Americans loved Evel Knievel. They loved his ruggedness—a wild boy from Butte, Montana, grown into a swashbuckling superstar, King of the Daredevils, somewhere between Buffalo Bill and the Greatest Show on Earth. They loved to watch him fly. And even as it made them wince, they loved to watch him crash.

But most struggled to understand why anyone would willingly put themselves through that torture, limping from hospital to motorbike and back again, over a 15-year jumping career that busted almost every bone in his body.

In fact, there were two reasons: First, he loved it, famously remarking that life was otherwise boring. Later, beleaguered with tax and bank debts, he was financially unable to stop. Knievel was a salesman as much as he was a showman, and his go-for-broke, larger-than-life, jumpsuit-wearing persona was what he had to sell. “I created the character called Evel Knievel,” he told the St Petersburg Times in 1998, “and he sort of got away from me.”

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Born Robert Craig Knievel, he was raised by his grandparents in Butte. It was a rough copper-mining town, scarcely developed from its frontier days of street-fighting, prostitution, gambling and public drunkenness. Knievel was in his element. As a teenager there, he was a talented athlete. In his early adulthood, he variously worked in the mines; made 30 jumps as an army paratrooper; played semi-professional and professional hockey; and rode and raced rodeo horses, stock cars and motorcycles.

At 13, he stole his first motorbike, a Harley-Davidson. Three years later, his grandmother replaced it with a Triumph. He had a particular hobby of throwing stones at sex workers—the game was to outrun their irascible pimps. Knievel’s nickname, in fact, came from another brush with criminality. He had been arrested for stealing hubcaps and placed in a cell next to one “Awful Knofel.” The police, inspired, dubbed him Evil Knievel. The name stuck so fast that Knievel eventually made it his legal name—written with an “e” rather than an “i.”

Throughout all of these starts and stalls, it was motorcycles that he loved most of all. At six feet tall, however, he was uncompetitive as a racer, and instead opened his own dealership in Butte. But even his natural salesmanship was no match for a town of people living largely paycheck to paycheck. In 1963, it failed. Next, Knievel and his young family moved to Spokane, Washington, where he flourished in a series of jobs with Honda dealerships, offering a $100 discount to anyone who could beat him in an arm-wrestle. (No one, he would later recount, received that discount.)

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American bikers had little interest in Hondas, often writing them off as shoddy Asian-made imports. Making his fortune selling them, Knievel realized, might require a little ingenuity. And so he started to think more ambitiously about the kind of stunts that might prove the bikes’ worth—and reel in customers, to boot.

By the mid-1960s, he was an extremely capable motorcyclist, with fond memories of his childhood hero, the stunt racecar driver Joie Chitwood, impresario of a popular auto thrill show that traveled around North America. In 1965, Knievel forged a plan. He would launch himself on the back of a Honda 40 feet over two borrowed mountain lions and a cage of rattlesnakes. The performance may have lacked some of the glitz of his later jumps (no spangled jumpsuit, for instance), but it wasn’t short on excitement. As he later recalled: “I jumped 50 rattlesnakes in a 90-foot box and two mountain lions, but smashed into the edge of the box. All the snakes got out and the people had to run down the mountain.”

Knievel’s stunt didn’t do much to sell bikes. But it did leave him wondering whether there might be a niche in the market for Chitwood-style stunt racing—on two wheels instead of four. The following year, the newly christened show “Evel Knievel and his Motorcycle Daredevils” made its first public appearance. In the process, he had invented not just a whole new sport, but a career that would make him famous—and, for a time, very wealthy.

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Between 1965 and 1980, Knievel performed dozens of these stunts all over the world. In 1972, for instance, he and his Harley Davidson XR-750 flew over 100 rattlesnakes and 2 vans. Three years later, he successfully cleared 14 Greyhound buses in Mason, Ohio. The vast majority of his jumps were successful, though he is often better remembered for the ones that didn’t quite work out.

Among the most infamous jumps: a 1967 New Year’s Eve performance where Knievel attempted to ride his motorcycle across the Caesars Palace fountain in Las Vegas, Nevada. As he hit the ground, his body bounced against it like a rag doll, causing multiple fractures and a concussion. He spent nearly a month in a coma. The footage of this botched jump was shown almost everywhere, and Knievel became a household name.

Over the next six years, he jumped Mack trucks and piled cars, Cadillacs and Chevrolets. In 1974, he attempted a jump still more death-defying. After failing to receive governmental approval to clear the Grand Canyon, he mounted a steam-powered rocket, the Skycycle X-2, and attempted to careen over Idaho’s Snake River Canyon. But his parachute deployed too early, and he was blown back onto the rocks in an anti-climatic finish.

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In May 1975, Knievel announced his retirement. In London’s Wembley Stadium, some 70,000 people gathered, mouths agape, as he attempted a 100-mph jump over 13 buses. He had been hitherto unknown in Great Britain, but his flamboyant ways—the flashy speech, the diamond-studded cane with the hidden liquor compartment, the Cadillac pickup truck—made him a favorite with the press. The jump failed. He miscalculated the distance and speed, and crash-landed on the final bus. He limped over to the microphone and announced: “I will never, ever, ever jump again. I’m through.”

Not exactly.

A few weeks later, Knievel announced his plans to return to London and tackle those buses all over again. “You told 70,000 people you were going to retire,” a reporter at John F. Kennedy Airport said. “How can you say now that you’re going back?” “I don’t care what I say,” Knievel called from the gurney. “The schedule calls for me to jump again in September.”

He didn’t ever go back to London—but he did continue to jump for another five years. It’s likely he would have stopped much earlier, had it not been for the demands of the IRS. Knievel had, he said, “made about $50 million and spent about $55 million” during his 15-year stunting career, most of which he had failed to pay tax on. Well into the 1980s, he was heavily in debt, and to pay it off, he took to selling his planes and the rights to the Evel-branded toys that had once been in the house of almost every American schoolboy.

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Yet despite the scrapes and fractures, Knievel loved what he did. In a 2007 interview with Maxim, shortly before he died of chronic lung disease, he told the magazine that he had stopped only because he was tired of “getting beat to death.” Why he did it in the first place, he said, should have been apparent: “I wanted to fly through the air. I was a dare­devil, a performer. I loved the thrill, the money, the whole macho thing. All those things made me Evel Knievel.”