Pasolini was born in Rimini, in the Romagna region of Italy — the heartland of Italian motorcycle racing tradition. His father was a motorcyclist and introduced him to both motocross and road racing from a very young age. A smoker and self-described party-goer, Pasolini was an unconventional athlete: he brought a combination of balance and controlled aggression to his riding that set him apart visually from his contemporaries.
He began his motocross career in 1958, having previously shown interest in boxing and football. His transition from motocross to road racing came in 1962, when he debuted on an Aermacchi 175cc machine. His first two finishes ahead of a young Giacomo Agostini sparked what would become one of the defining rivalries of Italian motorcycle racing in the late 1960s. Pasolini then took a two-year break to complete compulsory military service, during which time he was stationed in Sardinia and met his future wife Anna; together they had two children, Sabrina and Renzo Stefano.
Pasolini resumed racing in 1964 on Aermacchi 250cc and 350cc machinery. By 1965 he was contesting the Italian championship on a Benelli, finishing second in the 250cc class to Tarquinio Provini and third in the 350cc class behind Agostini and Giuseppe Mandorlini. The 1966 season included one particularly notable result: victory in the final race of the Italian championship on the then-new four-cylinder Benelli 500.
With increasingly competitive equipment, Pasolini entered epic confrontations with Mike Hailwood on Honda machinery and continued his long-running battle with Agostini on MV Agusta. The 1968 season saw him finish second to Agostini in the 350cc championship after claiming both the 250cc and 350cc Italian titles.
He raced throughout this period with a distinctive visual signature: an open-face helmet and black horn-rimmed glasses, at a time when the majority of competitors had already adopted full-face helmets. The image made him immediately recognisable and contributed to the cult of personality that surrounded him.
In 1969 Pasolini narrowly lost the 250cc world championship to Benelli teammate Kel Carruthers. The following season new regulations limited the 250cc class to twin-cylinder machines, prompting Benelli to redirect resources toward the 350cc category. After an underwhelming season Pasolini left Benelli for Aermacchi, by then operating as Aermacchi/Harley-Davidson following a corporate merger. Much of the 1971 season was consumed by development testing on the new 250cc machine, which proved slower to mature than anticipated.
The 1972 250cc world championship delivered Pasolini's closest approach to a title. Racing against Jarno Saarinen — a Finnish rider who was reshaping the sport — Pasolini lost the championship by a single point. He finished the year with five Grand Prix victories to his name and a reputation as one of the most dangerous threats in the 250cc and 350cc classes.
On 20 May 1973, at the Italian Grand Prix at Autodromo Nazionale di Monza, Pasolini was unable to finish the 350cc race due to a mechanical problem. Retiring with four laps remaining, he subsequently lined up for the 250cc race. On the opening lap he fell, and Saarinen — immediately behind him — could not avoid the stricken motorcycle. The crash triggered a chain reaction involving twelve riders in total and claimed both Pasolini's life and Saarinen's.
The probable cause has been debated ever since. The most widely accepted explanation is that oil spilled by Walter Villa's Benelli during the 350cc race — the rider having continued despite the leak to score championship points — remained on the track surface when the 250cc race began. Race officials failed to order the track cleaned between events. One rider, John Dodds, raised his concerns with authorities before the race and was reportedly threatened in response. The damage to Pasolini's motorcycle was also consistent with an engine seizure, leaving the exact triggering event unresolved. He was buried in the Monumental Cemetery of Rimini; his helmet and racing memorabilia are displayed at his tomb.
Renzo Pasolini's name was memorialised in 1985 when Ducati unveiled the Ducati Paso 750 at the EICMA motorcycle show — a landmark sports motorcycle designed by Massimo Tamburini and named directly in Pasolini's honour. The name acknowledged both Pasolini's association with Italian motorcycle culture and the widespread affection in which he was held by the industry and racing public alike.