A 20,000-mile round-the-world motorcycle jaunt should be enough to cure any midlife crisis. Which makes us wonder about Ewan McGregor. Three years after his circumnavigation of the globe—seen in the 2004 film Long Way Round—the Scottish actor got the itch again. This time, he and friend Charley Boorman set off from John O'Groats, Scotland, and rode 15,000 miles south to Cape Town, South Africa. The U.S. premiere of Long Way Down, the show chronicling their three-month adventure, debuts on the Fox Reality Channel August 2. We flagged down McGregor, 37, to talk about taking the action off-screen.

OUTSIDE: One trip like this is a novelty. Two is a pattern. Are you OK with being seen as an adventure guy?
MCGREGOR: Yes. I'm proud of what we did. We met people in Africa who were traveling because they'd seen Long Way Round. A lot of television is about nothing at all, whereas we took off on our bikes and shot our experience. We hope it encourages people to do like-minded things.

Ever wish the cameras weren't there, with all the time you spend in front of them?
There was only one camera, and the cameraman was riding with us. It's not as intrusive as you might think. But there were sections of the trip where I wished we could've taken more time. We met bikers who'd been traveling for many years.

What's the culture shock like between Sicily and Africa?
I expected the port in Tunisia to be something out of an Indiana Jones movie. In fact, it was just a standard customs office. We got delayed by some officials who wanted vodka.

What kind of reception did you get in smaller villages?
People are kind to you when you're on a motorcycle. They appreciate that when it's raining, you get wet.

What about that sandstorm in Libya?
That was quite exhilarating, really. You have to block off your vent or the sand will blow inside your helmet and sting your eyes. The bike in front of you–that's all you see. That day, we did 500 miles. It was like riding through brown sugar.

What's your hygiene like on a trip like this?
You lower your standard, but you get by. You always come across rivers. But you don't want to jump into just any one, because there could be crocs. We also carried baby wipes. That's a handy way to keep clean.

Any tips on maintenance in Africa?
The key is to take as little as possible. That's easy for me to say, because we had a couple of vehicles following us with camera equipment. But you want the bike to be light. Also, in an emergency, you need to be able to fit an inner tube. Bring a spare that can work on the front or rear. And tire irons.

If a bike breaks down, who rides in back?
Whoever's bike has broken down. There's an unwritten rule that you always ride your own.