The most successful MotoGP rider of all time, Italian Valentino Rossi has always worn number 46 because his father used it during the late 1970s. As a multiple world champion, protocol provides that Rossi is entitled to wear number 1, but he has chosen to stick with his lucky number.
According to Red Bull, Rossi's father Graziano won his first three GP races using the number 46.
Rossi has also stuck with the same number through his entire career in part to pay homage to his hero, Barry Sheene.
According to the official MotoGP website, Rossi has never used a motorbike or a car in a competitive race without using his favorite number.