Gilera 500-4 Racer

Gilera, like their Italian competitors MV Agusta, had aristocratic beginnings. In 1909 the Arcore company was founded by Count Giuseppe Gilera, rapidly making its mark as a producer of high-quality singles. But it was for high­ revving racing fours that the company is best remembered.

Between the start of the world championship in 1949, and 1957 when they pulled out of racing, Gilera won a remarkable 33 grands prix, three manufacturers’ championships and six world titles.

Specifications

Engine

Horsepower

transmission

Frame

Brakes

top Speed

Years in Production

air-cooled 499cc DOHC four

70 bhp @ 10500 rpm

5 or 7 speed

tubular steel twin cradle

double drum / drum

155 mph (over 165 mph with dustbin fairing

1949 – 1957

The basis for the success was Count Gilera’s 1936 acquisition of the Rondine four-cylinder engine, which was itself based on the 1926 OPRA push-rod design. The supercharged Rondine featured double overhead camshafts and liquid cooling. A year later a development of this engine brought Gilera a world speed record of 170mph at the hands of development engineer Piero Taruffi – a success a certain Mr Mussolini was not slow to exploit. In 1939 Dorino Serafini won the 500cc European championship on a similar machine.

Despite inferior handling, the post-war ban on supercharging theoretically favoured Gilera’s multi against the opposition singles and twins. Pietro Remor was responsible for redesigning the four into air-cooled, normally-aspirated form . In 1949, two grand prix wins brought Nella Pagani and Gilera second place in the inaugural championship. A year later Umberto Maserti went one better, but in 1951 the irrepressible Geoff Duke brought Norton’s 500 single their first title. Masetti won again in 1952, but for the following year Gilera covered all bases by recruiting Duke to ride the 500.

The Englishman took the title in each of the next three years. The 1956 crown went to another British legend, John Surtees, on another Italian four, the MV, before Libero Liberati brought Gilera their last title in 1957. In the same year, Bob McIntyre made history when his 500 Gilera became the first machine to lap the Isle of Man TT course at l 00mph.

Gilera returned to racing with much the same machinery in 1963 , under Duke’ s Scuderia Duke banner. The venture lasted only one season, but it was a measure of the bike ‘s prowess that John Hartle, Phil Read and Derek Minter brought the six year-old hardware to second place in the manufacturers’ championship.

Part of the machine’s continued competitiveness lay in its aerodynamics. Although the same Pietro Remor was responsible for both engines, the Gilera enjoyed a considerably more compact engine than the MV four, with more efficient and stable streamlining. The Gilera is a mere 15½ inches wide at the crankcases·, which split horizontally and contain a built-up, roller bearing crankshaft running on six main bearings. T he lower left frame rail demounts for engine removal , again permitting a more compact overall design . Each of the cylinder barrels is a separate casting. Its twin overhead camshafts were driven by a central train of gears from the crankshaft.

Gilera 500 4

Although this was a long-stroke design, less revvy and more driveable than later MV and Benelli fours, its four small cylinders allowed a compression ratio of 11:1 and maximum revs around 11,000 per minute. Four 28mm carbs were employed, with four crackling megaphone exhausts at the rear. The Gilera pictured is a 1957 five-speed machine, although an experimental seven-speeder later followed.

Gilera was taken over by Piaggio in 1970, concentrating on small capacity commuter and off­road machines. T he early ’90s saw an abortive return to 250cc grand prix racing. T hen, in 1994, the parent company allowed this once great name to die in the name of ‘rationalisation’. Although nowadays, scooters produced by Piaggio are also sold under the Gilera brand.

As the first of the post-war fours to achieve racing success, the Gilera enjoys a special place in racing history. It would be the Japanese who first put a comparable machine into large scale production, and today the transverse four is by far the most common high-performance format.

But it was those fiery Italians who first showed the way.

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