Sub-Saharan athletes already overwhelmingly dominate distance running. Now men from Kenya, Rwanda, Eritrea and beyond are taking to the saddles of road bikes, with jaw-dropping results. While British and European teams fixate on marginal gains made through improved technology, an untapped continent of brilliant, naturally gifted cyclists is ready to blow them out of the water.

The day before Bastille Day in 2011 was a generally unremarkable one in the Tour de France. The riders started near some coalfields in the Midi-Pyrénées, whooshed past the Toulouse-Lautrec museum and finished in a rainy bunch sprint that Mark Cavendish won before effusively thanking his team-mates.

But there was a moment that stuck out: as the peloton rolled along, a black man in mirrored shades, as relaxed as you like, pedalled to the front of the race.

I watch a borderline-sociopathic amount of cycling on television, and he was the first black rider I’d ever seen in a European cycling race. Even commentator Phil Liggett, who has been covering the Tour for 40 years, became momentarily ruffled, referring to the “coloured cyclist” and inspiring a virtual mailbag of complaints from viewers.

Later, while Cavendish tweeted an update on his saddle sores, the online chatter began. On the Acting White Acting Black blog, James C Collier wrote: “Newsflash!!! I just saw young Yohann Gène up front in stage 11 protecting the yellow jersey of his team-mate Voeckler. That ain’t no tan — that’s a brother! Awesome!!!”

Hard to believe, but Yohann Gène of Team Europcar was, indeed, the first black rider of any nationality to compete in the world’s greatest cycling race. He was born in Guadeloupe and was scouted in 1997 when Jean-René Bernaudeau, a professional rider from the Eighties who is now the eccentric boss of Team Europcar, was on holiday in the West Indies.

There is a proud history of cycling in Guadeloupe and Bernaudeau decided, almost as an experiment, to take a pair of 17-year-old riders back to France.

Gène’s debut in the Tour de France more than a decade later wound up being a high-profile one: his team leader Thomas Voeckler gurned away in the maillot jaune for 10 days and Team Europcar could often be found at the front of the peloton huddled round Voeckler like worker bees defending their queen.

“I am French, so the Tour de France is something special,” Gène said. “It gives me wings.”

Bernaudeau was ahead of his time in acknowledging that the European dominance of the great cycling races was coming to an end. It was not a comfortable realisation for many French fans. Since the Tour de France was first contested, in 1903, the pool of winners had been remarkably select.

In fact, until 1986 when the American Greg LeMond won — that his name sounded almost French was but a minor consolation — the Tour de France had always gone to European riders.

France accounted for 36 successes, Belgium 18, Italy eight and even Luxembourg, hardly a sporting powerhouse, had claimed four victories. Europeans, the conventional wisdom had it, prevailed because they best understood the tactics and the culture of cycling: the key qualities were physical durability, mental and moral strength, and what the French called <rage>: a desire to succeed. (It’s also their word for rabies.)

LeMond, however, was not an aberration; he was an outlier. Since then, the winners of the Tour de France have started to come from all sorts of odd places with no historic links to cycling: Ireland, Denmark, Germany, Australia and — sacré bleu — the Dibdin House estate in Kilburn, north London. (I’m sure there was another American who won a few times too, but could find no corroboration on the internet.)

The sport became a financial, technological and pharmacological arms race. Not so long ago, teams were funded by parochial French sponsors (Farm Frites sticks in the mind); now the pockets bankrolling the sport belong to Russian oligarchs, hearing-aid billionaires and, of course, the Murdoch dynasty with Team Sky. Defence contractors and Formula 1 teams created cycling-specific innovations, from the sleekest uniforms to the lightest helmets.

Technology, though, has its limits. If cycling teams are prepared to spend millions investing in the best kit and state-of-the-art machinery, it would make sense to have the most biologically gifted athletes on the planet riding the bicycles. Hard to believe, but that might not be a bloke with long sideburns and a man-crush on Liam Gallagher.

The list of countries whose riders have never featured in the Tour de France roll call turns out to be surprisingly long: there are 500 million cyclists in China, but they have never produced a top-level professional. It is Sub-Saharan Africa, however, that is a particularly glaring omission.

Black Africans utterly dominate distance athletics — of the last 10 London Marathons, eight have been won by Kenyans, two by Ethiopians — and many would seem to have all the physiological traits (huge lungs, spindly but powerful legs) to do well in cycling.

