Whether racing on the Formula One circuit or testing the limits of jet-skis, snowboards and other extreme sports, Lewis Hamilton loves the fast life on and off the track.

"I'm at my most comfortable when I'm going fast," says the 30-year-old star of the Mercedes AMG Petronas team, hours before racing at the Singapore Airlines Singapore Grand Prix.

"When I drive, when I get to high speed, I feel like everything slows down for me and I can do anything."

He pauses in thought.

"Also, when I was a kid, I got bullied. There were bigger kids pushing me around, there were smarter kids, and I think when I was driving fast, no one was as strong as me at that point.

"No one can touch me when I'm fast. I can manoeuvre wherever I need to go."

It is a strange admission of vulnerability on the floodlit F1 tracks from a two-time world champion who is famed for his self-confidence.

He dismisses pre-race rituals as rubbish ("As a kid, I had some lucky boxer shorts. My mum shrank them.").

His music player is filled with songs he writes and records for himself.

Fielding question after question about whether he feels the pressure as defending champion to complete a hat-trick, he only smiles serenely.

"What is there to add pressure? I want to win. I want to succeed. All the other noise is irrelevant. It all adds up to what I'm trying to do anyway."

Twice in the interview, organised by team sponsor Hugo Boss, while a team of engineers only metres away races against the clock to soup up his car, Hamilton says: "In honesty, I feel like I can do anything I put my mind to."

It is hard to dispute this from someone who became Britain's youngest karting cadet champion at age 10, three years later was signed by McLaren and took his first world championship title at age 23.

This year he has been ranked the richest sportsman in Britain by the Sunday Times of London.

Forbes puts him 55th in the list of world's richest celebrities with an estimate of US$39 million (S$55 million) in earnings.

But he got his start in a working-class housing estate in Stevenage, Hertfordshire, and his father Anthony worked several jobs to ensure his son could follow his passion for karting.

It was Anthony who gave Hamilton a taste for speed.

"We used to go to an abandoned carpark and I'd sit on his lap and he'd let me steer, so I loved driving from a super early age."

Hamilton is descended from West Indian emigrants to Britain - his mother Carmen is white and his parents divorced when he was two - and is the first mixed-race F1 world champion.

"We're the first family of colour in the sport. When we were young and going for races, everyone would stop and look at us, it was a white-dominated sport.

"We went through a lot of difficult times at races. We kept our heads down and did our best, we beat people and it was the greatest feeling."

Yet he gives himself maybe seven more years in the field.

"There's something beyond Formula One, I'm trying to discover what that is."

Might it be acting? He had a cameo as himself in the 2011 Pixar cartoon Cars 2 and another in the Ben Stiller comedy Zoolander 2, slated for release early next year. "I don't know if I can act," he says.

Might it be music? Tabloid rumours have it that Kanye West and Jay-Z are enthralled by the tracks the sportsman writes and records for himself, and Hamilton does say he spent the flight into Singapore working on his latest effort.

"It is a song about a girl, but not really love," he says.

"I think if one day someone takes my song and does something with it, it would be kind of cool to be known as a writer, but I don't have any plans. I don't even know if I'd give them to anyone."

It is hard to pin him down to specifics because, as he says: "I'm super spontaneous, I'm always last-minute changing, making decisions to do things."

Such as giving up on his barber of 12 years in London to find a stylist who would turn him blond before the Italian Grand Prix earlier this month.

"I've experimented with getting tattoos, I've experimented with dress styles, I was, like: 'I'm going to try and change my colour,' and I did and I loved it," he says.

He lives in Monaco, but often visits family in Britain and friends in America.

The most popular F1 driver on social media, he often shares selfies and photos of his travels with his 2.9 million followers on Twitter and 1.7 million on Instagram.

Many show him running - "It's the only time I really get to sightsee" - or walking his two British bulldogs, Roscoe and Coco, found online while he was waiting backstage for his ex-girlfriend, former Pussycat Doll Nicole Scherzinger, to film episodes of TV contest The X-Factor.

Hamilton is not looking for a new partner right now, but says he would one day want to have a family and children with someone "brought up with good values", meaning: "good with kids, humble, has her feet on the ground. Have to be caring, a loving person, polite, carry herself well. More beautiful inside than outside."

Constant travelling puts pressure on a relationship and he knows he will have to slow down some day. Just not now.

"Right now, I'm as fast as you could possibly be so I don't see me slowing down. My mind, since I was very young, has been set on being the best Formula One driver in the world and that's what I'm still working towards," he says.