So I take my 01 WR 426 in for a valve adjustment. The bike has over 250 hours and 4700 miles on it. I had the valves checked once after having a Hotcamshafts auto deco intake cam installed at around 2500 miles. After the cam was installed no valve adjustment was required. This latest time the valves checked out dead on again no adjustment required. I was amazed. I asked the mechanic again and again and he swore they were dead on. This engine has proved to be iron tough and reliable as hell. Very happy with it.