Why had nobody thought to stick the best distance runners on a bike?

Turns out, they have. In 2010, I went to my first Tour of Rwanda. Even its name sounded like a punchline. “I thought it was a joke,” admitted Simeon Green, a British professional riding for a lower-tier French team, CA Castelsarrasin. “Like the ‘Tour of Afghanistan’.”

But the racing was relentlessly serious: there is scarcely one flat road in all of Rwanda and, every day for two weeks, the home riders did battle with lanky Eritreans and powerful Kenyans on slopes that were Alpine in severity, if not length.

Millions of locals stood by the roadside and screamed as the peloton flew past like an unexpected storm: a kaleidoscope of flashing colours. Some of their equipment was ancient and tactics were at times non-existent, but as pure athletes, these riders were inescapably the real deal.

There are two visions for the future of cycling as it wobbles unsteadily after Lance Armstrong’s drug bust. In one of them, the arms race escalates and rival teams pump in more and more money to overhaul Team Sky. This would not favour African riders.

But another view imagines a reformed, more wholesome sport; one that is perhaps cleaner than ever. Teams would be forced to scour the globe for riders who naturally have the athletic qualities that previously could only be created with doping programmes.

Then it becomes a numbers game, and Africa always wins: by 2100, there will be more 18-to-25-year-olds on the continent than in China. It will be the biggest sporting mass population in the world.

“It’s a new frontier for cycling,” says Jean-Pierre Van Zyl, a former track champion who is now head of the International Cycling Union (UCI) World Cycling Centre in South Africa.

“With everything going on in professional cycling, Africans have no idea of the systematic doping and all that nonsense that’s been going on in Europe. This will be the saviour of cycling.”

In Rwanda, I discovered that some people had already made advanced plans in different parts of the continent to bring about an African cycling revolution. These pioneers divided into three broad categories: the first knew everything about cycling, but nothing about Africa; the second was well-versed on Africa but had only rudimentary knowledge of European cycling.

Then there was Nicholas Leong, and he didn’t seem to know that much about cycling or Africa.

Leong, a commercial photographer from Singapore, was holed up at home in 2006 with a particularly spiteful splinter in his foot. One day he started to wonder if distance runners might make good cyclists and he thought he would go to Kenya to find the answer — a mid-life crisis might have been involved too, he concedes.

He booked a plane ticket to Nairobi for the evening after the 2006 Singapore Marathon on a hunch that the runners would be on the flight. At the airport, he walked up to group of skinny black Africans; out of the first 15 runners to cross the line that morning, 13 had been Kenyan.

He asked, “Who’s the guy who won the marathon?” Amos Matui, the smallest of the bunch, presented himself. Leong said, “OK, I’m following you home!”

Leong had never been to Kenya before. Everything he knew about cycling had been gleaned from watching videos of the Tour de France. “I’m like the guy who sits there on Saturday and watches Manchester United and has watched Manchester United for 30 years, so he thinks he knows everything about the game,” he says.

Leong wound up in Iten in the highlands of the Great Rift Valley. There are officially only 4,000 residents of Iten, but many of them have gold medals and world records to their name. The 800m runner David Rudisha, star of the 2012 London Olympics, went to school in the little town and Mary Keitany, winner of the last two London Marathons, lives there now. The problem Leong found in Iten was that none of the runners wanted to swap their spikes for bikes. Prize money for a major city marathon is typically around $100,000, while even $10,000 for a lower placing is a life-changing amount. Leong had in mind a monthly wage of something closer to $100.

Eventually he found Zakayo Nderi, a shoeshine in nearby Eldoret; he would wake up each morning at 5am to ride his bike, a single-speed Black Mamba roadster that weighed nearly 20 kilograms. Leong offered to train Nderi and three other riders in Singapore on proper racing bikes for a couple of months.

At the end of that period, he picked a pair of them — Nderi and bicycle-taxi rider Samwel Myangi — and in 2008 headed for the Alpe d’Huez, the most celebrated climb in the Tour de France.

It was a stunt, mostly designed to raise awareness and boost fundraising, but it turned out to be a revealing experiment, as well. The night before, Nderi dreamed of slaying a lion; the next day, a Thursday morning mass-start event, he scampered up the 21 famous hairpins in just 42 minutes 10 seconds.

