I started having problems with my 07 KFX700 today. Other than the Uni air filter, it is completely stock. It does not smoke, the air filter is clean and not over oiled, and spark plugs are fairly recent. As stated, it had been running perfectly fine before today. Anyway, it starts up easily and idles fine. The problem is that it cuts out and sputters when getting on the throttle and runs sluggish. It does get up to speed, but it doesn't do so smoothly. The valves are within specifications and I have disassemble the carbs and they were spotless. I still cleaned everything out with carb cleaner and compressed air, and replaced the jet with oem parts (stock sizes). I have also drained the tank thinking that there might be water in it. It was also very clean...no debris or water. Thanks in advance for any help in trouble shooting.