555 Rally: Bikers Roll Like it's 1974

I seem to hear about all the good things too late. The other afternoon, I ran into my friend Chris who turned me on to the 555 Ride, a beater motorcycle rally from Portland, Oregon to Knoxville, Tennessee. The ride has three rules: bikes must be less than 500cc, worth less than $500, and built before 1975. Damn good idea. Got a beater bike worthy of the challenge?
It’s too late for this year. The ride, which is in its second year, began on June 19 and ends on July 4. That’s a lot of miles in a couple of weeks on a beater bike. Check out some of the beaters that started in Portland this year.
What’s your idea of the ultimate 555 bike?