One defective ignition unit can sometimes cause the entire ignition system to be inoperative. In this case, the trouble can be located without test equipment.


A.     Disconnect the three light green wires going from the ignition rectifier unit to the ignition units.


B.     Connect one wire at a time to its ignition, unit and check the spark for that cylinder.


If two of the cylinders will spark when connected alone, the ignition unit for the non-sparking cylinder is bad.


Make sure the spark plug in the non-sparking cylinder is good.


Proceeding from that point, there are only four possible places for the trouble to be: the coil, the ignition unit, the ignition rectifier unit, or the signal generator.



By following the steps below it will be easy to pinpoint the defective part.

"BC" means bad cylinder. "GC" means good cylinder (either one of the remaining two).


I.          (a) There are three light green wires coming from the ignition rectifier unit, and one goes to each ignition unit. Take the two of these, which go to the BC ignition unit and the GC ignition unit and reverse them.


(b) Check the spark for two cylinders. If the trouble has shifted from the BC to the GC, the ignition rectifier unit is bad. If the trouble remains in the BC, go to step two.


II.       (a) Reverse the BC and GC plug wires so the BC wire goes to GC plug.


         (b) There are three red wires, one from each ignition unit to each coil.  Reverse the BC and GC red wires.  This can be done at either the junction near the coil or near the ignition unit.


         (c) Now check the spark for both cylinders.  If the trouble has switched to the GC, the BG ignition coil is bad.  If the trouble is still in the BC, go on to the next step.


III.     (a) Return the spark wires back to normal, but leave the red wires reversed.


(b) Each ignition unit has a white wire coming from it.  Reverse the   BC unit and the GC unit white wires.


         Once the defective part has been located, return all wiring to normal.



CAUTION:  Battery failure is not considered as a possible source of ignition trouble since the motorcycle will start and run without the battery.  However, running without the battery will eventually cause failure of the ignition units.





There are few components that make up the ignition system. All can be easily tested with an ohm meter except the CDI boxes . If you don't have one, get a cheap ANALOG meter from Walmart or such for about $10.

- CDI boxes - must have ground wire attached to good frame ground.
- Kill switch - on RH grip asm - must be in "RUN" position.
- Hi/Lo speed coils - located in stator - unplug the three pin connector between the stator and the CDI unit with wht/grn/blu wires. Test between the blu & white wires of the plug going to the stator. It should be 180-200 ohms. There should be an infinity reading from any of those wires to ground.
- Pickups - located under LH engine cover - Unplug each of three wht wires between the stator and CDI box. Each should measure 180-200 ohms to ground on the leads to the stator.
- Ignition Rotor - located on end of rotor. Air gap between the pickups and rotor should be .020-.030". H1D & H2 rotors will not interchange.
- Ignition coils - must have mounting to unpainted frame ground. Measure between plug cap and ground... should be about 4.5K ohms. Coil(+) (red wire) to ground should measure 0.8 ohms (near short).

Those are the only components making up the ignition system. No battery is required, nor are any charging components, to get a spark. However, a bad regulator/rectifier can cause rev limiting.