Also earthing is very , very important.
Most people recommend a secondary earth wire from the ignition backing plate to the ignition coil.
Certainly a fabulous product
The following is from the PVL installation instructions.
Section 7: SPARK PLUGS: For an analog PVL ignition, it is not necessary to use resistor type spark plugs or resistor spark plug caps unless you are using some sort of microprocessor controlled data acquisition equipment such as a digital tachometer or exhaust gas temperature gauges. If you must use some sort of RFI suppression equipment, use only resistor plugs or resistor plug caps – never both!
For an Analog version PVL ignition, we recommend using non-resistor fine wire or fine wire/precious metal type spark plugs, such as NGK brand plugs V or VX. These spark plugs, like non-resistor caps, use less of the ignition’s energy to make the spark and thus, have a more powerful spark. If your machine requires the long reach type plugs, use the NGK EV or EVX type spark plug. For short reach, use the NGK HV, HVX or HIX type plugs. Most of the other plug manufacturers also have plugs like this in their product lines. If you must resort to using a resistor type plug, we recommend the NGK IX (short reach) or EIX (long reach) series. These resistor type plugs have the least amount of resistor in them. Do not use the G, GV, or S (standard) series type NGK plugs, as these type plugs require more of the ignition’s current to make the spark and will cause starting difficulties or no starting at all.
For a digital PVL ignition, you must use a resistor in the spark path. We recommend that you use a resistor type cap such as the 5K Ohm spark plug cap supplied with your PVL ignition, rather than using a resistor type spark plug.
Gap Setting: In engines that are very high compression, it is recommended that you use a plug gap of 0.020" – 0.022”. In extreme cases of engines with very high compression and running on alcohol or fuel, it may be necessary to bring the gap down as low as 0.018”.
Section 8: SPARK PLUG CAPS: Included in this kit are non-resistor cap/caps for analog systems, resistor type caps for a digital systems The spark plug caps that are supplied with this PVL Ignition kit, although very economical in appearance, work very well. Digital version PVL ignitions require a resistor spark plug cap of 5K Ohm value, as is supplied with kit, to work correctly. A resistor cap is normally imprinted with the value (5K/5000 , etc.) and the symbol for Ohms (the Greek letter Omega, sort of an O with the bottom cut out and wings on each side of the cut).
The best method of installation is to strip back about 32mm of the wire and bend this portion of the wire over at 90 degrees to the insulated portion of the wire. Then, at a point about 1?4” back from the end of the insulated portion of the wire, press the pointed tang of the terminal spring through the insulation so that it contacts the wire on its way through the insulation. Use a pair of pliers to press the tang all the way down tight. Once the terminal is in place with the spring loop at the end of the wire, wrap the stripped portion of the wire around the end of the spring loop to insure contact. Spray a little contact cleaner on the insulation boot and quickly slide into place over the spring loop and wire. This assembly works very satisfactorily for off road use.
Section 9: Kill Switches: When using a tether switch on an ATV, you must use a separate tether for each high tension coil. A twin cylinder actually has two ignitions, so it is necessary to use either two separate shut off devices or a device that is capable of handling two separate circuits independent of one another. If you are using a toggle switch, you must use a double pole/single throw switch to keep the circuits separate during operation. The red wire exiting the coil or CDI module is to be used for the kill button wire. Connect the red wire to the “hot” side of the switch/tether and the opposite side of the switch/tether to ground. When the two sides of the device are connected, the charge from the stator is then taken to ground, stopping the engine.
PRECAUTIONS While nearly all electronic ignitions are resistant to moisture during operation, they will suffer damage if moisture is allowed to seep into the windings and from the subsequent corrosion that will occur. We recommend that after use, the magneto cover be removed to allow any accumulated moisture to evaporate. This is especially true after washing the machine with high powered spray equipment. An added benefit of doing this is that you will be able to spot any other problspot any other problems that have arisen due to a failing seal or bearing. A failed bearing will nearly always result in a destroyed ignition.