How do I test a voltage regulator on a 1976 XLCH sportster with a mechanical voltage regulator?

Question

I just had the the generator on my 1976 sporty rebuilt yesterday I put it on today and its not charging my battery could it be the voltage regulator? How do i know? What do I do to solve this and or how do I test the voltage regulator?

Answer 1

Herb is right. You need to flash (polarize) the generator.

Just run a jumper wire between the "Bat" and "Gen" terminals on the regulator.

(Alternately you can jump from the pos + battery terminal to the terminal on the generator that's labled "A")

Just touch the jumper wire for a second; you should hear a "click" in the generator when you do it.

That's all there is to it.

If you're still using the mechanical voltage regulator I'd suggest changing to a Cycle Electric solid state regulator. The solid state regulator works much better and it's possible for the contacts on the old mechanical regulators to weld together and burn up your battery and wiring. (it doesn't happen often, but it can happen.) Also, often the problem on those mechanical regulators was the ground. Check the nuts that secure it to the bike and make sure there's no corrosion between the regulator and the nut.

The procedure for checking and adjusting the regulator depends on weather you have a Bosch or Delco-Remy regulator and describing the procedure is beyond what I could post here. (it's five pages in the Clymer manual.)

Flash the generator and see if it starts charging. If it doesn't, then get a Clymer manual or factory service manual and a Cycle Electric solid state regulator.(the one that mounts to the end of the generator is best.) http://www.dragspecialties.com/fatbook/7/443/5943772



BTW, those alternator conversions have a tendency to wipe out cam chests on Ironheads. I don't recommend them.

Answer 2

Mechanical Voltage Regulator

Answer 3

First off I am going to recommend that you buy a shop manual for this bike, it will come in handy for repairs and maintenance. Another reason that I recommend you work with a shop manual is, and I apologize that I'm stretching my memory back on this, I seem to recall that there were some things that when working on that bike are not done in an intuitive way. One of the items that I seem to remember is that when you install a new generator on that motorcycle it must be "polarized" by a specific procedure.

Sorry I could not be of more help, I hope you get it straightened out and go riding.

Answer 4

switch to an electronic regulator, The points on that regulator can be adjusted but just switch to electronic.If you can afford a alternator conversion for 500 dollars you should.I have a 76 sporty and had many carging system problems untill I got the conversion