There is one novel I reread every couple of years: Voltaire's Candide. It's short, which I like, and the protagonist has the simultaneous qualities of astonishing naiveté and grim determination that are invaluable in a traveller, but increasingly rare. I often thought of Voltaire's masterpiece while reading Rob Lilwall's epic account of cycling home from Siberia, a place he heads off to in October with equipment that includes a pair of £10 Royal Mail over-trousers, a whistle that stuns ferocious dogs, and a secondhand tent that he puts up for the first time in -20C. His route is the same one that Ewan McGregor and Charley Boorman tackled on motorbikes, but there is no television crew or back-up team for Lilwall.

The man starts with a confession: he's a Christian - and later confirms he prefers to stay with priests or nuns. I almost gave up there, but the honesty makes for compulsive reading: he farts on Russian live radio and gets the giggles, he camps in disabled toilets in Japan - and observes that they are cleaner and more comfortable than Russian hotels. When he is mugged at gunpoint, he has violent revenge fantasies, then feels guilty and prays for his attackers.

His disarming, open-faced bravura gets better and better as the book progresses. In Papua New Guinea, a place he decides to cycle around, he is chased by drunken men brandishing cudgels. Afterwards he wonders if perhaps he had pre-judged them and they were only being friendly. Candides were ever thus. Some of the conversation, totally convincing, is worthy of the great Voltaire. In Siberia, warned repeatedly against camping in the forest because of wolves, he questions one particular host more closely. Has he ever seen wolves?

"Never," he said.

"Have you ever heard them howling?" I asked.

"No."

"Do you know anyone who has heard or seen a wolf in these parts?"

"No, but you should not camp; there are wolves!"

He camps, of course, and neither sees nor hears wolves. The incident does not bring on reflections about unsubstatiated beliefs, but this is Candide writing, not Voltaire. On and on he goes, pedalling furiously around Australia, up the Malay peninsula and through to China where, in a cheap hotel in a town whose name he does not know, he confesses to himself that he has never been happier. I believed him. Lilwall has a wonderful ability to inspire trust in his readers - the same kind of trust, I imagine, that he inspired in his many benefactors en route: the book is truly a paean to human hospitality.

Ignoring doom-sayers and newspaper headlines, trusting instead in his own experience of human kindness, he pedals into regions that most people would avoid, notably Afghanistan. There he observes that Nato troops do not wave back at him; then, catching sight of his shaggy hair and ragged clothes, he realises he resembles a local more than an eccentric geography teacher from west London. The innocence and simplicity never fail: when a village fanatic refuses to shake his hand, he rides quickly away, reflecting: "It had been very rude for that man to refuse my hand and I was alarmed to have no idea what anyone was saying."

Three years after setting out, he cycles up his parents' road and his mum greets him: "Welcome back." Perfect. I'm not sure Rob Lilwall knows it, but he has penned a two-wheeled classic. I wanted to rise up singing and strap on my bicycle clips.

• Kevin Rushby's Paradise: A History of the Idea That Rules the World is published by Robinson. To order Cycling Home from Siberia for £9.99 with free UK p&p call Guardian book service on 0330 333 6846.