Abstract: This invention provides an improvement in a flywheel magneto having a thyristor controlled capacitive ignition system including a flywheel having permanent magnets and at least one cooperating coil core which has three pole legs and at least one charging coil and one trigger coil. The improvement therein comprises a charging coil arranged on the intermediate pole leg of the coil core and a trigger coil being arranged on the last pole leg when viewed in the direction of rotation of the flywheel.

Abstract: For an internal combustion engine, there is provided an electrical power generator system and an electronic ignition system both disposed under the flywheel casing. Permanent magnet means provide a rotating magnetic field for the generating coils of the generator system and the charging coils of the ignition system, there being a separate trigger magnet for creating a magnetic field for a trigger coil of the ignition system. A shielding plate of ferromagnetic material is fixedly disposed between the permanent magnet means and the trigger magnet to shield the trigger coil magnetically from the field of the permanent magnet means whereby it will respond only to the field from the weaker trigger magnet. Preferably, the shielding plate can be angularly adjusted and supports the trigger coil to enable adjustment of timing.