Pirelli’s naming structure is a little confusing, but the new Diablo Rosso IV Corsa is the sportiest in the Diablo Rosso line.
Begin press release:

Pirelli presents the new DIABLO ROSSO IV Corsa, the high-performance hypersport tire that raises the bar of sport riding even higher within the DIABLO ROSSO family. The new DIABLO ROSSO IV Corsa represents a fiercer version of the DIABLO ROSSO IV supersport tire, created to satisfy the most demanding motorcyclists seeking a tire capable of high performance, to fully utilize the potential of their bikes.
DIABLO ROSSO IV Corsa was born in the year in which Pirelli celebrates its 150th anniversary and becomes an integral part of the celebrations. During 2022 a limited edition DIABLO ROSSO IV Corsa pays homage to this milestone and features the Pirelli’s 150th anniversary logo on its sidewall. DIABLO ROSSO IV Corsa with Pirelli 150th anniversary logo.
Formed in Milan on January 28, 1872, the company began its business with diversified rubber products, making the first tire for bicycles in 1890. Always passionate about competition, Pirelli participated in the first motorcycle races in 1897 and today continues with the role of sole supplier to the Superbike World Championship, a collaboration that started in 2004, as well as being the most successful brand in MXGP. Today Pirelli is the only tire company focused exclusively on the consumer world, with products and services for cars, motorcycles and bicycles.
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