05 450r not running good

[QuadRacer041]

im posting this for a freind of mine. he just bought a used 05 450 that is all stock. we went riding yesterday and after about 30 minutes it just started running like crap. it will idle just fine but as soon as you give it gas it dies out. starts right back up and idles fine fine....but as soon as you try to hold the throttle open it sounds like it is choking out. spark plug looks good, air filter looks fine. it sounds like a fuel problem but why doesn it idle fine???? after this happened he told me that the previous owner told him he had that problem before, he brought it to the dealer and $300+ later they told him they had to adjust his valves, but that doesnt seem like the problem to me.

any ideas?

[lil_billy_300ex]

sounds like your main jet is dirty.

[genxracer]

maybe the main jet fell out. Or maybe The clip came out of the needle. Gotta be the carb or some type of intake problem....clogged air filter or passage.:confused:

[MAD450r]

try this put it on reserve and see if its better. If it is time to tear the fuel petcock apart and clean it. If thats not it then its time to clean the carb. I was lucky and it was bad gas that cloged my fuel petcock some and it flow's fine on reserve.