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.