Come on guys this has been here for two days and no answers, I'm far from the best at this but I'l give it a shot, first you will need a good shop manual with wireing diagrams, then you say it does have a intermintant spark every now and then, how exactly are you checking that? it don't seem likely that all four coil sticks could be bad, so lets ck, the harness connections to the coils on one wire you should have a constant voltage with the key on, don't know exactly what it should be, ck manual, then the other wire is a intermitant ground that fires the coil when ECU tells it to, so hook to the ground of one of one coil plug, you should really ck them all, then crank over the engine while checking for ground it should spike a signal each time that coil is supposed to fire. I would think that you don't have one or the other, power or signaled ground at the coils, then you need to ck the easy stuff like the kickstand switch, and tip over switch, clutch switch, and ign cut switch on the handlebar, but most of them will keep the bike from cranking over as they also interrupt the starter circuit, then you have the cam sensor, not exactly sure how to ck if bad or if this will prevent spark from happening or just make it go nuts the map sensor will make it run like shit, but should not prevent spark, I guess next you may want to using the manual trace the ECU grounds to be sure none are broken, unfortunately most of don't have spare parts to try, just ck out one thing at a time, it could also have a bad ECU, but dont know till all the other stuff that feeds it is checked first, this is a tough deal, diagnosing this online, I'm sure I forgot something, but maybe some of the more experienced members will post up, fortunately as electronic systems go, the Busa's is pretty simple......good luck and let us know....
