This first-generation Porcupine will remain in the history books forever.

The 500-cc parallel-twin AJS E90 Porcupine is the rarest and most exotic factory road racer ever entered by a British factory in Grand Prix racing — and also, in some ways, the most frustrating. Yet its position in history is assured, as the first-ever winner of the premier class 500 cc World Championship (which later mutated into MotoGP) exactly 75 years ago this year, with British rider Les Graham winning the world title aboard the AJS in 1949. Indeed, the AJS is still the only twin-cylinder bike ever to have won the 500 GP world title — singles did it later, and triples and fours too, of course, but never another twin. The AJS Porcupine was both first and last.

That six-race 1949 World Championship series had started badly for the AJS works team, when Graham led the Senior TT for almost the entire race before breaking down on the run to the flag with a broken magneto drive, and pushing in from Hilberry to finish tenth. The Isle of Man was not a happy place for Porcupine riders, who only once (in 1951) in the bike’s eight-year racing career ever succeeded in even finishing on the podium there.

Enough Points for the Win

But Les Graham took victory in the Swiss GP on Berne’s gruelling and slippery cobblestoned Bremgarten circuit, to record the AJS twin’s first Grand Prix win. He repeated this success in the Ulster GP later that year, with his 96.49 mph (155.3 km/h) average speed and new lap record of 98.08 mph (157.9 km/h) making the Northern Irish Clady circuit the fastest in the world at that time.

Meanwhile, Graham had finished second to Pagani’s Gilera four at Assen, before retiring with a split fuel tank at Spa, in a Belgian GP won by his teammate Bill Doran.

Even before the end-of-season Italian GP at Monza, in which Doran finished third. Graham retired after being hit from behind by Pagani’s Gilera teammate Carlo Bandirola. With only a rider’s best three results counting in the final points table, Graham had done enough to win the inaugural 500 cc world title for the British marque, with AJS also winning the manufacturers’ crown.

Inspiring A Legend

Eleven-time British Trials Champion and twice European Trials Champion, as well as a multiple road racing GP podium finisher, Sammy Miller’s passion for motorcycles was born as a boy growing up in Northern Ireland in the post-Second World War era — and it was the AJS Porcupine that fired this.

“My first impressions of anything to do with bike racing came when some of my pals and I rode our bicycles up to the Clady circuit on the Thursday evening, for the first night of practice for the Ulster GP,” recalls Sammy, today an energetic and enthusiastic 90 years young. “There we were in the…