Notes:
Team Ossa works rider Conrado Cadirat, 28, suffered a fatal accident while competing in the 24 Horas Motociclistas de Montjuïc organized by the Peña Motorista Barcelona, held on Saturday, 04 and Sunday, 05 July 1959.

About five-and-a-half hours after the start of the race, in the early hours of Sunday morning Conrado Cadirat touched wheels with another competitor while running at a speed of 130 km/h along a straight of the street circuit. He was thrown from his motorcycle crashing head first against a kerb on the roadside. Cadirat who suffered a fracture of the base of his skull, facial injuries and a broken pelvis, was rushed to Barcelona hospital, where he died shortly after admission.

An experienced rider, Conrado Cadirat was a prominent figure on motorcycle rallies and regularity races in Spain, taking part occasionally in circuit events. He joined Eduardo Girò's team Ossa (Orfheo Sincronic S.A. founded in 1928) in the mid-1950, becoming a factory rider of the make, founded by Manuel Giró. From 1957 to 1959 Cadirat obtained a number of victories riding his Ossa 175S, including the Carrera del Barro, the Trofeo Pi y Solsona, the 1000 Km de Barcelona, the Rally Costa Brava and the Vuelta a Mallorca. Less than one year before his death, Conrado Cadirat's girlfriend was killed in a air crash near Madrid, a few days before their wedding.

Two works four-stroke Ossa 175S bikes were entered in the 5th edition of the 24 Horas Motociclistas de Montjuïc, the #8 of Walter Tassinari-Juan "Tey" Elizalde, and the #9 that Conrado Cadirat shared with Enrique Palero. Immediately after the accident that claimed the life of Cadirat, team Ossa withdrew the other machine from the event as a sign of mourning.

The race was marred by another accident, a female spectator was gravely injured being hit by a competitor while trying to cross the track just on his path. Winners of the race were Britain's Bruce Daniels-Peter Darvill on a BMW 600, who inherited the lead when Francesco Villa-Alfredo Balboni on a Ducati 175 had engine failure with less than one hour to the finish line.

• Book "40 Años de Historia del Automovilismo en el Circuito de Montjuïc", by Javier del Arco de Izco, Reial Automòbil Club de Catalunya, Spain, 2000, ISBN 84-931729-0-1, pages 127 and 557.
• Newspaper "Stadio" (Bologna, Italy), issue of Monday, 06 July 1959.
• Newspaper "La Stampa" (Turin, Italy) issue of Monday, 06 July 1959, page 4, article "Tragica fine a Barcellona del motociclista Cadirat", retrieved by website http://www.archiviolastampa.it/ .
• Newspaper "La Vanguardia" (Barcelona, Spain), issue of Friday, 10 July 1966, page 42, article "24 Horas Motociclistas de Monjuich".
• Website Racing Memory by Vincent Glon, page http://racingmemo.free.fr/M%20COURSES%20INTER/MOTO%2024%20BARCELONE.htm .
• Website Atlas F1, bulletin boards, "The Nostalgia Forum", thread "Speed's Ultimate Price: The Toll", page 39, posting by Hugo Boecker, message http://forums.autosport.com/index.php?showtopic=9705&view=findpost&p=1646425.
• Website Atlas F1, bulletin boards, "The Nostalgia Forum", thread "Speed's Ultimate Price: The Toll", page 43, posting by "jarama", message http://forums.autosport.com/index.php?showtopic=9705&view=findpost&p=1777168.
• Website Apuntes de las OSSA y la competición, page http://www.lamaneta.net/motoguapa/OSSAcompeticion.html .
• Website OSSA 1944-1983, page http://motoguapa.lamaneta.net/historia3.html .