That was only three minutes outside Lance Armstrong’s time in the 2004 Tour de France. If Nderi had been racing that day, he would have placed in the top 20.

Not bad for someone who had never ridden a bike with gears before Leong showed up.

Jock Boyer is decidedly not that guy who sits at home and watches Manchester United on Saturdays. He’s more like Eric Cantona, in fact.

Boyer and Leong are absolute opposites in most ways: Leong is a roly-poly man with irrepressible enthusiasm; Boyer is lean and sinewy, and has a manner that people often interpret — not without justification — as rudeness. In 1981, Boyer became the first American to ride in the Tour de France; two years later, he finished 12th.

If anyone knows what it takes to succeed as an outsider in European cycling, it’s him.

When Boyer first came to Rwanda in 2006, he had no clue where it was; he had to look it up on a map. He knew nothing about the genocide of 1994, in which up to a million Rwandans, out of a population of eight million, were slaughtered in 100 days.

Boyer was looking for a clean start of his own: he had recently come out of jail in the United States after serving eight months for lewd acts with a minor. He started riding with a group of the best Rwandan cyclists; Boyer was 51, but he weighed the same as when he competed in the Tour de France and he had just won the Solo Enduro category of the 2006 Race Across America, one of the world’s toughest long-distance events.

However, day after day, Boyer struggled to keep pace with the Rwandans on training rides. He was stunned. He had brought with him a CompuTrainer, which fixed to the back wheel of a bike and allowed you to test a rider’s power output and their anaerobic threshold, an essential marker for endurance athletes.

Their results were off the charts, particularly a brilliant young climbing specialist called Adrien Niyonshuti. With Zakayo Nderi’s ride on the Alpe d’Huez, there was mounting evidence that the best African riders could hold their own with the top Europeans.

More than the quality of the riders, however, Boyer recognised an innate resilience. He might have been ignorant about Africa, but racing his bike for 250 days a year had made him an expert on pain.

Boyer quickly learned that there was very little you could tell these Rwandans about hardship. All of them had lost friends and family during the genocide; five of Niyonshuti’s brothers and one sister, and more than 40 family members, had been killed.

None of them had houses with either electricity or running water; some had been street kids, living off food they scavenged. They would set out on a training ride, no food in their pockets, no idea how long they would be out on the road, and just put their heads down and spin.

“If Team Rwanda had not come, I would not be riding a bike, because it was not easy,” Niyonshuti tells me. “No spares, no bike, nothing. I remember that in 2005 I get a problem with the tyre and I could not get a tyre for my bike in the country. Jock has helped me a lot. Sometimes I call him my dad, because if someone helps you for nothing, he looks after you all the time, you have to give him respect.”

The selflessness of Boyer’s motives can be questioned — there is a disconcerting whiff of neo-colonialism about the authoritarian white man who arrives in Africa and sets the locals to work.

But Team Rwanda has indisputably changed lives: riders are paid a monthly stipend, and many have been able to buy houses and cows: the traditional gift for your bride-to-be’s family.

They were also starting to achieve very respectable results in international races. Niyonshuti was taken on by the biggest team on the continent, MTN-Qhubeka, based in South Africa, and he raced for Rwanda in the cross-country mountain bike event at last summer’s Olympics.

“I’m sincerely convinced that the future winners of the Tour de France are here in Africa,” Boyer says. “It’s just going to take time. It could be five years, it could be 10 years, but it will happen.”

The best cyclist in Africa is, however, from neither Kenya nor Rwanda. He is an Eritrean called Daniel Teklahaimanot. Eritrea — a small sliver of land opposite the Red Sea that is occupied by five million people — has one advantage that Kenya and Rwanda do not: an established cycling culture.

A long-time colony of Italy, in Eritrea the Italians had left behind their love of bicycles, along with streets of incongruous modernist architecture and a passion for coffee.

There are around 200 full-time professional cyclists in Eritrea and, unlike the rest of the continent, there are hard, technical races every week of the year. Spectators pay to watch, and the larger teams have boisterous fan clubs. The Tour de France is shown each year — in full — on state television.

Until recently, no one knew that Eritreans were mad about cycling, but then there is much we don’t know about the country. On the World Press Freedom index, Eritrea currently ranks 179 out of 179 countries. That’s behind North Korea, Iran and Turkmenistan.

