Ignition Coil Wiring

[azruss]

this will drive you nuts because i'm going to send you off in a different direction. what is the condition of your heads. when was the last time you had valve guides and seals replaced. what temp range are your plugs. are you running multi point plugs. would have like to have heard the exhaust some more and how that changed with each successive rev up and down. theory here is you may be sucking oil thru your old seals and guides and fouling your plugs ever so slightly. sounds like your ignition is strong enough to power thru most of the time. a multi tip plug helps this situation. A different heat range plug could help keep them clean. also might ask about resistor plugs. when my old tired 2L carb started fouling plugs, i could just pull the plug wire off the plug and let the spark jump the gap for 30 seconds and the miss would clear up.