But the water splash will wreck havoc with the under-tank relays, wire terminals, coil, just about anything that should not spend time playing in the kiddie pool. The engine front cover also has openings on the bottom, so plan on future issues with the diode board, alternator and perhaps the ITU.
You really don't see to many uber custom cafe Airheads on the road. They are usually one of two things: 1) Trailer Queens, or 2) Not running. Quoting an Airlist friend, Just my opinion based on my limited experiences.
Your bike and your coin, so please do with it as you wish and not what others might tell you to do. Besides, Cali hasn't seen much rain in a few years and is already tinderbox dry. Water on the roads? Meh.