SUNDAY, APRIL 7, 1968. Hockenheim never was a circuit for the fainthearted. Its fast straights negated pure driving skill, turning races into balls-out slipstreaming epics in the days before chicanes were finally introduced to slow things down.

Jim Clark did not want to be there. He was supposed to be driving the new Ford F3L sports prototype at Brands Hatch for Alan Mann Racing. But by the time Mann asked Clark, the Scot had already given his word to Team Lotus chief Colin Chapman, the friend with whom he had risen to the top, that he would race his Lotus 48 at Hockenheim.

Clark, 32 and world champion three years earlier, had been struggling all weekend with misfires and his Firestone tyres, which hated the cold, damp conditions. Englishman Derek Bell, a coming man, remembered being stunned over breakfast on race day when Clark said to him: “Don’t get too close behind me when you come up to lap me, because my car is cutting out intermittently . . .”

“If Stirling Moss was my hero, Jim Clark was my idol,” Bell recalled. “This was my idol saying, ‘When you come up to lap me . . . ’ It wasn’t easy to take in.”

Clark’s mechanic, Dave “Beaky” Sims, had spent the early hours of the morning running the Lotus up and down the road trying to cure the misfire. “The problem was, it was freezing. It was so cold it was affecting the fuel metering units. The drive belts were breaking. In the end I used boiling water. That cured it.” Sims would be the last man to talk to Clark, and said: “He told me he wasn’t happy with the handling in the wet. He told me not to expect too much. He wasn’t confident, but I don’t think he feared anything was going to happen to him.”

Max Mosley, now president of the FIA, but then a rookie F2 racer, was also driving. “The first corner was thick spray,” he remembered. “I was thinking, ‘this isn’t a good idea’. All you could do was steer by looking at the tops of the trees, because you couldn’t see where the track went. I backed off, expecting everyone to pass. To my astonishment they didn’t.”

Clark was eighth when he came round the stadium at the end of the fourth lap. He failed to appear next time around. The red, white and gold Lotus had spun at 160mph on a gradual curve shortly after the first corner and crashed into the forest’s unyielding trees, and in as much time as it takes to read these words, the world’s greatest driver was killed.

There were inevitably theories about the cause of the accident. Children had run across the road, causing him to swerve. The misfiring engine had cut out, causing the loss of control. Sims had no doubt. “It was a right-rear tyre deflation,” he said. Bell was not so sure, and has often wondered about that engine misfire. “Beaky has always said it was down to the tyres. I once said to him, ‘What about the engine cutting out?’ and he confirmed it was doing it all weekend. He’d told Jimmy he couldn’t fix it. I could see it: he goes through that curve, the engine cuts out, the thing gets itself sideways as a result, the engine suddenly cuts back in when he’s out of shape . . . who knows?”

An official report suggested the Firestone tyre had picked up a puncture and suffered an explosive decompression, pulling its beads off the wheel rim, throwing the Lotus beyond the control even of a driver of Clark’s stature. “I was shocked,” Mosley remembered. “It was like Ayrton Senna, except in those days such things were more usual. But Jim Clark was the one nobody ever expected it would happen to.” Graham Hill was stunned. Later, he would tell Clark’s girlfriend, Sally Stokes, when asked what he would miss most about his fallen comrade: “I’ll miss his smile.”

Clark was part of the fabric of his sport, a sheep farmer from Scotland who became a shy champion, dominating the mid1960s in his Lotus long before the world had heard of Senna and Michael Schumacher. His performances passed into a legend woven around a record 25 grand prix successes from only 72 starts, capped by countless other victories in all manner of machinery; two world championships and at least another two lost to ill-fortune; and a singular triumph in the Indianapolis 500.

At the wheel, Clark was in total control. Yet when he stepped from the cockpit he reverted to his innate shyness. The spotlight left him feeling uncomfortable, and he often wondered what all the fuss was about.

In 1962, in South Africa, his first world championship had slipped away because of mechanical failure in the final race. Two years later, in Mexico, the same thing happened to him, within sight of the chequered flag. Both times he accepted fate’s blows with dignity. That was how Clark was, and why he was as revered as Fangio and Moss had been before him. Clark was an intensely private man. When he went to America to compete, he detested the national penchant for overfamiliarity. “I hate it,” he said, “when people keep saying, ‘Hi Jimmy!’ to me. They don’t know me!”

This was a man who possessed characteristics with which ordinary people could identify: humility, loyalty, a lack of self-confidence, occasional testiness with the foolish or boorish. Out of the cockpit he was disorganised and indecisive. Four decades after his death, Clark remains a yardstick not only for outright performance, as he was in his heyday, but also by which to judge the behaviour of other champions both on and off the track. He would have been appalled when Senna deliberately swerved at Alain Prost down the main straight at Estoril in 1988, or when he turfed his French rival out of the race in Suzuka two years later. He would have hated Schumacher’s treatment of rivals Damon Hill and Jacques Villeneuve. To Clark, the manner in which the game was played was as important as the outcome.

At the funeral, Clark’s father told Dan Gurney he was the only rival his son truly feared. “It destroyed me, really, in terms of my self-control,” Gurney admitted. “I was drowned in tears. To hear that from someone whose son had been killed, and wasn’t there any more, it was more than I could cope with.”

Jackie Stewart, Clark’s close friend, would inherit his mantle. “Jimmy’s death was to motor racing what the atomic bomb had been to the world,” he said. “Jim Clark was everything that I aspired to be, as a racing driver and as a man.”

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