Yesterday while riding had put in about 200 miles. I went to accelerate and my bike started sputtering on acceleration. If you run at a constant speed it runs smooth. And after a few miles it will clear up and accelerate smooth, but then a few more miles it will start sputtering on acceleration. Today i put new plugs in it and cleaned the air jet holes out. I ruled out fuel cause my wife fueled the same place as i did and hers is running fine. Any ideas on what i need to look for. Also it is showing no codes. Also lost my fuel mileage about 135 on a full tank of gas. It is showing no codes. The plugs are getting black really quik.