At age 19 , John was the youngest cyclist on track in the 1968 Mexico City Olympics , he rode and earned a bronze medal at the 1971 Pan American Games .
At 23 cyclist was the oldest John at the 1972 Munich games .
At age 19 , John was the youngest cyclist on track in the 1968 Mexico City Olympics , he rode and earned a bronze medal at the 1971 Pan American Games , and at 23 he was the oldest cyclist at the 1972 Munich games .