Along with an oil change, valve adjustment is probably something I should have done sooner, and certainly before I started messing with my carbs.
Having never done a valve adjustment before, I was a bit intimidated, but I faced my fears and delved under that valve cover.
It seems that every Amazon junkie has his or her own favorite method for adjusting valves, but after reading various articles I decided to go with the "Rule of Nines" method which seemed to be the best balance between accuracy and simplicity:
"To adjust any particular valve, take its number, then figure out the other number you will need to add up to nine. Turn the engine so that valve is wide open, then adjust the one with the first number. For example, to adjust number one, turn the engine so that number eight is open all the way, then adjust number one. Moving on to number two, turn the engine so that seven is wide open, then adjust number two, and so on."
Interestingly, all of my intake valves were 0.018" (cold), and the exhaust valves were all 0.019". An early warning sign of valve recession, perhaps? I set everything so that a lubricated 0.020 feeler gauge would pass, but a 0.022 would not.