- Nov 16, 2003
I'm a new rider with a 2003 kdx220. I was wondering how often you guys foul spark plugs. I seem to foul at least one every 40mi, and they are covered with black buildup. Is this normal, or is there a problem with my bike. Also, I am sure the fuel mix is right (that's what i guessed the problem was at first, but the bike continues to foul plugs very often).