Beijing road race Olympic champion Nicole Cooke has attacked drug cheats in her sport after announcing her retirement from professional cycling.
Cooke, 29, said she had come under pressure to take performance-enhancing drugs during her career.
The Welsh cyclist also claimed she had been "robbed" by cheats.
But she added: "I am very happy with my career. I have many happy memories over what's been a life's work."
Announcing her retirement on Monday she said: "I am now 29 so that's 17 years of my life I have enjoyed and now I am bringing to a close. I won every race and more than I dreamt I could win.
"You cannot believe how happy I am being able to stand here with my dreams fulfilled."
But she went on to attack the cheats who she said had brought about the "darkest days" of the sport.
She said: "Every scandal on the men's side has caused sponsors to leave on the women's side. With such thin budgets, the losses have a greater relative impact on what survives.
"I have had days where temptation to start onto the slippery slope was brought in front of me. In my [first] Tour de France, when I was 19, as the race went on my strength left me.
"I was invited into a team camper and asked what 'medicines' I would like to take to help me and was reminded that the team had certain expectations of me during the race and I was not living up to them.
"I said I would do my best until I had to drop out of the race, but I was not taking anything."
She then spoke of her fears for the sport unless the cheats could be driven out.
She added: "I do despair that the sport will never clean itself up when rewards of stealing are greater than riding clean. If that remains the case, the temptation for those with no morals will always be too great.
"I have been robbed by drugs cheats, but am fortunate. I am here with more in my basket than the 12-year-old dreamed of.
"But for many people out there who do ride clean - people with morals - many of these people have had to leave the sport with nothing after a lifetime of hard work, some going through horrific financial turmoil."
She also said there should be no sympathy for disgraced Lance Armstrong when he gives an exclusive interview to American chat show host Oprah Winfrey this week.
Cooke said: "When Lance cries on Oprah later this week and she passes him the tissue, spare a thought for all those genuine people who walked away with no rewards - just shattered dreams. Each one of them is worth a thousand Lances.
"I have ridden through the time of Lance and all of the dreadful tragedy that the abuses surrounding him have brought to my sport.
"I have faced up to the temptations but have always remained true to the 12-year-old inside me.
"Yes I have suffered as a result, in many ways, but so what? I am not alone, I am one representative of that group, those who do it right.
"I have ridden through some of the darkest days of the sport in terms of corruption by the cheats and liars.
"I cannot change the era or time that I am born into. I am very proud that I have ridden true to myself and placed my morals beyond a need to win. I have ridden clean throughout my career in a sport so tainted.
"I look forward to the exciting next chapter of my life and thank everyone for supporting me during the last one."
Cooke has always felt British Cycling could have done more to help her career and was dismayed as a 17-year-old in 2000 when the sport's national governing body decided not to fund an appeal to overturn the minimum age for the Olympic road race.
In 2009 she launched her own team, Vision1 Racing, "to keep things interesting" and further her own career.
However, the team folded the following year and Cooke joined Italy-based Mcipollini-Giordana.
Ahead of London 2012 she was involved in a battle with fellow Briton Lizzie Armitstead for the number one status.
Cooke had to settle for a supporting role as her rival claimed Olympic silver.
She returned to action for September's road race World Championships but finished 60th, more than five minutes behind winner Marianne Vos.
The rivalry between Cooke and Armitstead has been well documented and veered towards the unpleasant at the 2011 World Championships in Copenhagen.
They were named in the same GB women's team, with Armitstead the leader. She looked well-placed to contend for the title until a crash late in the race separated the pair.
Armitstead felt Cooke, who went on to finish fourth, abandoned her in the subsequent melee, but the Welsh cyclist felt she was in a better position to win the race.
Following Cooke's retirement announcement, Armitstead tweeted: "Congratulations to Nicole Cooke on a fantastic career!"
British Cycling president Brian Cookson said: "One of British Cycling's finest moments in recent years was her truly memorable win in the women's Olympic road race in Beijing.
"There is no doubt that Nicole has been a pioneering force in women's cycling for the past decade.
"She inspired many youngsters to take up our sport. British Cycling owes a huge debt of gratitude to her and wish her all the best."