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07 yz450 mis-fire need help!!

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rode my bike last weekend ran great parked it in good running order,went to ride yesterday,so the bike sat un-touched for a week,started fine as soon as the choke was shut off it died,started it back up ran like crap would barley run with the choke off,was backfiring and popping the entire time.any ideas?the only thing that i am questioning is that it was really hot yesterday and the bike had sweat all over it,i would think that it would be fairly water proof but i know that sweat can develope in odd places

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Sounds like a clogged pilot jet to me. Buy a new one and replace it for about 8$.

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Sounds like a clogged pilot jet to me. Buy a new one and replace it for about 8$.

thanks for the help thats what i thought as well,so after spending 2 hrs tearing it down inspecting,cleaning and reinstalling the carb,and a new spark plug it did the exact same thing...turned out to be bad gas:banghead:i was beyond pissed off,so i lost a day of riding and 2 hrs of my life from a bad batch of fuel,not to mention the $7 per gallon 110 that was mixed with it:foul:

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