banshee engine question ?

[ericdoedoe]

ok so im kimd of new to banshees, twp strokes in general,, i have had a banshee for about 5 months now, when i first got it, it did not start, due to crappy jetting in the carbs, so got that fixed and it ran like a beast, till the clutch burned out, got it fixed, but i let my cusin try it out on a stright away, and he was halling ass down it, but then he said it died, and when we push the kick start lever down it would blow smoke out the pipes and woulnt start, by the way the smoke was white as it is when you normally start it, and also the left spark plug had black stuff surrounding the spark plug on the head,, could the falty spark plug be the reason. that incident happend lastweek and i havent ridden it since, but i did start it to put it in the shed, but it took along time, and it ddnt stay on, any ideas ???