CONNECTION: The CDI has four wires, two which connect to the blue and black wires from the magneto coil, and two which connect to the motorcycle ignition coil. The wires to the magneto coil need to be soldered to their mating wire and then the heat shrink tubing shrunk over the exposed metal for good insulation. (Put the black heat shrink tubing on each wire before connecting wires. Solder the wires and then place the tubing over the exposed connection, then shrink it with heat from the soldering iron or a small flame.) The Performance CDI can be reverse wired from CDI to high voltage coil for stronger spark and longer plug life. (read more) (in the drawings below it is reverse wired in the first one, and wired standard in the second one). With it you need to make sure the metal frame of the high voltage coil (if it is exposed) does not touch the bicycle frame or any metal of the motor in order to prevent the CDI output shorting to ground. Also it's best to coat it with silicone sealant to prevent people from getting lightly shocked with the pulses of voltage from the CDI if they touch it and the engine at the same time. You can connect it to your bicycle frame just using the double sided foam tape already stuck to its underside and some black electrical tape. The ignition coil should be held in place with a hose clamp. To connect the CDI ground wire to the ignition coil frame you'll need a 1/4" diameter bolt (at least 5/8" long), nut, and washer. This shows the connections:

CDI wiring

CDI wiring
If you have the older CDI model then you can use a soldering iron and switch the two output wires of the CDI, either at the connectors or within the CDI box. (click here for the nitty gritty technical details)
Questions & Answers

Does my spark plug need the screw-on nipple that was taken off to work with the spark cap supplied with the Grubee engine? Yes, you will need that to match the new motorcycle spark cap. If you don't have one then splurge and buy an iridium or platinum tipped spark plug to give you the best performance.

How can I test it to see that it produces a hotter spark? Just take out the spark plug, connect it to the spark plug cap, hold the spark plug onto the cylinder head so that it is grounded, and with dim lighting (best at night) push the motorbike and you will see the actual spark. Do this same routine with the standard ignition system before changing to this new system so you will have a point of comparison. Here is a video showing the Performance CDI and Kawasaki motocross coil sparking a gap 5 times normal. Normal is .025" and the gap with the ground electrode bent out is .12" on this plug. The voltage source is the normal Grubee magneto rotated by an electric motor to power a Grubee stator coil.

Does it come waterproof? It is sealed where the wires exit the box but it will be more waterproof if you position the box onto the frame so that the box lid is the low side. That way no water can rise and contact the electronics within. I've ridden occasionally in the rain for 2 months with even less waterproofing and have had no problems.

What if I need to extend the CDI wires to be longer than they are? Just go to Radio Shack and buy these to extend your wires: Hookup Wire (22AWG) # 278-1224  $7.40, Heat-shrink Tubing Set (36-Pack) # 278-1611  $4.20

What if it stops working and I want to troubleshoot and repair it myself? Go to this page for full instructions on troubleshooting ignition problems.

Selection of Timing Curve
If you take off the box lid (using a small phillips screwdriver) you will see the rectangular switches on the components board. They allow selection of timing cur
ve to match your setup.  For full information click here.
switches on CDI board