1. Ducati Magnetos with ∅94 ID flywheel
Ducati magneto 31.17.30 for 1974-85 Tomos
Ducati Elettrotechnica Microfarad magnetos, 94mm id flywheel, were on 1974-1985 Tomos (early A3 engine), 1970’s Morini S5K2 (Marina Mobili part number 29-0026), and maybe others.
ZEM magneto 31.17.30 for 1983-1985 Tomos, is identical to Ducati
ZEM magnetos, identical to Ducati, 94mm id flywheel, were on 1983-85 Tomos (A3 engine). ZEM is a remake of DEM (Ducati Elettrotechnica Microfarad), because it is identical.
These magneto-generators are 3-wire external ignition ground type, like most Italian made US-model mopeds. Like many other US-model moped magnetos, the brake light is powered by the ignition source coil ground. This was to meet the US DOT requirement that the headlight not get dim when the brake light was on. So the two-coil generator has three outputs, the black ignition wire from the points to the spark coil, the blue ignition ground wire that is grounded through the brake light or brake light switches, and the yellow light wire the provides 6V AC about 25 watts for light and horn.
Early Tomos 1974 to 1985 had this type of magneto, with the brake light switches wired in series and normally closed when installed. If you removed the tail light and squeeze either brake, the engine would die. Starting in 1986 Tomos improved the electrical system with a solid-state-regulated single lighting yellow wire, a ignition black wire, and an internal ignition ground. So the engine never dies, on a 1986 and later Tomos with the 2-wire Iskra magneto, when the tail light wires are unplugged and the brake is applied. When the magneto type changed from 1985 to 86, the wiring also changed.
These Ducati and ZEM 94mm complete magnetos will interchange with 90mm Bosch complete magnetos and other Bosch compatibles like Iskra, except for the width and position of the key groove that determines the ignition timing. They are counterclockwise rotation. Points are CEV type “right hand” (the brown part looks like your right hand sideways with fingers bent). Condenser is CEV type.
Tomos mopeds have been equipped with many different magneto names and types.
2. Ducati Magnetos with ∅80 ID Flywheel
Ducati magnetos, 80mm id flywheel, were also on 70’s Minarelli manual-shift engines P6 and P6-70. Below is a magneto from a 1974 Indian ME76, Minarelli P6-70 engine, USA street model with a brake light. It has 3 output wires. Similar magnetos for off-road motorcycles or European mopeds without a brake light only have 2 wires. Red wire is ignition (points to spark coil). Black wire is power for lights. Purple wire is power for the brake light (or battery charging if there is a battery).
Ducati 31 12 38 magneto on 1974 Indian ME76
82.0006.6 points Ducati = M14
82.0132.6 condenser Ducati ∅17.9 = M17T = modern M17
82.0181.6 greasing felt Ducati
82.0101.6 cam adjuster CEV MMI 6050
82.0440.6 base plate Ducati
82.0018.6 stator assy Ducati for 31.02.30, 31.02.39
82.0019.6 stator assy Ducati for 31.02.74
82.0036.6 stator assy Ducati for 31.02.77
82.0046.6 stator assy Ducati for 31.12.59
82.0047.6 stator assy Ducati for 31.12.37
82.0212.6 flywheel ⇐ Ducati 31.02.30
82.0214.6 flywheel ⇐ Ducati 31.02.39
82.0215.6 flywheel ⇐ Ducati 31.02.74
82.0231.6 flywheel ⇐ Ducati 31.02.77
82.0245.6 flywheel ⇐ Ducati 31.12.37
82.0252.6 flywheel ⇐ Ducati 31.12.59
minarelli# flywheel stator lights
minarelli# dir id od od wires watts
82.0001.9 ⇒80 103 94 o♦♦ 6V 18/00 Ducati 31.03.61 V1
82.0029.9 ⇒80 103 80 ♦♦ 6V 18/00 Ducati 31.03.73 V1 G1R
82.0012.9 ⇐80 110 94 ♦♦ 6V 18/00 Ducati 31.02.30 P3 P4S P4V W3 =912301?=M16-12?
82.0000.9 ⇐80 110 94 o♦ 0V 00/00 Ducati 31.02.32 P4 kit = M42-208
82.0000.9 ⇐80 110 94 o♦♦ 6V 18/00 Ducati 31.02.37 P4 kit = M42-208
82.0014.9 ⇐80 110 94 ♦♦ 6V 18/00 Ducati 31.02.39 P4 P4V P4E P6 P6/4 P6R W3 =912401
82.0015.9 ⇐80 110 94 ♦♦ 6V 18/00 Ducati 31.02.74 P6 potenza?
82.0000.9 ⇐80 110 94 ♦♦♦ 6V 25/10 Ducati 31.12.38 P4S-US P6CS-US
82.0031.9 ⇐80 110 94 ♦♦ 6V 18? 0 Ducati 31.02.77 P4? P6?
82.0046.9 ⇐80 110 94 ♦♦ 6V 00/00 Ducati 31.12.54 P3?
82.0045.9 ⇐80 110 94 ♦♦ 6V 00/00 Ducati 31.12.37 P4? P6?
82.0052.9 ⇐80 110 94 ♦♦ 6V 00/00 Ducati 31.12.59 P3? P4? P6?
