Mark Cavendish saunters through the chic minimalism of the St Martins Lane hotel in central London with a messy grin plastered across his face. He waves cheerily and shouts "Hello, mate," in a gravelly Isle of Man bark. "Great to see you again," he says, stretching out his hand and sounding nothing like the bolshiest and most driven man in British sport.

A year ago, when we last met, on the eve of his second Tour de France, Cavendish was blunt and fierce – promising he would win at least one stage as well as an Olympic gold medal in Beijing. Cavendish revered the gruelling demands of the Tour far more than the populist appeal of the Olympics, and he ended up winning four stages in France. He was denied even a medal in Beijing, where he was furious with the British track team and Bradley Wiggins, his partner in the Madison, but Cavendish has moved on.

Apart from winning three stages at this year's Giro d'Italia he also entered his first classic in March, the majestic Milan-San Remo race, which he won in a brutal sprint after riding with grit over some steepling climbs. He will begin this year's Tour, starting in Monaco on Saturday, with his position as the dominant sprinter in world cycling underpinned by an aura that amuses him – and helps explain his good mood.

"It's so ironic that the better you get the easier it becomes to win," he says with a throaty chuckle. "The space I'm now being given by the peloton is ridiculous. They're looking over the shoulder to make room for me and that's the biggest irony of all. Instead of plotting ways to close me down it seems as if, when things get tight in the last 'k', someone will see me and move over so they can wave me through. I'm thinking, 'Shouldn't you at least try to beat me?' To be honest, it can get boring."

A year ago Cavendish seemed to burn with righteous indignation that there were still supposedly informed people within cycling – or "dickheads" as he more pithily described them – who doubted his self-proclaimed status as the fastest man on the road. There is no debate now; but the peloton might be stirred by a laughing Cav suggesting that beating them all so consistently is becoming "boring" .

Cavendish shrugs. "I'm not getting bored with cycling or winning – I love it. But I need to give myself new targets all the time. And so I have bigger and bolder aims now. I've got everyone's respect, but I need to keep it interesting."

In the restaurant the slight but intensely coiled figure of Cavendish declines all offers of breakfast or even a jag of caffeine. He's too busy talking. "Part of what makes me so successful," he says, eyes suddenly blazing, "is that I never settle on anything I've achieved. I always set my next target."

Cavendish starts with deceptive simplicity when listing his new ambitions. "My short-term targets are clear. I want to reach Paris this time," he murmurs in reference to the fact that, after winning four of the first 14 stages last year, he pulled out of the Tour in order to prepare for the Olympics – which was why he was so angry when that commitment could not be matched by an exhausted Wiggins, who was trying to win his third gold medal.

"I also want to win green," he says, referring to the jersey worn by the Tour de France cyclist who wins most points as a sprinter. "This year, realistically, it's only a possibility. Next year, and the year after that, the green jersey is a probability.

"But the dream can become a target because the way the Tour is set out this year it's basically either a sprint or a mountain stage. Green is usually about consistency but this year it's different. So that bodes well for my chances. If you normally go for green you have to sprint more conservatively – you have to be content with fourth and fifth places. I don't like that. I always go for broke. It's win or nothing for me. But, maybe, this year the green on Tour might suit me. It could even come without me actually targeting it. That would be fantastic."

The extent to which Cavendish reveres cycling history can be heard in his evocative description of his Milan-San Remo victory. "When you grow up as a cycling fan, as a connoisseur, you understand why that race means more than the Tour de France. You appreciate the classics the most. For any young rider even competing in the San Remo is one of the biggest things – but to win it is beyond emotion. You can't put it into words."

Cavendish, briefly, covers his face. He looks out from behind the slatted windows of his fingers and says, huskily: "I still sit back and go, 'Fuck, I can't believe I've won it. It's just beautiful.'" His win was marked by a cry of desolation from Heinrich Haussler as Cavendish flashed past him at the death. "It was sheer anguish because he knew I'd beaten him by 15cm."

That reflection prompts another sincere tribute from Cavendish to the efforts of his team-mates at Columbia. "We've got an amazing group who all want the same thing. In our team we've got so many different nationalities and that tells you everything. Usually, if it's a German or French sponsor they want lots of German or French riders. For the brand it makes sense, but you're not going to get much coverage if you're unsuccessful. Our team prides itself on ability rather than nationality."

That endorsement clashes with the aims of the UK cycling gurus, led by Dave Brailsford, trying to compete next year in the Tour with a wholly British Team sponsored by Sky. Cavendish smiles thinly when asked if he would feel any additional delight should he, one day, win Tour stages in a team full of British cyclists. "No. If I was a mediocre sprinter I might feel that – but I'm the fastest in the world. I'm the most in-demand sprinter in the world. My nationality is irrelevant. Whenever Team Sky is mentioned now, I'm mentioned – but I'm not in demand because of my nationality. I'm in demand because of my ability."

Could anything entice him to leave Columbia for Team Sky? "Look, if the British team, in 10 years time, is the best team in the world, I'll be there. In two years time if a French team is the best team in the world, I'll be there. But at the minute Columbia is the best team for me. I can guarantee that I'm going to enjoy myself and have a successful career with them. So all this talk about a British team is irrelevant to me. Politically, I'm not that interested in nationality. For me it all boils down to ability."

In his absorbing and often riveting new book, Cavendish trashes the contribution of some former leading members of British cycling – in particular, Simon Jones, acclaimed as the UK's coach of the year after the 2004 Olympics. "He was a dickhead and all their scientific analysis of riders is complete bollocks when it comes to me. They kept telling me I wasn't hitting the numbers but look what's happened since. I couldn't give a fuck about Simon Jones."

With more warmth, he describes Brailsford, the feted performance director of British cycling, as "a media darling". He is also amused at the way in which Britain's Olympic gold-medal winning track cyclists are so heavily reliant on the sports psychologist Steve Peters – who has done so much to ease the often tortured psyches of Wiggins and Victoria Pendleton, and even Chris Hoy. "I like Steve. But all that stuff about 'taming your inner chimp [of negative thought]' is hilarious."

What does Peters make of Cavendish's self-belief? "I think he's quite fascinated by me. He talks a lot about me. These are things about self-confidence people usually have to learn but I've always done them instinctively."

Who else in cycling has that conviction? "Lance Armstrong."

As he returns to the Tour, Armstrong's clouded reputation in France will raise the perennial controversies surrounding doping and cycling. But Cavendish is entranced by the seven-time winner of the Tour. "When I first read he was saying all these great things about me, I was blown away. Any kid who grew up wanting to be a cyclist would have dreamed about being recognised by Armstrong one day. But now I speak to him at races – I can text him. It's pretty surreal.

"Before the Giro I still had that awe thing but we spoke most days and it just got warmer and warmer. Now it's just great. He's going to get a lot of flak in France and I feel for him. But he's going to concentrate on the race because I know he still wants to win the Tour."

Cavendish will be sprinting after the green jersey, rather than the yellow, and also revelling in the publication of his book. "Outside of cycling, there are three things I've always wanted – a boat, even if it's a paddling boat, a spiral staircase in my house, and a book about me. I've only got the last one so far, and I'm proud of it. I know so many people fluff their lives up in a book to make themselves look good or to make people feel sorry for them. But I just want to be frank and to the point. And I want to win bike races. I've always said I don't want to be known for my name. I want to be known for my achievements. That's all that matters."

Mark Cavendish's "Boy Racer" is published by Ebury (£18.99)