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ok, so i did some research and decided to post here what i have found...
Alternator - has a set of rotating magnets mounted to the crank + a set of coils (usually 3) that surround that rotating assembly. As the magnets pass by the coils, the voltage builds to a positive peak, then goes past 0, then builds to negative peak, then goes past 0 again, effectively creating Alternating Current (AC).
Points - they time the firing of the plug. The point gap regulates how long they will stay open. When they open right before TDC, they disrupt the electro-magnetic field of the alternator, producing a spark. Typically seem to last 2000-8000 miles, depending on age and use.
Ingintion Coil - basicaly an AC Transformer, consisting of primary and secondary windings. Sometimes, switched DC acts like AC as well. In a nutshell, voltage is applied to primary coils and then multiplied and output by the secondary coils, creating higher current.
Condenser - a capacitor that stores electricity, connected across the primary and secondary coils, making the circuit into an oscillator, oscillating the primary voltage and thus increasing the secondary voltage. It also acts as a path to the ground protecting the points from burning up form too much current when they change from closed to open. The capacity of a condenser is measured in microfarads (0.2 microfarads being the average capacity) and that capacity is matched to the points. If there is a big build up of material on one of the points it means the capacity of that condenser is too big or too small for that set of points. If the negative point (grounded or stationary) loses material, with the build-up on the positive (moving) point, then the condenser capacity is too low. If the build up is on the grounded point the capacity is too high.
Rectifier - flips the negative part of the AC electric wave to become positive. Although the current still alternates between 0 and peak, it is all positive, therefore possible to take an average of, thus called Direct Current (DC). Used to charge the battery, prevent discharge from alternator drain when bike is off, and regulate the lights voltage.
Regulator - regulates peak voltage (which is based on rpm) by dumping it to the ground when too much.
Now, apparantly, there are 3 different ignition systems.
1. ETS - Energy Transfer System - works on AC... no rectifier, no regulator, no battery (or cap). Alternator stator is timed to produce max volts at point of crank rotation when sparkplug fires. Timing is critical, as it has a narrow voltage peak, and thus limited timing advance. In ETS points are first closed, routing the generator current to ground, bypassing coil. At firing time, points open, releasing the peak voltage straight from the Alternator to the Ignition Coil. Current flows through the coil for a relatively short time, creating little heat, making it possible to use small-sized coils. Lighting is 6V and uses coil's generating windings. However, lights (esp brakelights) affect idle speed, and a short in lights circuits will kill the engine.
2. BIS - Battery Ignition System - points connect Coil to the Battery. Alternato generates an electro-magnetic field charging the coil when points are closed. At firing time, points open, breaking the field, and creating a spark at the plug. Dwell time here is the ammount of time needed for points to stay closed for complete coil saturation.
3. CDI - Capacitive Discharge Ignition - considered the newer version of ET, no points at all, solid state. When near firing position, Pulse Generator triggers Rectifier that makes Capacitor discharge rapidly, relasing current into the Iginition Coil.
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2000 XR600R
1979 XR200R
1975 MR175 Elsinore
1987 Husqvarna 510TE
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