10. New Aerostitch suit too stiff to raise arm.
9. Removing a hand from the bars is considered “bad form”.
8. Your bike isn’t weird enough looking to justify acknowledgement.
7. Too sore from an 800-mile day ride on a stock “comfort” seat.
6. Too busy programming the GPS, monitoring radar, listening to Ipod, XM, or talking on the cell phone.
5. He’s an Iron Butt rider and you’re not!
4. Wires from Gerbings are too short.
3. You’re not riding the “right kind” of BMW.
2. You haven’t been properly introduced.
1. Afraid it will be misinterpreted as a friendly gesture.