Hello I'm new to the forum and i bought a '00 400ex yesterday and put about 2 hours on it today. While riding i noticed a ticking that definately sounds like valves. I'm under the impression valve noise is common on 400ex's. My bike doesnt have any signs of needing a valve adjustment. It starts right up and has good power. My buddy with a 660 was only beating me by about a quad length or less and the drag was long enough for me to top out 4th.