Two places from which I draw nearly endless design inspiration are the Ford GT 40 (FMI see "Go Like Hell" by A.J. Baime) and the Porsche 917 (FMI see "Porsche 917, the Winning Formula" by Peter Morgan).
"Rollie" Free setting a speed record at Bonneville in 1948 on a Vincent Black Lightning. One of the most iconic photos in motorcycling history. They just don't make them like that (man or machine) any more.