reg. There is an extra green wire on all these bikes in that area; the logic is to be able to use a three terminal flasher.
The regulator should limit the voltage to 14.5 volts max. Be aware that a digital meter will give erratic readings with the stock reg, as they take "snapshots" of the voltage; you should use an analog meter which will average out the voltage.

[Scott S]

 Sweet! So, I can just safely cap off the end of the power wire, remove the extra ground wire he installed, leave the extra green wire under the LH cover loose, plug in my regulator and see what happens.

[Scott S]

 For the initial test, I can just leave the Ford regulator hooked up to the power and additional ground (his ground wire goes to the negative terminal of the battery), in case my regulator is bad and I need to temporarily plug the Ford reg. back up, right?
 It won't hurt anything to have power to the Ford reg. but not have the black and white Honda wires hooked up, will it?

[Scott S]

 Ah, yes....everything back just as Soichiro intended.

[scottly]