I am starting my vetter challenger project for the challenge in Ohio in July, and will be documenting the build here. I went to last year's challenge with my stock '81 Yamaha sr185, but the 600 mi ride down in 100+degree heat caused some problems with tire wear and overheating. I blew my rear tire halfway through the challenge, and had to get trailered back to the starting point. Anyway, here is what I have planned so far.
The Bike: '81 sr185- because I already have it
Full fairing with tail, I am going for 24" overall width, and 8' overall length. it will likely be somewhat boxy looking, as I am trying to go for as few compound curves as possible. i read somewhere (can't remember where) that even a brick with rounded edges has better aero than a motorcycle
this plus taller gearing should put me in the 100mpg range, since it can get 100mpg at lower speed (50ish mph).
the biggest obstacle will probably be cooling the engine since it's an air cooled bike, I plan to find a 12" radiator fan and place it in front of the engine with ducting to make the airflow pass over the cooling fins and vent out the back of the fairing, I also wrapped the exhaust header with fiberglass insulating tape made for sport/race cars which should move more of the exhaust heat away from the engine.
Wish me luck,
P.S. Hopefully I'll be taking some pics today to post later