Misfire at full throttle in Kawasaki 2 Stroke Posted August 15, 2012 · Edited August 15, 2012 by SPUTTER Sometimes, if it acts overly rich, it is - but not from jetting. After checking out ignition issues, you may want to swap carbs with someone and see if that fixes it. I had purchased a KDX220 that misfired (acted like rich) on top and would not rev out cleanly (sounds a lot like yours)- it turned out to be a bad carb...sometimes an air passage gets blocked internally - rare but it does happen. (I've read of others with that issue too - a bit of carb metal lodges internally-impossible to find). I had completely torn the carb down, including the jet block, ran wires through everything, compressed air, etc. As soon as I swapped out the carb it ran perfectly. The previous owner had gone to great expense trying to lean out the carb, but nothing worked. The piston and head looked brand new, shiney and clean from too much fuel. Try running it out of gas and see if it revs up higher before it dies as it runs out of fuel.