Giuseppe Gilera, born in 1887, founded his company aged 22. His first model used a 317 cc single-cylinder overhead-valve engine producing 7 hp, weighed 75 kg, and reached 105 km/h. After the First World War, the factory relocated to Arcore, between Milan and Lecco — close to the Monza racing circuit. Racing was embedded in the company's culture from the start, with Giuseppe's brother Luigi a successful ISDT competitor in the early 1930s.
The pivotal moment in Gilera's racing history came in 1935, when the company acquired rights to the CNA Rondine, a supercharged water-cooled four-cylinder machine producing around 80 hp at 9,000 rpm and capable of 230 km/h. This extraordinary engine formed the basis for Gilera's racing machines for nearly four decades. From the mid-1930s, Gilera developed a range of four-stroke competition engines spanning 100 to 500 cc, including the celebrated 1939 Saturno, a 500 cc single designed by Giuseppe Salmaggi and inspired by the pre-war VTEGS.
After World War II, Gilera's four-cylinder 500 cc machines dominated Grand Prix racing. The marque won the 500 cc world championship in 1950, 1952, 1953, 1954, 1955, and 1957 — six titles in eight seasons. Geoff Duke, one of the era's most celebrated riders, was among those who achieved much of their success on Gilera machinery. The four-cylinder engine also proved competitive in sidecar racing, delivering eight victories in that class between 1949 and 1952 for riders including Ercole Frigerio and Albino Milani.
Facing escalating costs and declining motorcycle sales in a market increasingly dominated by automobiles, Gilera entered a gentleman's agreement with the other major Italian manufacturers — MV Agusta, Moto Guzzi, and Mondial — to withdraw from Grand Prix racing after the 1957 season. The factory machines were mothballed.
In 1963, Geoff Duke arranged for the 1957 500 cc machines to be resurrected, challenging the dominance of Mike Hailwood on MV Agusta. Running on improved 1960s tyres, the old Gileras were considered competitive. Derek Minter and John Hartle raced them at Silverstone, Brands Hatch, and Imola with early success. Phil Read joined the team for the TT, finishing third to Hartle's second. The campaign ran for one season only. In 1966 Minter again attempted to race the Gileras at the TT, without success after crashing in practice.
The four-cylinder Gilera engine continued to appear in niche applications through the early 1960s. In 1954 Piero Taruffi used it in the record-breaking TARF streamliner, and Swiss privateer Florian Camathias won a sidecar race with a Gilera four-cylinder engine as late as 1964.
After withdrawing from competition in 1957, Gilera shifted direction: the brand downplayed its successful four-stroke singles and attempted to redirect towards motocross and off-road competition through a partnership with independent specialist Elmeca. Sales declined through the 1960s and by 1968 the company was in receivership. In 1969, Gilera became part of the Piaggio group.
In 1992, Gilera made a return to the Grand Prix arena under Piaggio ownership. The historic factory at Arcore was closed in 1993, and from then on the Gilera name was applied exclusively to small-displacement scooters manufactured by Piaggio at its Pontedera facility.
Gilera's pre-war acquisition of the Rondine and the subsequent development of the four-cylinder racing engine stands as one of the defining engineering decisions in motorcycle racing history. The architecture that Gilera refined in the 1940s and 1950s directly influenced the design of MV Agusta's championship-winning machines after MV hired away Gilera's key engineer Piero Remor and mechanic Arturo Magni in 1949. The six 500 cc world championships Gilera won between 1950 and 1957 represent one of the most concentrated records of success in the sport's history.