® Charging System Variations
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Many don't realize how many variations on the simple theme of charging the battery there are in the motorcycle world. Following are the major differences between charging systems. Fortunately, though it seems there is a confusing array, in reality, it can all be reduced to just two basic systems -- permanent magnet and electromagnet.

Diagram System Type Vehicles Using Description
British DC Generator Triumph, BSA, Norton and others through the 1960s One of the earliest motorcycle charging systems. Note the positive ground.
Euro DC Generator Moto Guzzi & BMW through the 1970s Identical to the British example except for the negative ground.
Harley-Davidson DC Generator Harley-Davidson Big Twins through 1969, Sportsters through 1984 Very similar to the Euro DC generator, except that the regulator is self-grounding.
Early Half-Phase, Permanent Magnet Alternator Off-road machines, very small bikes and scoooters Some examples did not have a regulator but relied on the loads themselves to keep output in check.
Later Half-Phase, Permanent Magnet Alternator Later small motorcycles A later, improved version of the previous system, wherein the regulator is incorporated into the same housing as the rectifier.
British Single-Phase Permanent Magnet Alternator Triumph, BSA, Norton and others from mid-1960s through end of pushrod era (1980s) Dual voltage control -- a switch-able stator, and a zener diode regulator. The zener was simply a resistive short across the battery that automatically turned on at a preset voltage.
Early Non-Brit Single-Phase Permanent Magnet Alternator Asian and Euro twin-cylinder machines through the 1970s (CB350, CB450, etc.) The Asian version of the switch-able stator system, with the notable improvement being the use of an SCR based regulator that shorted the stator instead of the battery.
Later Non-Brit Single-Phase, Permanent Magnet Alternator Honda CB/CM250, smaller Polaris ATVs More modern version of the single phase system, with the regulator incorporated into the same housing as the rectifier.
Early Three-Phase, Electromagnet Alternator Medium to large Asian multicylinder bikes (CB750, CB550, etc.) to about 1975 Long the traditional alternator, this one continues today in the more modern form shown below.
Later Three-Phase, Electromagnet Alternator Large Asian bikes after about 1975 (CB750 Auto, other Honda fours) More modern version of the three phase electromagnet system.
Early Three-Phase, Permanent Magnet Alternator Four-cylinder Honda Gold Wing through 1979, KZ900 Permanent magnet version of the three-phase alternator
Later Three-Phase, Permanent Magnet Alternator Four-cylinder Wings after 1979, CBRs, ZXs (in fact nearly all Kawasakis including ATVs and watercraft), GSXRs, later Ducatis. The most common system in the powersports industry at present. More modern version of the three phase permanent magnet system.
Three-Phase Integral Alternator Six-cylinder Gold Wings, Suzuki Katanas, a few Kawasaki models (early Concours, Diesel Mule, ZR1200, ZRX1200R) Uncommon, very automotive design, fully self-contained

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