how to set the valves on 2000 atv450s?

Answer 1

Always give year, "make", engine size, and "model #" when asking questions.
--Bring piston to TDC of the compression stroke. (turn flywheel in direction that motor rotates. Observe intake valve. When it opens, then closes, keep turning till piston moves to top of it's stroke).
--Loosen tappet adjuster lock not.
--Insert correct size feeler gauge between tappet adjuster and valve stem.
--Adjust tappet adjuster to proper clearence, then tighten lock nut.
http://www.dansmc.com/valveclearence.htm
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