In the first modern Olmpics in Athens in 1896 there were only 2 competitors in the 100 km cycling race. They were Leon Flameng from France and Georgio Kolettis from Greece. They had to race 300 laps around the track.
While Leon was in front, Georgio's bike broke down. Instead of continuing to ride the race and win it Leon stopped and waited until Georgio had fixed his bike. After the bike was fixed the race continued.
This was an example of fair play by a true Olympian.