There is no independent media in the country at all, and no foreign correspondents are based in its capital Asmara. Reporters Without Borders calls it a “black hole of information”.

The country has always had conscription, but since 1998, when a border dispute was restarted with Ethiopia, military service has been open-ended. Some soldiers are said to be in their seventies.

Being a member of the national cycling team — and other sports teams — is one of the few legal ways to avoid conscription. Or at least to defer it; you might still have to do a stint at the end of your career. It also provides a rare opportunity for foreign travel — and potential escape. Eritrea has one of the highest defection rates in the world, perhaps second only to Zimbabwe.

Among the diplomatic cables unearthed by WikiLeaks in 2010 is one titled “Eritrea’s squabbling colonels, fleeing footballers, frightened librarians”. It tells the tale of how the entire Eritrean national football team absconded in 2009 during a regional tournament in Kenya.

It is like Escape To Victory, without Sylvester Stallone encouraging the players to come back to play the second half.  “Only the coach and an escorting colonel reportedly returned to Eritrea,” writes United States ambassador Ronald K McMullen. “(One wonders why, given their likely fate.)”

Teklehaimanot is one of the few Eritreans to make it out of the country with permission. In January 2009, he was sent to the UCI headquarters in Aigle, Switzerland, for a prolonged period of training.

Soon after he arrived, the coaches found that one of his legs was shorter than the other; it can be corrected, but it is not ideal for a professional cyclist. He had never been near a dentist in his 21 years so his teeth were a graveyard.

But the major issue was his heart: when he fully exerted himself on a bike, his heart rate spiked to 260 beats per minute. He was diagnosed with tachycardia, an abnormally rapid heart rate that is dangerous and, for a sportsman, life-threatening. There was a chance he would never ride a bicycle again.

There was one more thing they discovered in the physiological tests. Even with tachycardia, Daniel’s power output and his ability to sustain intense effort exceeded almost anything the coaches had ever seen.

In fact, only one UCI graduate came close: Chris Froome. Within five years of leaving, Froome, the Kenyan-born British cyclist, was runner-up in the 2012 Tour de France and is now a favourite for this year’s race.

The operation to address the tachycardia went without complication and Teklehaimanot was soon winning every race on the African circuit. He is tall, just over 6ft 2in, and has 3 per cent body fat, which is about the amount you see on competition bodybuilders. He can climb, time trial; everything, really.

His talent was too big to be ignored by the major cycling teams and in 2011 he was signed by GreenEdge, Australia’s answer to Team Sky. He was paid €33,000 a year, minimum wage, although it was preferable to the $20 a month he would get in the Eritrean military.

Teklehaimanot was not selected for the 2012 Tour de France, that was never the plan, but he was picked for the nine-man GreenEdge team for the season-ending Vuelta a España, Spain’s most important race and one of the big three on the cycling calendar.

When he rolled down the start ramp in Pamplona for the opening team time trial, he became the first black African to compete in a Grand Tour. In another glimpse of the future, Ji Cheng, a 25-year-old rider with the Argos-Shimano team, recorded the same distinction for China.

More significant than the historical footnote was Teklehaimanot’s performance. He raced hard and worked unstintingly for the team. At the beginning of the third week, he made it into a group of riders who had broken away from the main pack but crashed on a descent.

He was going 50mph and landed on his shoulder in a ditch, bashed up and bruised. He finished the stage last, in 182nd place, half an hour back. He was still suffering the next day and lost another 35 minutes.

But he reached Madrid to complete the race. (Ji Cheng also made it through, in last place overall, completing the event four-and-a-half hours behind the winner, Alberto Contador.)

Shayne Bannan, general manager at GreenEdge, was impressed with Daniel’s ability to suck up pain; much as Boyer had been with Adrien Niyonshuti. Life as a professional may not be easy, but it probably beats being conscripted to the Eritrean army.

“You don’t get where he’s got, leave your home country, come and live in Europe if you are not mentally tough,” says Bannan. “He is that, no question.”

The debate is now not if Daniel Teklehaimanot will race in the Tour de France, but when, and whether he will be the first black African. Bannan, not a man given to bombastic pronouncements, believes he could be a top-20 finisher, perhaps higher. This summer might be too early, but in 2014, he will be 25 and approaching his peak.

