good point......
Not atall easy...
I'm not even sure you can.......as the timing marks on the rotor which you view through the little sighting hole (presumably where the oil comes from) won't be visible at the time the strobe strikes.....and will move further away as the engine speed increases due to the timing advance applied by the CDi unit.
you can't change the timing, as the advance/retard is applied by the CDi unit, you can only ensure the static timing is correct, this is set when the engine is reassembled, and the timing marks on the cam wheel and piston TDC are used to achieve this.
if you really want to see the CDi unit 'working' you'd need a dual beam oscilloscope, one beam attached to the signal from the pickup supplying the trigger for the CDi, the other beam attached to the HT lead (couple of turns of wire round the ht lead the attached to the scope lead) the scope would use the CDi trigger as its trigger too, then as the engine speed increased you'd see the HT pulse move in relation to the trigger pulse.....what you then see is what is known as 'the advance curve'.....but this of course is academic, as the timing can't be changed....unless.....you throw away the CDi unit and buy a programmable one (i have one on my SRX track bike) where you can then set your own advance curve, and accept various other inputs (throttle position, wheel speed front and rear etc) to further fine tune engine management.
hope this helps
