Yah, no pics, and I don't think Charlie and Max are the same person.
I'm reasonably sure the 250 class did not go from 135 to 153 mpg by getting rid of aerodynamics
"Craig Vetter started his famous motorcycle high mileage contests which Charly saw as a great aerodynamic research project, getting 135 mpg (2nd place) in 1981, on his XL250."
BMW Motorcycle Windshields, Fairings