THE expletives flew from Bradley Wiggins' mouth like bullets from a Tommy Gun on Sunday evening in response to suggestions that his success was down to doping.

No doubt his reaction to the news that Cofidis had suspended rider Remy di Gregorio on Tuesday would have led to more euros being crammed into the already jam-packed Team Sky swear box. The timing couldn’t have been worse.

The passion with which Wiggins – fresh from a gruelling 98-mile mountain stage – defended himself was admirable. After all, there is no evidence for such slurs.

It displayed the heart and single-mindedness that has put him in great shape to become Britain’s first winner of the Tour de France.

However, for Wiggins to turn on those that question cyclists is wrong – if the sport is to be credible then it needs scrutiny and even some mistrust.

Throughout the years I have put Eurosport on and willed the eccentric Marco Pantani on; I’ve cheered for Scotland's David Millar; in 1997 I was pleased that Jan Ullrich finished ahead of Richard Virenque.

Those names are just four of the riders that are tainted by doping, their plights aided by a peleton that was happy to turn a blind eye.

They kept their counsel and rode alongside those that they knew were cheating and were therefore taking away their stage victories.

It's only natural for people to have suspicions when they see Oscar Pereiro named as winner after Floyd Landis wore yellow down the Champs-Élysées or hear of Andy Schleck being victor by default despite Alberto Contador sipping champagne on the way to Paris.

And that's all before you throw in the name of Lance Armstrong, a former icon that is now fighting to salvage his reputation.

In Millar’s fantastic autobiography Racing Through the Dark he talks about being drawn into the murky world of doping after becoming tired of resisting and being one of the few that didn't nip to the bathroom with their ‘washbag’.

The Scot is now playing a major role in spreading the sport's anti-doping message and has gone a long way towards redemption (like Dwayne Chambers, he will be a member of Team GB at London 2012).

Cycling has made impressive strides over the past few years but the questions will always be asked and they need to be answered, harsh as that may seem to Wiggins, Mark Cavendish and Cadel Evans.

They have enjoyed phenomenal success and in cycling that leads to raised eyebrows.

That must hurt after the hard graft and dedication they have put in to be at the top of their game.

Wiggins is clean but those that have gone before him have led to some fans questioning everything, and after being burnt before it’s hard to criticise them for that.