Tour de France winner Bradley Wiggins believes Lance Armstrong may never confess to doping because he is "stubborn" and has "too much to lose".
Wiggins said Armstrong should come clean to prevent further damage to cycling's tarnished image.
Armstrong has been stripped of seven Tour de France titles and banned for life for doping offences.
Wiggins said: "You realise as you grow up that Father Christmas doesn't exist. That was always the case with Lance."
A United States Anti-Doping Agency (Usada) report called the American a "serial" cheat who led "the most sophisticated, professionalised and successful doping programme that sport has ever seen".
Armstrong has kept quiet since Usada's report was published earlier this month.
Asked whether Armstrong should confess, Wiggins told BBC Sport: "I think so yeah, yeah, definitely.
"But everyone knows he's a stubborn man. He has too much to lose, but the evidence speaks for itself. [It] looks overwhelming.
"There's a lot of anger. It's a shame cycling has being dragged through this again. It had to come out.
"Us riders here now - and I think I speak for all of us - we're the ones picking the pieces up and having to convince people the sport has changed.
"It's difficult to convince people because of the precedent that's been set and I haven't got the answer, other than to do what I'm doing."
Wiggins's fellow Briton Mark Cavendish described revelations about Armstrong as "frustrating", but insisted cycling is one of the cleanest sports.
"If you've done something, confess," he said. "That anyone can damage the sport I love right now, it's frustrating."
Despite evidence of widespread systematic doping in the past, Cavendish maintains that cycling only appears to have more dopers because the testing is much more stringent than in other sports and insisted there are cheats in "every walk of life".
He told BBC Sport's Matt Slater: "There are cheats in entertainment, journalists cheat, every single sport has cheats.
"If you put the effort into catching them and you have a structure that does things properly, you're going to catch a cheat.
"It doesn't happen in other sports, not because they are clean, but because it's not got the structure cycling has. In my eyes, cycling is the cleanest sport."
Cavendish said he respected those such as Great Britain team-mate David Millar who have openly discussed their doping and therefore played a part in trying to clean up the sport.
"I've worked with David Millar," Cavendish said. "This guy's remorseful. He's repented."
He also praised others, including his former HTC-Highroad team manager Rolf Aldag, who admitted to doping during his time as a rider.
"These guys care about the sport," he said. "They ruin their reputation to move the sport on, but other people care more about themselves."
In his candid interview with BBC Sport, Cavendish also said he felt let down by Team Sky, arguing he was misled by the British-based team into believing they would compete for the green jersey - awarded to the rider with the most points, usually won by sprinters - in tours.
The Manx sprinter, 27, said he joined Team Sky in 2011 believing he would be able to battle it out for the green jersey in the Tour de France points competition, but ended up taking a back seat as team-mate Wiggins secured overall victory and the yellow jersey.
"I wouldn't have gone to Sky in the first place if they had said you're not going to win the green next year," Cavendish said.
"If I wanted to go just for green, I wouldn't have gone to Sky anyway, but we had this idea of yellow and green and that it was two British riders on a British team backed by British sponsors.
"That was a big thing for me. I'm a patriotic lad."
Cavendish said Sky's decision not to go for green "kind of threw what my whole career is about into turmoil", but said he would not rule out a return to the Dave Brailsford-led team in the future.
"The best thing I did was go [leave Sky]," added the 2011 world road race champion, who will ride for Omega Pharma-QuickStep in 2013.
"I wanted to stay friends. I wouldn't rule out ever going back, but that's up to them. I had a wicked time and was part of history."