The warning was written in 1960 by the most respected man in British motorcycling. Edward Turner had crossed the world to tour the factories of Yamaha, Suzuki, and a Japanese company most British riders had barely heard of, run by a former mechanic named Soichiro Honda. He came home to the BSA group in Birmingham and set down what he had seen in a report he called a dynamic experience and a somewhat frightening spectacle. Japan, he recorded, already built more motorcycles than any nation on Earth, more than half a million a year against Britain’s 140,000.

Honda alone was approaching a quarter of a million annually. Turner saw the research effort, four hundred technicians at Honda on new designs. He saw banks of single-purpose automatic machine tools turning out in a single day what a British works took a week to make. And then he reached the conclusion that mattered, the one the whole company would die by.

The Japanese, he judged, would stay in the small commuter machines. The big, traditional motorcycle, the proper half-liter and upward, would remain British. He was the man who had made the British motorcycle what it was. Born in Camberwell in 1901, the son of a small engineering manufacturer, Turner had gone to sea with the merchant navy and come back with an instinctive feel for machinery and an unshakeable confidence in his own judgment.

In the late 1920s he carried that confidence north to Birmingham, where Jack Sangster, who ran the Ariel marque, took him into the drawing office. There Turner produced the Ariel Square Four, a compact four-cylinder machine that made other engineers stop and look. In 1936 Sangster bought the motorcycle side of Triumph, a Coventry firm with a famous name and a balance sheet that had nearly carried it into oblivion, and installed Turner, not yet thirty-five, as chief designer and general manager. Turner looked at the heavy single-cylinder bikes that dominated the market, dependable, sturdy, slow, and saw them as yesterday’s machines.

He reached for an idea others had tried and abandoned, the parallel twin, and refined it into something smooth enough to ride all day and fast enough to set the pulse racing. In the autumn of 1937 he gave it a name that promised precisely what it delivered, the Speed Twin. It weighed a little over 360 pounds, produced 27 brake horsepower, and would run beyond 90 miles an hour. Within a few years every serious British manufacturer was building a parallel twin cut to the Turner pattern.

On the night of 14 November 1940 the German Luftwaffe came for Coventry. By morning the cathedral was a roofless shell and the Triumph works on Priory Street was a blackened skeleton. Turner and Sangster did not fold. They found temporary premises in a former foundry in Warwick, kept the skilled workforce together, and within two years raised a new purpose-built factory on a green field beside the Warwickshire village of Meriden, which claimed to be the traditional center of England.

The war that had nearly killed Triumph also set the industry up for the boom to come. Three miles away stood BSA, the Birmingham Small Arms Company, founded in 1861 by fourteen gunsmiths. During the war it made rifles, machine guns, cannon, and above all the BSA M20 motorcycle, more than 126,000 of them, the standard dispatch rider’s machine of the British army, carried across the deserts of North Africa. The Small Heath factory was bombed, with more than fifty workers killed on one terrible night.

Production never stopped. When peace came in 1945, the government’s message to industry was painted on every factory wall in the land. Export or die. And the answer lay three thousand miles west.

The customers were in America. A generation of young Americans came home with money, a taste for speed, and a restlessness the wide empty roads seemed built to answer. The American industry had collapsed into a single maker of big heavy leisurely machines. Into that gap rode the British, light, quick, glamorous, unlike anything built on American soil.

Turner crossed the Atlantic himself, walked the dealerships, and grasped a single staggering fact. There were more potential motorcycle buyers in California alone than in the whole of the United Kingdom. He built for them. In Pasadena, a former cycle dealer named Bill Johnson had built the Triumph franchise into Johnson Motors, JoMo to everyone in the trade.

On the East Coast, the Triumph Corporation in Baltimore was run by an expatriate engineer named Dennis McCormack. Between them they sold more Triumphs than the factory could comfortably build. The machine that sealed it arrived in 1949, the 650 Thunderbird, conceived expressly for the American buyer. Turner, the showman, knew it needed a legend.

That September he took three new Thunderbirds to the great banked bowl at Montlhéry outside Paris. Each was ridden 500 miles at an average above 90 miles an hour, and each then rode home to Coventry under its own power. The Thunderbird became a sensation. By the opening of the 1950s, more Triumphs were sold in the United States than in Britain.

In 1951 BSA bought Triumph, and Turner rose to command the combined group. At its height in the 1950s, roughly one in every four motorcycles sold anywhere on the planet wore the BSA badge, and Small Heath was the largest motorcycle factory on Earth. In America, the British motorcycle had become cool, largely by accident, through the cinema. In 1953 Marlon Brando appeared in The Wild One, and the machine he rode, slouched over the bars, was his own personal Triumph Thunderbird.

The image went round the world. The British censors banned the film outright, and it was not shown openly in Triumph’s own country for fourteen years. James Dean was photographed astride his Triumph in a black leather jacket, then dead at twenty-four. And then came Steve McQueen, the coolest man in Hollywood and no poser but a genuine competition rider who collected Triumphs and raced them across the California desert.

In the 1963 film The Great Escape, the great leap for the wire was performed on a Triumph TR6 disguised with military paint, ridden by McQueen’s friend and stunt double Bud Ekins. The Bonneville, named for the Utah salt flats where a Texan named Johnny Allen had taken a Triumph-powered streamliner beyond 214 miles an hour in 1956, became the most desirable motorcycle in the world. In the spring of 1964 McQueen came to Meriden as a member of the American team for the International Six Days Trial, walked the factory floor, and met the men. This was the summit, and the view from the top seemed clear in every direction.

