2007 yz450 excessive popping and stalling out

[jarhead83]

I purchased 07 yz450 ,the person I bought it from said bike been sitting for about six months.Bike seems to start fine and idles ok, once you start riding every time you let off throttle the engine backfires and pops a lot, then stalls out. If you don't keep the rpm's up when slowing down bike will stall out. I removed the carb and cleaned ,added fresh gas, and replaced the spark plug to see if that would fix the concern. I started riding and again still have the same concern,HELP.   

[mikedabike]

Replace the pilot jet and adjust the fuel screw per the manual. Once they varnish up they are hard to clean since the opening is so small.

[grayracer513]

There's no real problem cleaning a pilot jet.

 

https://www.thumpertalk.com/forum/showthread.php?p=8021726#post8021726