Ted Simon is one of those men who dare to do what other men only dream of doing. In 1973, at the age of 42, he threw it all in and drove around the world on a Triumph motorbike. Starting from Dorset, his 64,000-mile journey lasted four years. “I never thought I would do something like that,” he says, “I’d never even ridden a motorbike before.”

The resulting account of his trip, Jupiter’s Travels, became a cult classic, a kind of Zen and the Art of Motorcycle Maintenance for a new generation of young men who dreamt of leaping on their choppers and zooming off into the great unknown.

He even inspired one biker to take a break from Hollywood stardom: after reading Simon’s book Ewan McGregor decided to do have a go along with his mate Charley Boorman.

Once in a lifetime would be enough, you might think, but in 2001 when he was on the brink of turning 70 Simon decided to retrace the steps of his first journey and ended up doing 59,000 miles through 48 countries on a BMW.

His reflections on a changed world echo the theme of Jeffrey Sachs’s Reith lectures. On almost every measure he found the world a less safe and welcoming place than a generation ago. A beach in Thailand that Simon had had to himself for a week on his first trip was now a nightmare of concrete and tourists. Tiny villages in Asia and Africa had ballooned into shanty towns, their inhabitants as poor as ever.

His new book, Dreaming of Jupiter (Little, Brown), is a wake-up call for anyone who still dreams of zooming across continents, sleeping under stars, discovering beautiful empty beaches and being warmly welcomed by local tribes. That dream has had its day.

The new trip was a catalogue of nightmare traffic jams, battles with border control bureaucrats, struggles to avoid potholes, mechanical breakdowns, broken bones, falls into ditches and encountering indifference from the locals where there was once the warmest of welcomes.

“The world has shrunk and is starting to look the same wherever you go,” says Ted. “On my first trip I would ride into a small village in Sudan or the Middle East and they would feed me, fuss over me like I was a pop star. This time around no one bothered — they’ve seen too many blokes on motorbikes.”

But if the novelty of seeing a man on a motorbike has worn off, he himself must be at least partly to blame. “I get e-mails all the time from people who are planning to go around the world and want to know how many toothbrushes to take,” he says.

“I do regret that my son will never be able to dance with the Turkana [the Kenyan tribe] as I once did, or that China has lost its mystery, that it is possible to travel from one end of Africa to the other without seeing a wild animal that isn’t protected, and all the empty beaches I once loved are full.”

He is most worried by overcrowding. “I saw it most dramatically in Brazil. There were a 100m people when I first went and now there were 170m when I went the second time. Even in the 1970s Brazil couldn’t support all those people. It’s creating more poverty as more people want what we in the West have.”

Yet he is keen to to emphasise that his journey wasn’t all gloom and doom. “I had many wonderful moments — finding old friends and seeing so many beautiful sights. I also fell in love with an amazing woman.”

For Ted the world may be going to hell but he still finds individuals who are inspiring. “They make it worth getting on your motorbike. Really, there are wonderful things to do and plenty of fine people to meet in the world and — even at 70 — you can still find love!”

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