It would be another 20 years before a New Zealand cyclist would finally officially claim an Olympic medal, when Gary Anderson won bronze in the individual pursuit at the 1992 Barcelona Games.
The International Olympic Committee ignored Biddle's claims. In Our Olympic Century, sports historian Joseph Romanos tells of the last effort to honour Biddle in 2002 when IOC president Jacques Rogge visited New Zealand.
The late John Davies, 1964 1500m bronze medallist and then New Zealand Olympic Committee president, presented Rogge with a dossier. It included affidavits from the 1972 New Zealand cycling team manager and chef de mission.
Months later, the IOC advised nothing could be done because the race was organised by the International Cycling Union, who refused to budge. So much for IOC clout.
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Significantly, AT Biddle's first road race after the Olympics, organisers in Tuscany presented him with a gold medal.
Biddle appreciated that. He still lives in Tuscany, in the port city of Livorno. Born in Warkworth, he has resided in Italy since Munich, marrying Daniela.
They have a 30-year-old son working as an engineer in Rome and a 22-year-old daughter training to be a school teacher in Florence.
Now 62, Biddle told the Herald on Sunday when he's not enjoying the Italian food, wine, people and culture, he often pedals 50-60km on a Sunday morning in the Tuscan countryside.
"What's not to like?" Biddle chuckles. "It's nice to have a pedal every now and then. We're out of the way a bit, so there's peace and quiet."
Biddle works in freight forwarding, distributing Italian wines and other beverages around the world. His journey to the Mediterranean started when he and a mate met an Italian shirt button maker in South Africa before the Munich Games.
"I was initially keen on using Belgium as a base but my mind was opened to the various racing options in Italy. I ended up preparing there for the Games [after winning gold in the 1970 Edinburgh Commonwealth Games road race]."
Biddle found the standard of cycling superb and decided he would try to work off the Italian team at the Olympics.
"I wish I'd gone earlier. I learnt how they worked and organised my tactics accordingly. During the race, I realised other teams were also matching their moves, so I took the chance to join a breakaway.
"If I'd come third in the actual race, it would've been the highlight of my career. I couldn't blame anyone other than myself. The irony is the Spaniard [Huelamo] actually did a lot of the work in the front of that breakaway, whereas the Australian [silver medallist] Clyde Sefton ... well, he did less. That annoyed me more at the time.
"I'd love to hear Huelamo's thoughts as to whether he just took some poorly prescribed medicine that might've been legal in Spain. Problems with doping have matured over time. Nothing's been solved, little has changed.
"I think the problem lies with a celebrity culture in cycling. Riders [chasing lucrative endorsements] see it as more important to become famous by winning stages than working as domestiques and helping a team. That drives the decisions to cheat."
Intriguingly, Biddle has a different take on the circus that surrounds Lance Armstrong as he faces further doping allegations. Unprompted, he springs to the seven-time Tour de France champion's defence.
"This latest foray seems unnecessary. Even if he did do it, it was part of the era he was in. People knew about the substances that were being taken.
"Take alleged illegal substance use away, and Armstrong would have won regardless. The press and public are gradually taking away his credibility, which isn't right.
"Don't get me wrong. Cycling's image has a great debt to pay to its supporters for this drug culture. We need to clean up what we can. Look at the grand tours everywhere, even up on the mountains. It's amazing to see the levels of support. We can't solely level blame at Armstrong if everybody was doing it."
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Biddle reflects fondly on a career which took him from pedalling Auckland's Great South Rd under coach Murray Laloli to trekking through the professional tours of Italy, Switzerland and Catalonia. Biddle never raced a Tour de France (only 10 New Zealanders have) because it was never part of his pro team's itinerary, unlike today's more globalised event. Bronze medal or not, he says the 1972 Olympic race was pivotal to his future.
"I was suddenly desirable as a professional. After the Olympics, I came back to Italy, spent one more year as an amateur, then made the switch. I'm content with my results. Various attempts have been made to get me that bronze but the best thing was it gave me a career."
As a pioneering pro, he follows New Zealand riders.
"I enjoy following the progress of Kiwi pros around the world. There are some excellent results and a lot of talent coming through, considering where we came from. For instance, [seven-time Tour de France entrant] Julian Dean has been a mighty ambassador. I'd love to meet him."