What's the difference between the two and what does each one do?

If I had a charging system issue, how would I know which one was giving me the problem?

Sorry for the stupid question, but my weakness is in electrical (vs. mechanical) and I want to learn this stuff. Gotta start somewhere...

 

The stator creates the electrical power.
The regulator regulates the electrical power that is supplied to the bikes electronics.

(The stator fills the same role as an alternator on a car)

The following was copied from another post here, I'm a clutz for not remembering who posted it though.

Important information about Harley Davidson full wave charging systems (covering 70-05 Touring, 84-07 XL, 84-00 Softail, 91-03 Dynas, All FXR’s)

1. Battery Test:

The battery needs to be a fully charged battery that has been load tested to ensure proper readings. If you are not working with a fully charged and functional battery, all other voltage tests will be incorrect. Most places like Auto Zone, Advance Auto, and Pep Boys will charge and test motorcycle batteries for free. Standing battery Voltage should be 12.5-13.2 DCV.

2. Charging System Voltage Test:

Start motorcycle, Measure DC Volts across the battery terminals (you should have a reading of approximately 13.2-15 DC Volts).

3. Check Connections/Wires:

Inspect the regulator/stator plug, and check the battery terminals for connection/corrosion. If everything seems to be in order, move on to number 4 below to determine if there’s a failed component.

4. Stator Checks/Rotor Check:

Each of the following tests isolate the stator & Rotor, If AC Output test Fails and Resistance Check, and Stator IB Test Pass then Rotor is at fault (Pull Primary covers and inspect rotor for damage).

AC Output Check:

Unplug the regulator plug from the stator
Start motorcycle and change Voltmeter to AC volts.
Probe both stator wires with your meter leads.
The motorcycle should be putting out approximately 18-20 ACV per 1,000 rpm. (Reading will vary depending on system, check service manual specification)
Generic Specs:

22 amp system produces about 19-26 VAC per 1,000 rpm
32 amp system produces about 16-20 VAC per 1,000 rpm
45 amp system produces about 19-26 VAC per 1,000 rpm

Stator Resistance Check:

Switch your multi meter to Ohm x 1 scale.
Probe each stator wires with meter leads and check resistance on meter.
Resistance should be in the range of 0.1-0.5 Ohms. (Reading will vary depending on system, check service manual for specification)
Generic Specs:

22 amp system produces about 0.2 to 0.4 ohms
32 amp system produces about 0.1 to 0.2 ohms
45 amp system produces about 0.1 to 0.2 ohms

Stator IB test or Ground Check:

Switch your multi meter to Ohm x 1 scale.
Probe each stator wire with your positive lead on multi meter and the negative to ground.
There should be no continuity to ground on either wire.
If there is continuity to ground your stator is shorted to ground.

5. Regulator Test:

Each of the following tests isolates the regulator only, so if any of these tests fail, the regulator is at fault.

Identifying Wires:

Battery Charge Lead- Wire going from regulator to battery positive.
AC output leads- Wires coming from the Stator to regulator.
Ground- Wire from Regulator to ground or regulator may be grounded via the physical bolting to chassis.

- Regulator Ground Test: Insure the regulator body is grounded or grounding wire is fastened tight to a good ground (you should verify this by checking continuity from regulator body to chassis ground).
- Fwd/Reverse Bias Test/Diode Test: This check is testing the Diode function to ensure it is regulating the AC current for the stator into DC Current.

Switch multi meter to Diode Scale.
Place your Multi meter positive lead on each AC output wire.
Place your multi meter negative lead on the battery Charge wire.
The meter should read voltage typically around .5 volts.
Next, switch your multi meter leads putting the negative lead on the AC output wires and the Positive lead on the Battery Charge Wire.
The reading should be Infinite.
With your meter on the same setting, place your multi meter positive lead on the regulator ground wire or to the regulator directly, and then place your meter negative lead on the AC output leads.
The meter should read voltage typically around .5 volts.
Next, switch your multi meter leads putting the negative lead on the regulator ground and the Positive lead on the AC output wires.
The reading should be Infinite.

 

Hoggy,

You didn't mention what your conditions are that causes you to believe it may have an issue.(?)

If you can drain off some primary fluid, or even just open one of the inspection plates and smell the fluid. When a stator goes bad they create a burnt electrical smell similar to a burnt transformer.

The two big issues is often a bad connection involving the battery. Either the connections on the battery or as simple as a loose ground to the frame have given major issues for many Harley owners.

Also if your battery is low, it don't take much, it may not supply enough voltage to the ignition to start, even if it's turning over.

Give us the details of the issue.



duecedog,

Good details!

 

Duecedog put some good troubleshooting info out there but will try to keep it simple for the first heads up of what working with.. Think of a Stator as Stationary or a Field .. Think of a Rotor doing as it's name says and Turning within the field to Generate Electricity .. The Voltage Regulator delivers the Proper Amount of Voltage ..

 

Thanks all. No issues at present. I'm just trying to learn this stuff and how to diagnose if I ever do have an issue. I am going to be tearing into my bike within the next couple weeks for mods and will have to deal with some electrical stuff - re-wires and such. I cringed at the thought of opening up those wiring diagrams at the back of my shop manual and finding a bunch of black lines I could make neither heads nor tales of (intimidated by traditional wiring diagrams), but was pleased to find they were all color-coded and broken up into sections making them much easier to understand.

 

Well.... I was changing my fluids last weekend and I couldn't help but notice that the odor in the air reminded me of burning hemp if you get my drift. Now my charging system is giving me problems. Could the stator have been what I was smelling?

 

Don,

Yep, your nose knows! It's a curse many of us have had.

Be sure to check into what else is wrong in the system. A bad battery can constantly need charging and over heat the system. Too many heavy accessory lights add to the trouble. Often the regulator has issues like a wire shorting to the frame. Or the stator connection being corroded (you'll get a new one attached to a new boot on the new stator).

Have you ever opened up the primary?