So, I was looking around and saw a number of threads that had suggestions as to how to change spark plugs, but it still seemed as though there were a number of questions that kept coming up. I decided to take pictures while I changed the plugs on my '08 to hopefully help guide others who want to attempt this task. IMHO, the airbox route is the cleanest way to do it (as opposed to the radiator route, which really is only good when you are changing your coolant anyhow), and it really isn't that hard. If anyone has any suggestions, or if I missed anything, please feel free to flame the piss out of me!
Tools: For this job, I used the following:
4mm Allen key
5mm Allen key
#2 Phillips-head screwdriver
3-inch socket extension bar
10-inch socket extension bar
3/8-inch universal joint
5/8-inch spark plug socket
long-nose vice-grip pliers
Spark plug gap gauge
All-in-all, this was about a 4 beer job.
Step 1: Remove the seat (hopefully no picture is needed for this step)
Step 2: Remove the plastic, tank-side panels (one Phillips screw per, then slide forward).
Step 3: Remove the three Allen-head screws securing the tank (2 on the sides, one on the front) with the 5mm Allen key.
Step 4: Lift the tank and disconnect the breather tubes from the bottom of the tank.
Step 5: Disconnect the two wiring plugs and fuel line from the bottom of the tank (have a towel handy, there will be a little fuel in the line).
Step 6: Remove the pivot bolt at the back of the tank with the 5mm Allen key, and remove the tank.
Step 7: Remove the 11 Phillips-head screws from the perimeter of the airbox and lift the top half off and to the rear (rest it where your tank would be).
Step 8: Loosen the 6 Allen-head screws from around the velocity stacks using the 4mm Allen key, and the 2 Phillips-head screws holding the YCCI unit on.
Step 9: As you lift the bottom of the airbox out, disconnect the breather tube using the vice-grips (the bottom of the box seals pretty well to the throttle-bodies, so gently wiggle it loose). Place the bottom of the box with the top portion. Also remove the push-clip from the center of the intake shroud.
Step 10: Remove the plastic intake shroud to reveal the intake solenoid.
Step 11: Using the vice-grips, remove the two clips holding the tubes on and work that little sum-bitch outta there.
Step 12: Pull back on the heat-shielding to reveal the spark plug boots. Disconnect the wire harness and, while twisting on them, pull the boots off of the plugs.
Step 13: Using the ratchet, extension bars, u-joint and spark plug socket, remove the spark plugs. Inspect the plugs for wear, adjust gap and reinstall. If you are replacing them, adjust the gap on the new plugs and install. When reinstalling the plugs, torque down to 9 ft-lbf per the manual using the torque wrench. Once the plugs are in, work through the above steps backwards to put your bike back together.
I hope this helps and good luck!