Beamon's record of 8.90 metres, set at the 1968 Mexico City Olympics, lasted 23 years. It is possibly the greatest Olympic track and field record; it is indisputably the most spectacular.
2004 Athens Olympics: Complete Coverage
"I can't believe it's 40 years," Beamon told the teleconference. "It was an incredible day. It was one of the few times in my life that I felt I was going to be a champion.
"I had an incredible spirit of life, if it snowed, if it rained, whatever, I was basically prepared to jump in any kind of weather."
Beamon graduated from a troubled childhood in New York City into the turbulent 1960s as an athlete of rare gifts.
In the thin air of Mexico City he trained over 100 metres with Tommie Smith and John Carlos, who were to stun the world when they bowed their heads and raised their right fists in the black power salute after finishing first and third in the 200 metres final.
"I came to Mexico probably running 10.4 (seconds) and I worked with the great Tommie Smith and John Carlos and I could probably have run 10.00, 10.05, 10.06," he said.
"That was a key issue for me. What I did was learn the technique with being with the great ones."