So I went to adjust the valves on my 04 yz 450 today and I found that the two intake valves furthest from the cam sprocket were so tight that I couldn't get my smallest feeler guage in. I took the intake cam off and find scarring on the cam journals. The metal has mushroomed over the buckets so I can't remove them. The bike doesn't have a lot of hours on it and has always had regular maintenence oil changes etc. The fluids are always topped off. What might cause this? Who can fix the head? I've heard that overtorqueing the cam caps can cause this problem. Any experiences or advice?