Charging systems

[Barefoot Choppa]

Charging systems
Charging systems explained to the best of my knowledge. Disclaimer: I am no expert here but have a vast knowledge in electronics and some of this was researched…….so……..here it goes. My contribution to my friends here at BHO, Hope this helps some of ya!!!

Solid State versus Mechanical
Solid state means that there are no moving parts to break. Mechanical regulators have points, (remember them on your ignitions), These point contacts close and open according to electrical needs allowing electricity through or preventing it from flowing onwards. They pit, they burn, they weld together and they always go out of adjustment. What more would you like to know? Well, how about the difference between a regulator and a rectifier? Regulators and Rectifiers these devices are required, in part, because alternators and generators spew out the current which is usually too much for the battery to absorb without a correcting mechanism. Regulators are used on generating systems because they regulate the current from the generator to the battery. Too much current and the battery fluid, (electrolyte), boils from overcharging. Too little current and the battery will not fully charge. They also stop current from flowing back into the battery when at rest whether by opened contact points or a diode. Diodes are solid state do-dads that only allow current to flow in one direction. Regulators alone do not suffice for an alternating system. An additional component is required in order to change the alternating current to direct current. A battery stores direct current only and distributes it to the electrical system. This second function is incorporated into the rectifier that also regulates

Alternating and Direct Current
Direct current generated by generators is exactly as described. It flows only one way. Alternating current alternates between flowing one way and then the other. It goes back and forth equally much like a sine wave, which visually demonstrates the change in voltage and direction of current flow known as polarity. The magnets in rotor cause the current to reverse direction every 180 degrees of rotation. There are 3 ways to increase current, (amperage), in an alternator. The first is to increase the force of the magnetic field. Secondly, more coil windings in the stator will accomplish this while the third is to increase rotation speed, (rpm), of the rotor going around the fixed stator coils.

Amperage
Amperage, (mathematical formulae symbols I or A), is a measurement of current flow. Voltage, (symbols V, or E) is the pressure of the current flow while Ohms, (symbols R or W), is a measurement of resistance to flow. Imagine a river flowing along. Amperage would be the amount of flow. Voltage would be the pressure the flow generates while resistance would be the drag created by the river's bed and banks. Slight drops in current can be precipitated by putting the brakes on thereby activating the brake lights. Larger current drops would occur when starting the bike or turning the headlight on.

Testing Alternators
A voltmeter measure voltage, an ammeter measures current or amps while an ohmmeter measures ohms or resistance. The tool that does all three is called a multi-meter or more precisely a VOM, (volt: ohm: milli-ammeter).
1. Testing the stator: Disconnect the regulator from the stator. This is done by simply pulling the regulator plug where it plugs into the stator receptacle in the front of the left side of the engine casing near the primary. Switch the multimeter to the ohms reading. You will be checking for continuity between either stator pin and the engine crankcase. The pins are exposed when the regulator plug is disconnected. It does not matter which pin is used for the test. Continuity means whether there is a connection, (short), between the stator coils and the engine casing which would be referred to as a ground. Therefore the term, "grounded stator". You touch one multimeter wire to any stator pin and the other wire to the engine casing. There should be no reading if the stator is good. If there is a reading then the stator needs to be replaced. The second stator test is for resistance between the stator pins. Attach one multimeter wire to one pin and the other to another pin. There should be a reading of 0.1 to 0.2 ohms. A lower reading indicates that the stator should be replaced.
2. Testing output: Disconnect the regulator as described above. Set the multi meter to AC volts. Touch the wires to the stator pins while the engine is running at 2000 rpms. There should be a reading on the voltmeter of between 32 and 40 AC volts. The reading will increase or decrease between 16 to 20 AC volts with every engine rpm change of 1000 rpms.
3. Testing Current Draw: Turn everything on. This includes all accessories, ignition, high beam, etc. The multimeter is set on amps. The wires must be connected between battery positive and the positive side from the battery on the key switch. One note, the average multimeter only measures to around 10 amps. With some alternators producing 45 amps this type of multimeter is obviously inadequate. So, the proper reading tool is required. You are really measuring the battery drain. The current draw should be at least 3.5 amps less than what it’s actually rated for. This is also assuming you know what the rating is.