By the time McQueen walked that floor, the warning had already been written and quietly set aside. Turner had stepped back from the front line, easing out of his commanding role through the middle of the decade. He died in August 1973, just as the company he had built was sliding into its final crisis. The report he had sent home from Tokyo had been read, circulated, noted, and filed.

Turner had concluded that the Japanese would never learn to build a machine a Brando or a McQueen would want to be seen on. While he was wrong about that, the rest of what he saw was growing more monstrous with every year. A later government study set down the figures in cold print. At Honda’s Suzuka factory roughly 350 machines were built per man per year.

At the British works at Wolverhampton, 18. At Small Heath, the largest motorcycle factory on Earth, 10. Behind the figures stood Honda’s advertising, You meet the nicest people on a Honda, which peeled the motorcycle away from the leather jacket and the menace of the Wild One and handed it to the clerk, the student, the ordinary family. By the mid-1960s Honda commanded more than half the American market, selling to people the British had never thought to sell to.

There was a way out, and the British industry had drawn it and prototyped it and could not bring itself to build it. As early as 1963, Bert Hopwood, Turner’s old protégé and now one of the finest engineers in the country, had a plan with the development engineer Doug Healey. They would take the Triumph twin and add a third cylinder, a 750 triple. By 1965 they had a prototype running.

Management dithered for three years. When the triple finally reached the market in September 1968 as the Triumph Trident and the BSA Rocket 3, it came with its price set too high, its styling handed to an outside design house with results that divided opinion violently, and a delay of the better part of a year and a half. It reached American showrooms just ahead of the Honda CB750, which arrived in the closing months of 1968. For a few weeks the way out was actually on sale.

Then the Honda landed. Four cylinders across the frame where the British built two, an overhead camshaft where they used push rods, an electric starter, a hydraulic disc brake, five gears, 67 brake horsepower, a genuine 125 miles an hour, and it did not leak oil. In the United States, the market on which Triumph’s whole existence depended, the CB750 carried a sticker of $1,495. The British triple cost the thick end of $2,000.

Dealers in California began canceling their orders for the Rocket 3. The warning came up the chain from the men with the order books in their hands, and it changed nothing. In 1971 the BSA group bet the company on a relaunch, a new range of thirteen models built around an oil-bearing frame. The execution was a catastrophe.

The new frame raised the seat of the Bonneville to around 34 inches, too tall for many riders to sit on with both feet flat on the ground. The bikes were late, desperately late, and chaotic when they came. The tooling was not ready. The parts did not fit.

The 1971 range missed the American spring selling season entirely, and thousands of machines ended up stranded in American warehouses, to be dumped later at heavy discount. The BSA group posted a trading loss of eight and a half million pounds. The independent BSA group was finished. The government stepped in, putting up nearly five million pounds of public money to fold the ruined BSA and Triumph business together with Norton Villiers.

The new combine, Norton Villiers Triumph, was headed by Dennis Poore, a former racing driver and wealthy English patriot. Poore looked at his four factories, Small Heath, Andover, Wolverhampton, and Meriden, and decided to close Meriden, the most modern plant and the home of the most famous product in the range. On 14 September 1973 he came to Meriden, told the assembled management the plant would shut with the loss of all 1,750 jobs, declined to take questions, and left. The men on the factory floor read it on the billboard of the midday Coventry Telegraph.

Triumph Meriden to close. They shut the gates themselves and chained them. What began that afternoon lasted eighteen months. At first it was a work-in, and then, at a mass meeting at the start of October, the men voted to blockade the works altogether.

Around eighty men at a time picketed the gates in shifts, around the clock, through the autumn and into the winter of the three-day week, when the whole country’s power was rationed and the lights went out. They were not striking for higher wages. They were fighting for the right to keep doing the work their fathers had done. Into that standoff walked Tony Benn, Secretary of State for Industry in the new Labour government, who saw in the chained gates a chance to prove that workers could own and run their own factory.

His civil servants advised him in plain terms that a cooperative at Meriden was not commercially viable. He backed it anyway. In July 1974 the government put up just under five million pounds. The men formed Meriden Motorcycles Limited, adopted a single flat wage for every man from the floor to the top, and in March 1975, eighteen months after Poore had walked out of the gate, the line at Meriden started up under the ownership of the men who worked it.

It outlived the company that had tried to close it. The men kept building the Bonneville year after year into the 1980s. What killed them in the end was the pound. In the early 1980s the pound soared on North Sea oil to nearly two and a half dollars, and the Meriden Bonneville, which lived and died on the American market, was priced out of existence.

In August 1983 the cooperative closed. The factory was pulled down in 1984. The housing estate built on the ground has streets named Bonneville Close and Daytona Drive. In 1983 the Triumph name was bought by a Midlands property developer named John Bloor, who wanted to build motorcycles.

At a new factory at Hinckley in Leicestershire, an all-new company relaunched the Triumph name in 1990 and sells fine motorcycles around the world. It is a worthy heir, not a resurrection. The line that ran unbroken from the Speed Twin through Meriden was cut. They were warned in writing in 1960.

They were warned by their own engineers, who drew the machine that might have saved them. They were warned a third time by the men in California with the order books in their hands. The British motorcycle did not fall to one Japanese motorcycle, however brilliant. It fell to twenty years of reasonable-seeming decisions, each one easier than the alternative, made by men who could not quite imagine that the warmth they were standing in would ever fade.

The Honda was only the messenger. And the largest, proudest, most glamorous motorcycle industry the world had ever seen became, in a little over a decade, a demolished factory under a quiet housing estate in the village that once called itself the center of England.