Selectable Timing Curves

There are two on-board switches on the circuit board.

Switch 1 (SW1) is a dual switch that controls the whole ignition timing curve (to be more advanced or retarded/delayed) but affects mostly the middle of the curve. 


Switch 2 (SW2) is a triple switch that controls the amount of retard curve to the timing after 3000 RPM without changing the low RPM timing. So it has the most affect at high RPM.

DETERMINING BEST SETTINGS: You can test the settings for your bike to see what works best. Jetting, porting, compression*, and exhaust pipe all affect the needed timing. Which ever settings allows the best power are the ones you should use.

* high compression heads with squish bands (when the clearance to the piston is no more than .8mm) burn the mixture quicker and so needs retarded ignition

Leave the switches as they are. Go for a ride and note your top speed. (first please buy a WalMart speedometer if you don't have one!) Then move one of the switch 2 levers to the off position and ride again. If slower then move two switch 2 levers to the on position and test ride again, or if faster then move another switch 2 lever to the off position. Keep testing till you find the best settings for the fastest speed. If you reach your fastest speed with all switch 2 levers in the off position then move switch 1 for the next higher resistance. If faster then keep repeating till you find the fastest speed. If you reach your fastest speed with all switch 2 levers in the on position then move switch 1 for the next lower resistance. If faster then keep repeating till you find the fastest speed.

If you have an expansion chamber: Take it off and do the test procedure above with the stock pipe. Then put the expansion chamber on and retest speed. If slower then your header (straight pipe from engine to chamber) is too long. That header length determines the speed at which the expansion chamber limits speed. It has to be "tuned" for your ride. The shorter it is, the more the top speed. (but keep in mind that the stock low height of the exhaust port also limits top speed and it has to be raised at least 2mm for a significant improvement in speed. Raise the transfer ports 1mm for every 3mm change in exhaust port.)
 

HOW TO UTILIZE THE SWITCHES: Just remove the boxes 4 screws (hidden under rubber feet) with a small Phillips screwdriver. Once the box lid is removed you can see the switches and easily change their lever positions using your fingernail or a small screwdriver. Switch 1 on positions are "up" and switch 2 on positions are "left" when the components board is positioned the same as in the drawing below.

More resistance (in ohms selected by switch 1) causes more ignition advance. More capacitance (in uf selected by switch 2) causes more top RPM ignition retard.