I bought a 2004 ninja 250r. Had only 1360 miles. I rode less than 100 miles and was stranded on the highway. Thinking maybe carbs gummed up I cleaned the carbs and decided to change the plugs also. To my horror the left plug electrode and insulator was completely burned away. Left cylinder has zero compression now. Searched the web to find that Champion plugs are notorious for destroying ninja engines. For some unknown reason the previous owner put in champion plugs and now I am stuck with at bike that only has 1400 miles, no compression and a hole burned thru the left cylinder. UGGH!!!!!!!!!!!!!!!!!!!!!!!!!!!