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I read this somewhere - words to the effect - "Ducatis are wasted spark ignition - firing every crank turn and the marginal coils (on carbies) do not get enough time to recover before being fired again. If you add in a bigger plug gap the coil barely pushes out enough juice to jump the gap and when it does the spark is a bit later so the actual burn of the fuel commences later i.e. the actual ignition runs a bit retarded (the timing trigger says go but the conditions in the cylinder head determine when the spark actually jumps, low revs wide open throttle being the worst condition i.e high cylinder pressure and early in the advance curve so the spark fails and the engine fluffs).
The stick coils on wet bikes have an even lower output than carbie ones c20k volts but the ECU compensates for the lower spark ouput by reading ambient vs engine temperature, revs and throttle position and immediate throttle demand history ( I may be wrong on this last point) and almost instantaneously amends the timing to get the optimum burn rate in the cylinder".
Obviously a better solution if all the sensors, connectors and associated wiring and the ECU are in good condition but a right PITA if any are less than perfect or worse intermittently good.
Except for the last sentence, I think this was written by the NZ bloke who runs Fastbikegear and it was my justification for buying his expensive Hall effect ignition triggers that work off the central cam belt pulleys which obviously operate at half engine speed.
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