I really had no idea. Why has this taken so long? I remember Nelson Vails way back in the 1984 Olympics was something of a pioneer.
http://online.wsj.com/article/SB10001424053111903554904576462463771685924.html?mod=sports_newsreel
Though there are no definitive records to prove this, Tour organizers say Yohann Gène, a 31-year-old professional cyclist from Guadeloupe, is—so far as anyone can remember—the first black rider to compete in the 108-year-old race.
http://online.wsj.com/article/SB10001424053111903554904576462463771685924.html?mod=sports_newsreel