i just had the same problem as u explained, i had my iridium plug in when it started to crap out, i took it back out and put an old one in and it would then crank up but would run rough, sputter and smoke alot, couldnt go below half throttle or it would die out, i have my bike jetted as well but didnt mess with the fuel/air mixture screw at all, now the bike wont even start, so there is a fuel problem somewheres, i dropped it off at a guys house on sunday and he is gonna look at it and get it running again, he said he hates bikes with snorkels cuz they never run right after that, and then he hates bikes that are jetted cuz i guess it is more work to be done on them or something, i just said get it running and if he jetted down ill tear it back apart and rejet it myself....not sure what it is though maybe its some mysterious bike hater plague running through LA