I had three posters on my bedroom wall when I was a kid: Dennis Hopper and Peter Fonda in Easy Rider; Barry Sheene; and Farrah Fawcett. Actually, Farrah was on the ceiling, not the wall. Well, you might as well be comfortable if you’re going to be staring at her all day.

The Barry Sheene poster was my favourite. He was on the winner’s podium with a fag in one hand, a bottle of champagne in the other, flanked by two gorgeous girls who were obviously going to get shagged by him later. As soon as I saw it, I thought: “That’s the life for me. I want to ride motorbikes.”

Evel Knievel was another huge influence. I was in the States when my dad [John Boorman] was directing a film there, at the height of Evel fever. It was my birthday and Jon Voight turned up with this big box of Evel Knievel toys. Even as a kid, I was in love with Jon’s wife, Marcheline Bertrand. She was the most beautiful woman I had ever seen.

I was the pageboy at their wedding — and the first male to hold their baby, Angelina Jolie. I suppose I should have that on my gravestone: “I was the first man to get his hands on Angelina Jolie.”

The man who got me into riding motorbikes was a neighbour in Wicklow, Ireland. His name was Tommy Rochford and I would regularly hear his two-stroke dirt bike screaming up and down the fields. He had a Maico 400, which was the dog’s cock of dirt bikes. It was known as the “ankle-breaker” because it could give you a serious injury if you weren’t used to kick-starting it. I was 9 or 10, way too small to ride it properly, so Tommy started it up, stuck it in first gear and lifted me on to the saddle. I set off round the field, fell off immediately — and was completely hooked.

I got my first motorbike a few years later. It was a Yamaha DT100, and I saved up for it by being an extra in films. In The First Great Train Robbery, there’s a scene where Sean Connery is going into court, and a young boy is waving at him from up a lamppost. That’s me, earning the money to buy my first bike.

I needed an off-road bike, because I wasn’t old enough to take my test.

That didn’t stop me going out on the road, though. One night me and a couple of mates were bombing along the country lanes in Wicklow. The back light on my bike was smashed up, but things like that don’t seem to matter when you’re that age, do they? We came steaming round this corner and there was Garda Jackson. He’d been watching us from a distance, and he knew one of us was riding without a rear light. On top of that, I was underage, had no licence, no insurance, no MOT. He was furious.

By the time I got back home, my dad knew all about it. He just handed me the Yellow Pages and said: “Better get yourself a good lawyer. You’ve caused all this trouble — you get yourself out of it.”

I was dyslexic — I couldn’t even spell lawyer. Of course, Dad was just letting me stew for a bit, to make sure I’d learnt my lesson. He and Garda Jackson worked something out later and I promised I’d never do it again. That promise lasted for about three days.

Motorbikes look so utterly gorgeous. They are almost addictive. Like Farrah Fawcett, I could stare at them all day. Cars don’t have the same effect. I own a car, a Toyota Prius, but that’s something you have to do. A bike is different. Owning a bike is a lifestyle choice.

I made that choice as soon as I jumped on Tommy Rochford’s Maico 400.

Travelling by bike is nothing like travelling by car. When you’re in a car you’re cocooned in your own little micro-climate. What’s going on outside doesn’t really bother you. But on a bike you’re in touch with the elements; you can’t escape from rain and snow, wind, mud and dust. When we made Long Way Down, Ewan and I would arrive at some African village and we’d be caked in dust and mud. As we rode into the village you got the feeling people wanted to mother us: “Look at those poor souls. Let’s give them a cup of tea.” The crew would arrive, step out of their air-conditioned cars and, well, it just wasn’t the same.

God knows how many bikes I’ve owned and sold. My main ride at the moment is a BMW GS1200 — the same model that we did the trip on. I have also lost count of the times I’ve crashed. I broke both hands when I was doing the Dakar Rally in 2006, but I still managed to ride a further 450 kilometres.

I was at the Nurburgring in Germany a few years ago, taking one of my bikes round that gorgeous 16-mile track. This bloke was flying round it. Really tanking it. I got chatting to him and he said: “Follow me round.” Nurburgring is a very difficult track, but he was showing me the ropes. After a while, he just shot off into the distance. Later, I saw him in the paddock. He took his helmet off — and he must have been 70. I just thought: “God, I hope that’s me one day.”

Long Way Down airs on the National Geographic channel on July 1, at 9pm

Interview by Danny Scott.

Portrait by Gino Sprio

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