 During the Czech communist era he was a two time amateur World Champion, but was unable to become a professional cyclist.The earnings he garnered from international matches in Belgium and the Netherlands were paid to the Czechoslovakia Cycling Union and Šimůnek did not receive his winnings.The political change in Eastern Europe in 1989 and 1990 finally allowed him to become a professional, before he won the World title at the 1991 World Championships in Gieten.