The speaker has found a unique way to cram almost everything he finds interesting (fluid mechanics, cycling, hair and free food) into one conveniently sized SUMS talk. In 1989 Laurent Fignon lost the Tour de France to Greg LeMond, by 8 seconds. Anecdotal evidence suggests it was calculated that if Fignon had a haircut, he would have lowered his aerodynamic drag enough that he would have won. This talk will introduce basic fluid dynamics, and discuss how computational fluid dynamics is used to simulate the aerodynamics of cyclists and bicycles. The talk is aimed at being fairly accessible to a general audience.