Ignition

In the stock H series systems, street biker and H racers, pickup (signal generator) gap is vital to get the ignition curve dialed in correctly. As the signal changes in both time and strength, components in the ignition boxes read the changes, and change the timing

Early Yamaha TZ and some other racing engines use a set of coils to do what this system does, in an energy transfer type trigger, and they are significantly more critical on the rotor to stator yoke gaps. Those systems are set up much like the one in the pictures here.

What I am going to try to build for Hurleys H1R, is a Yamaha based setup with 3 charge coils, 3 signal generators, 3 separate motocross single cylinder boxes and 3 coils. this will give 3 separate ignition systems for the engine, with one curve for the lot. Built from an early TZ250, but with a 3rd set of charge and pickup coils.

The later Yamaha TZ systems use a different stator, one box with one firing system, and two coils, with one signal generator and a rotor with two timing projectors (tips). This system fires both cylinders twice per revolution. Suzuki did something like this for the TR750 in its last incarnation, firing all 3 cylinders, 3 times per revolution, 9 sparks in all.

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