as with any engine you should always set the valves one cylinder at a time. make sure the cylinder you are adjusting is at top dead center on compression stroke. you will know this by noting that both valves will be in their closed position. you can check the timing marks on the flywheel to make sure it is exactly top dead center. if you remove the inspection plug on the side cover you will see the flywheel. there should be identifying marks on it. you are looking for a "T" there should be an index mark on the case that you will line it up with. long as that is lined up your top dead center. now to make sure you are on compression just make sure both valves are closed. remember that when you go to the next cylinder you must rotate the engine so that the next valves are top dead center on compression. adjust with engine cold. factory clearance should be around .002'-.004'. but refer to your manual to be sure.
