Giuseppe Gilera began building motorcycles at Arcore near Milan in 1909, and the firm became one of Italy's longest-lived manufacturers. In the 1930s the supercharged Rondine four set world speed records, and after the war the Gilera 500 four won multiple 500 cc world championships with riders including Umberto Masetti and Geoff Duke.

The road range was more conventional but durable, from the Saturno single to light commuters and mopeds produced in large numbers. Piaggio acquired Gilera in 1969, and the name later appeared on sporty scooters such as the Runner, DNA, Nexus and the large GP800 twin, keeping the marque in production well into the modern era.

Gilera manuals cover four-stroke and two-stroke engine service, carburetor and fuel-injection tuning, clutch and gearbox work, suspension and brake service, and complete electrical diagrams. Classic documentation includes magneto timing and bearing clearances for vintage engines, while scooter-era books add CVT and liquid-cooling procedures, and frame and fork service follows period practice.

Restorers working on a race-bred four-cylinder or a Saturno single, riders maintaining modern Gilera-badged scooters and independent garages all benefit from factory-accurate procedures. These engines reward correct settings and punish approximation, so documentation is a genuine tool rather than a formality, and clubs and specialists keep examples running worldwide. A single manual often covers several model years, which suits scooters that changed gradually.