Last August, Jean-René Bernaudeau signed Teklehaimanot’s Eritrean team-mate Natnael Berhane to Team Europcar for this season. Berhane is a puncheur: a rocket on short climbs and with a lethal finishing kick, and Bernaudeau fancies he could take out a stage here and there.

Phil Liggett had better start brushing up on his pronunciations and terminology now. In South Africa, MTN-Qhubeka recently became the first African team to gain Pro Continental status — a rung below Team Sky and GreenEdge — and their aim is to compete in the Tour de France by 2015.

At present, their squad is 70 per cent African and includes Niyonshuti from Rwanda and a 21-year-old Ethiopian called Tsgabu Grmay, who might just have the greatest long-term potential of all the African riders.

“In 10 years’ time world cycling will be very different,” predicts Doug Ryder, team principal of MTN-Qhubeka. “The Americans had their time and the British are now having theirs, because Sky invested a lot at the Olympics, signing stars. But wait: Africa is coming.”

Across the continent, some very different programmes, all working independently, are converging on a moment in history. Eritrea has unparalleled strength in depth and is finally allowing its riders to gain international experience. Boyer has expertise and a bulging book of contacts to help Rwanda, and this year he is expanding his project into Ethiopia.

Kenya has neither of those advantages, but perhaps it has the most naturally gifted athletes.

Nicholas Leong’s unconventional approach continues: as coach, he has hired someone who knows even less about cycling than he does.

Still, Rob Higley, an Australian running expert, has worked in Africa for two decades and one of his protégés is David Rudisha. Zakayo Nderi is past his prime now, but stronger riders are coming through every year.

“It feels like an idea whose time has come,” says Leong. “You hear about Edison inventing electricity or the Wright Brothers inventing flight. But actually, if you’re a student of this stuff, you realise that at the same time there were two, three or four people working on the same idea and one of them succeeded.”

Everyone involved now accepts that it is not a simple matter of putting Africans on bikes and watching them go. For one thing, there are not enough bikes to go round. Rwanda has one of the fastest-growing economies in Africa, but still only one person in 40 can afford to buy the most basic, single-speed bicycle.

The terrible roads across the continent are another barrier to cycling success. But what is really holding back Africans right now are factors you might never think of. Boyer reveals that it took more than a year for him to teach his Rwandan riders to drink from a water bottle without slowing down. Team members are often laid low with malaria for a few weeks.

“I cannot think of anything, within my capabilities, that would have been harder than what we were trying to do here,” Boyer says, cracking a rare smile. “There might have been something — like teaching pool to pygmies, but I’m not a pool person. It was an impossibility.”

Not so long ago, Africans were not known for distance running. Then in 1968, Jim Ryun and Kipchoge “Kip” Keino lined up in the 1500m at the Olympics in Mexico City. Ryun was the corn-fed, all-American superstar from Wichita, Kansas, who had started running as a kid on his 4.30am newspaper round. Tall and lean, with a distinctive flattop haircut, he broke the four-minute mile shortly after his seventeenth birthday.

He entered the final in Mexico as the world-record holder, unbeaten at the distance for more than three years. More than the numbers, he just looked like an athletics champion. Sprinters could get by on raw explosive power, but longer distances called on cerebral qualities such as focus and discipline. The determination and stamina required, it was said, made it the domain of the Anglo-Saxon.

Keino was a policeman from Kenya who escaped a cheetah at the age of 12 by shinning up a tree and tying himself to a branch overnight. He had never beaten Ryun and his tactics in the final appeared either naïve or desperate. He sprinted from the gun, soon establishing a lead of 12 metres. Keino was running suicidally fast, but instead of Ryun reeling his rival back with his famed finishing kick, the lead edged out to 15 and finally 20 metres, the widest margin of victory in that event in Olympic history.

Afterwards, Ryun was attacked in the press: his defeat inexplicable and somehow inexcusable. He briefly retired, though he was only 21. “Some even said I had let down the whole world,” he recalled. “I didn’t get any credit for running my best and no one seemed to realise that Keino had performed brilliantly.”

Is cycling ready for its Kip Keino moment?

Tim Lewis’s book on Rwandan cycling, In The Land of Second Chances, is available now.