Tour de France, Giro, Vuelta, and classic European races show a unique progression of road cycling speed in the last 20 years. A French group has studied the development of the performance of cycling icons and large cycling tours in the last 116 years. It showed various development periods over time, with a fourth period after 1993, a performance improvement of 6.38% compared to the third period. The possible reasons for this performance jump are discussed under https://pubmed.ncbi.nlm.nih.gov/20473822/