Just thought I’d throw this in here :The enemies that seek to destroy rotors by dislodging magnets are heat, oil and vibration.

Okay, the researched parts off the internet:
Generators
Generators are weighty appendages hanging off the right side engine case. Combined with the extreme vibration spawned by the Ironhead Sportsters in particular and only to a slightly lesser extent of the Big Twin Knucks, Pans and Shovels this system leaves a lot to be desired. Generators on a vibration-free machine with a solid state regulator would last many times longer than on a rock’n’roll Harley. It would even be considered reliable. The second problem with generators on a modern Harley is current output. The demands of EFI plus all the accessories now available would not be well served by the Harley generator system.

Polarizing Generators
Over the years there are few questions asked more often than how to polarize a generator. This is required whenever the battery, regulator or generator is removed or disconnected. If this isn't done then the relay mechanical points will burn out, will cause the battery to drain and go dead or damage the generator. It takes seconds to polarize a generator but many don't take the time. Touch one jumper wire to the positive battery terminal while touching the other end of the jumper wire to the armature (A) terminal on the generator. This method will work on EVERY generator Harley whether there is a solid state or mechanical regulator. If there is a mechanical regulator, an alternative way is to touch one jumper wire to the BAT terminal on the regulator and the other to the "A" terminal on the regulator. The terminals are marked.
On the Bosch regulator used on many Sportsters some stuff is in German. Touch one jumper wire to the BAT terminal and the other to the D+ terminal. The moment this is done the generator is polarized.
Sportster Four Speed Alternator
In 1984, the factory dropped its generator charging system used in various configurations since 1952 for a hopefully longer lasting alternator charging system. The 1970-2002 Big Twin and the 5-speed Sportster from 1991-2002 alternator’s two component parts, the rotor (which rotates around the stator) and the stator (which stays in a fixed position) are located behind the front motor sprocket. On the four-speed Sportster, however, it is located as an integral part in the rear of the clutch hub. All traditional Harley alternator systems are housed on the left side of the bike inside the primary chain cover. As far as cost goes, the stators on both bikes are about the same but the XL rotor is exorbitant in cost. The whole clutch housing must be replaced when there is nothing else wrong with it other than dislodged or damaged magnets Four-speed alternator XL's should change the primary fluid according to the manual and the magnetized drain plug should be checked and then cleaned. Steel particles and very thin slivers are normal as chain-to sprocket wear generates this debris. Chunks of metal are not normal, and are indicators that something is wrong. This bears closer physical examination, as it is usually a warning that repairs are needed. The distance between the rotor and stator is very small, and metal debris in the oil will be attracted to the heavy magnets that make up the rotor. After a while, the debris will build up and possibly bind the two, causing the stator to either short circuit or dislodge the magnets and precipitate all kinds of horror. A worn clutch hub bearing (36799-84) or transmission trap door bearing (9025A) or combination will allow the clutch hub rotor to rock back and forth, eventually letting it touch and then hit the stationary stator bolted to the trap door. These bearing should be changed every four to five years, and certainly checked every 20,000 miles. Make a point of replacing them every time your clutch is repaired. Riding, and in particular, initial acceleration and downshifting techniques can also play a role. The conservative rider need not worry, but those that love to do “hole shots” and downshift hard at high RPMs put extra strain on the clutch hub chain sprocket. These radical sudden pulls combined with worn bearings and metal debris can rock the rotor into the defenseless stator.

Oil Impregnation
Change your primary oil frequently. Oil forms byproduct acids over time, through heat and mechanical interaction of parts. The breakdown of mechanical parts like clutch fibers also forms chemicals like acids, which combined with heat and contraction helps to weaken the adhesives over time Redneck has shown me a chemical cocktail that will allow removal of old magnets from the rotor housing without damaging them or the housing. Furthermore, the magnets and housing will be glass-beaded, washed, and then baked making them virtually free of any oil or contaminants. There is no point in doing many mechanical repairs such as welding or gluing if oil impregnation interferes and bastardizes the process setting up the next failure. We are not trying to glue oil to the magnet or the rotor but magnets to the housing. Oil will not be able to come out of the formerly impregnated metals to work its destruction from within.

[Tailspnr]

Great stuff Rick!!!!