I have just performed the first replacement of the air filter element on my '08 Bandit. I was amazed at how dirty the sucker was after only 18,000 kms (11,185 miles). I held the old and new up to the light and no light whatsoever was getting through the old one.
The shop service manual calls for me to un-cork the drain tube that hangs down under the right side of the bike to drain the airbox. However, nothing came out.
What fluids are supposed to drain (water, fuel?) and how could they get by the filter on the clean side of the airbox? Perhaps in warm, humid climates there might be some condensation (not usually the situation here on the west coast of BC)
Oh, and don't be intimidated by the tank removal requirement. It was pretty straight forward; it came off and went back on without any trouble at all.