This one can be a pretty serious issue. It is caused by two things. The first is not checking your oil by the book, the other is caused by the crankcase vent tube getting pinched under the seat. Not something you want happening when you are 50 miles from the truck.

Like I said, cause number one here is not checking your oil properly. The bike cannot be checked cold because it is a dry sump engine design. Run the bike for 5 minutes or so, then check the oil. If you check it cold, you are going to be a guaranteed .5qt over full. That's a lot in a system with a capacity under 2qts! Oil dripping from your airbox is a symptom here also.

Cause number two, the vent, is as easy a fix as simply removing your seat and making sure the vent is not getting pinched anywhere.

Honda has upgraded the seals somewhere in the '01- '02 production years. The new seal has a thicker sealing lip. The new PN is 91205-MBN-672. It's around 5 bucks and a simple fix. Remove the sprocket, c-clip, and old seal with a dental pick. be careful not to damage any of the surrounding surfaces. It's cheap insurance, and you won't even lose any oil.