I measured my valve clearance at 600 miles and it was close enough to spec to leave it. Intake were dead on at .007, .007 inches. Exhaust was at the tight limit of the spec at .010, .009. I checked them again at 3,800 miles and found that all four valves needed adjustment. The intakes had tightened up to .005 and .006 inches and the exhausts were .007 and .008. Time for some shims. Measuring the valve clearance is easy. Anyone can do it at home. Three bolts and the side fairings pop right off. One bolt and the radiator can hang down enough to sneak the valve cover out the front. Remove the spark plug so you can bump the engine into the correct timing positions for each cam with the lobes straight up, away from the roller. Measure with feeler gauges. Easy. Changing the shims is much more risky and will be better left to a bike shop unless you have a full selection of professional tools and are very good with them. The amount of time it will take you might be better used to pay the bike mechanic who does this sort of thing all day long and has all of the parts handy with out driving back and forth. You can always measure again when you get home to check his work. If you do try it yourself, it might be worth it to pull the tank and move the wiring and splash shields so you can reach right down from the top. I snuck mine in with the tank in place but ended up using a bore scope to see what I was doing for the exhaust shims and probably wasted more time trying to be careful. At least I didn't drop them down the engine which would be pretty easy to do. I changed each shim to the next thinner one and ended up with the intakes at .009, and .008 inches and the exhausts at .009 and .011 after bumping the engine around ten times to make sure everything was seated. The left exhaust didn't change as much as I had calculated it would. Don't know why. Maybe there was a piece of dirt under it and it will run in. I wanted to take them all to the loose end of the tolerance so I wouldn't have to do it again for quite a while but now I will have to recheck them again in a few thousand miles.