Regulator/rectifier problems are pretty common with the 'Hawk. There is tons of info available on that subject here and elsewhere on the net.

My battery ('98) did the same thing, and I thought something was pulling it down.... but it turned out to just be the battery. Eventually, if I turned it off and let it sit for more than a couple of hours, it would lose most of its charge. I think my new battery was $40 at Wal-mart. You can always take your battery to Pep Boys or AutoZone or somewhere like that and leave it with them so they can check it. Good luck.

 

You need something to keep the battery charged or it will lose its charge and die. This is the job of the alternator. The alternator produces electricity and delivers this electricity to the battery and maintains a full charge at all times. If the voltage produced by the alternator goes above 13.5 - 14.5 volts, the battery will be ruined very quickly. It's the job of the voltage regulator to keep the output voltage between the 13.5 - 14.5 volt range.

An alternator is the device used to produce the electricity the car needs to run and to keep the battery charged. The alternator uses the principle of electromagnetic induction to produce voltage and current.

The four main parts of the alternator are the Rotor, Stator, Diode Pack, Voltage Regulator and an Ammeter or Indicator Light to inform the driver of any problems. All of these parts must be in good working order for the alternator to do its job. Let's take a look at each of these parts and what they do.

The rotor is basically a magnet that rotates inside thousands of loops of copper wire wound around a core of iron. This wire wrapped iron core is the stator. As the rotor spins inside the stator the magnetic lines of force cut through the copper wire inducing a voltage. This is the voltage that will go to the battery.

The only problem is this produces AC current and cars/motorcycles run on DC current. So we need something that will convert the AC current to DC current. This is the job of the diode pack. A diode is an electrical one-way check valve that will let current flow in only one direction. The typical diode pack uses four diodes to accomplish this. AC current is feed in on one side of the diode pack and DC current comes out the other side. The diode pack also works the dash ammeter or indicator light.

Now that we have a DC current that the motor/battery can use, we need a way to control that current. That is the job of the voltage regulator. As the name implies, it regulates the voltage going to the battery. It does this by turning current to the field (stator) terminal of the alternator on and off. If the battery voltage goes below 13.5 volts, the voltage regulator sends current to the field terminal and allows the alternator to start charging. Current will then flow into the battery and bring it up to full charge. If the voltage goes above 14.5 volts, the voltage regulator shuts off the current to the field terminal and keeps the battery from overcharging and cooking itself. This is how the voltage regulator controls the alternator output.

When you first start your car, the alternator needs some current to start working. The voltage regulator supplies this current to the field (stator) terminal of the alternator to get it started.

The state of charge of the battery controls the alternators amperage output. When the battery has a full charge, the electro-motive force of the voltage lowers the amperage to almost zero. As the battery charge wears down, the electro-motive force is not enough to stop the amperage, so it flows into the battery and charges it again.

As you use more electrical accessories, such as lights, heater etc., the electro-motive force decreases and more amperage flows into the battery to compensate for the added load. It is extremely important that when alternator efficiency is checked, both voltage and amperage outputs are checked. Each alternator has a rated amperage output depending on the electrical requirements of the vehicle.

In modern alternators, the voltage regulator and diode pack are inside the alternator and are not serviceable by most DIY's and mechanics.

If any one of these parts goes bad, the whole alternator assembly needs to be replaced.

Testing the alternator is simple and basic. You need to check the voltage and amperage output. The voltage is easy enough to check with a voltmeter. If the voltage is between 13.5 and 14.5, it's a good bet the alternator is good. To check the amperage output, you'll need some special equipment. You'll need an ammeter and a load tester to check the amperage.

When the alternator is load tested, a simulated load, usually ½ the Cold Cranking Amperage rating of the battery is applied to the charging system. Then the engine is run at 2200 to 2500 rpm and the amperage is read on the ammeter. The reading should be close to or at the rated amperage of the alternator. If it is, then it's good. If it's substantially lower, then it is weak and should be replaced.

There are some signs you can look for that will indicate a problem with the charging system. If the headlights brighten or the Radiator fan motor picks up speed when you rev the engine, you may have a weak battery. This indicates the battery may not be holding enough current to run the car and is working off the alternator. If the charge light is on dimly at idle, this could indicate a weak alternator. If all the warning lights come on while driving, this could indicate a bad diode pack in the alternator. It may or may not still be charging, but you don't know unless you have it checked. At any rate, it will need to be replaced.

If you notice a strong sulfur smell, it could indicate a bad voltage regulator. The battery acid boiling inside the battery is causing the smell. This could lead to a battery explosion so be very careful when checking it.

Today's charging systems have come a long way and are very reliable. A new alternator can last seven to ten years and a rebuilt alternator can last five or more years. It's a good idea to have the system checked when you have the vehicle serviced at every 30,000 miles to make sure it is in good shape and it will greatly reduce your chances of getting stuck with a dead battery.

 

muaddib,

I had my battery die (while riding) due to a bad R/R over this past summer. You should check out this site....

http://www.electrexusa.com/04_Technical_Start.html

They have some pretty good trouble shooting guides for you to follow regarding charging/electrical systems for motorcycles. Also, if you have the Honda service manual, that would be a good place to look as well.

I used both to figure out what was up with my hawk. The Electrex site info gives very good general info about the systems in general, while the Honda manual is a bit more abstract from what I remembered, but was good to find out "exact" specs about the electric system.

It sounds like your just not getting enough charge from the bike anymore, could be something as simple as a corroded/loose wire somewhere. I'd check the simple first.

J.

 

New link
http://www.electrosport.com/electros...t_finding.html

 

I have a question on those directions. I have the exact same problem. Went through, I have like 12.5 volts at 2500rpm. Which I already realized since it wasn't recharging... Then I don't know where to reach my stator at so I skipped to the regulator/rectifier. In the steps it says: "connect the RED multimeter lead to the red output wire of the RR, connect the BLACK multimeter to the yellow wire. " When doing this I get 3 readings of OL. Next I switch it and get three readings of around .5v... Next step is black on the negative output wire: GREEN and put red on the yellows. I get two OL's and the third I get a reading that goes up to 2.0V then back to OL... I'm assuming this means my r/r is bad... can anyone confirm this?