OTK Kart Group S.r.l., also known as Original Tony Kart (OTK), is a go-kart manufacturer based in Prevalle, Lombardy, Italy. Founded in 1958, OTK has won 35 CIK-FIA World Championships between 1986 and 2023 with its Tony Kart, Vortex, FA Kart, Kosmic, and Exprit brands.

With 35 titles, OTK is the second-most successful chassis manufacturer in the history of the World Championship, behind CRG. Across its -year existence, OTK has also won 14 CIK-FIA World Cups, three CIK-FIA International Super Cups, and 44 CIK-FIA European Championships. Notable World Champions on OTK machinery include multiple-time winners Davide Forè and Marco Ardigò, as well as Formula One drivers Jarno Trulli, Lando Norris, and Logan Sargeant.

History Tony Kart S.n.c. was founded in 1958 by Antonio "Tony" Bosio (23 February 1923 – 12 June 2015) in Prevalle, Lombardy, Italy. Bosio's craftsmanship was admired by drivers, who frequently visited his workshop. In 1965, Bosio built a special Tony Kart based on other land speed record designs with a 100 cc Parilla engine; at Monza, driver Livio Bolis set a record speed for a go-kart of . Bosio also collaborated with the Italian Winter Sports Federation (FISI) on the construction of bobsleighs. His work was credited with several innovations in kart design, such as the "floating" brake caliper.

Tony Kart chassis were originally painted Savoy blue before switching to Tony Kart Green in 1983, following the purchase of the company by Roberto Robazzi and Carlo Cancarini. Powered by a Pavesi engine, Fabrizio Giovanardi took Tony Kart's first CIK-FIA World Championship three years later, winning the Formula C (FC) gearbox class. Under control of the Robazzi family, Tony Kart continued to dominate throughout the "Golden Era" of the 1980s and 1990s, establishing itself as the second-most successful chassis brand in World Championship history behind CRG. Several Formula One prodigies featured in Tony Kart machinery throughout this period, including Michael Schumacher, Ralf Schumacher, Jarno Trulli, Sebastian Vettel, and Lucas di Grassi.

OTK expanded beyond the Tony Kart brand in the mid-1990s. In 1995, it founded Vortex Engines, evolving Tony Kart into a factory team. The following year, it established the Kosmic Kart brand and, throughout the 2000s, established Redspeed Kart and Exprit Kart, as well as the Trulli—the first collaborative chassis with a Formula One driver. From 2009 to 2020, OTK partnered with two-time Formula One World Drivers' Champion Fernando Alonso on the FA Kart chassis. It later established the LN Kart brand with Lando Norris in 2021 and CS55 Racing with Carlos Sainz Jr. in 2024. In 2020, OTK acquired Gillard—the only British brand to win a non-superkart World Championship—and established EOS Racing Kart. OTK has operated factory-backed teams with the Tony Kart, Kosmic, and Exprit brands.

A 70% stake in OTK was acquired by QCapital and BIC Capital in 2022, supported by Crédit Agricole Italia, with the Robazzi family retaining 30% and strategic control. By 2023, OTK generated over 90% of its sales outside of Italy, with subsidiaries located in the United States, Japan, and Singapore, utilising over 130 distributors in 70 countries with million in revenue. In 2023, OTK acquired Vega Tyres, which produced over one million tyres per year, representing 40% of the competitive tyre market. Two years later, it merged with TM Kart, an engine manufacturer with 19 World Championships, 15 of which were in the gearbox categories; the Flenghi family of TM subsequently joined the ownership group of OTK. It further strengthened partnerships with OMP Racing and Hitech Grand Prix throughout the mid-2020s, the latter following their collaboration with KTR in Formula Renault 2.0.

Facilities OTK operates a factory in Prevalle, where it produces all its chassis and engines under various brands. The karts are frequently tested at South Garda Karting in nearby Lonato del Garda.

Chassis Brands

Tony Kart (1958–present) Kosmic (1996–present) Redspeed (2004–present) Exprit (2009–present) EOS (2020–present) Gillard (2020–present; acquisition) LN (2021–present) CS55 (2024–present)

Former Trulli (1997–2003) FA Kart (2009–2020)

Engines Vortex Engines

Vortex Engines is the engine division of OTK. Founded in 1995, Vortex operate the ROK line of engines, which are contested in single-manufacturer disciplines worldwide.

TM Kart In 2025, OTK merged with TM Kart, an engine manufacturer with 19 World Championships, 15 of which were in the gearbox categories.

Tyres During the pre-2012 open tyre era, Tony Kart were primarily partnered with Bridgestone. Of its 16 World Championships during the era, 14 were won on Bridgestone tyres, with one title on Vega tyres and another on Dunlop tyres.

Vega Tyres In 2023, OTK acquired Vega Tyres, which produces over one million tyres per year, representing 40% of the competitive tyre market. Vega was founded in 1976 by Sergio Mantese in Saronno, Lombardy, Italy, and its tyres were used to win six World Championships throughout the open era.

World Championships

OTK has won 35 CIK-FIA World Championships—23 with Tony Kart chassis, four with FA Kart chassis, five with Kosmic chassis, and three with Exprit chassis; 24 of which were with Vortex engines—since the inaugural edition in 1964:

+ClassYearChassisEngineTyresDriver1FC1986Tony KartPavesi Fabrizio Giovanardi2FA1991Tony Kart (2)Rotax Alessandro Manetti3FA1992Tony Kart (3)Rotax Nicola Gianniberti4FC1994Tony Kart (4)Pavesi Jarno Trulli5FA1995Tony Kart (5)Italsistem Gastão Fráguas6FA1996Tony Kart (6)Vortex Jean-Christophe Ravier7FSATony Kart (7)Vortex Johnny Mislijevic8FA1997Tony Kart (8)Vortex James Courtney9FA1998Tony Kart (9)Vortex Ruben Carrapatoso10FSATony Kart (10)Vortex Davide Forè11FA1999Tony Kart (11)Vortex Franck Perera12FSA2000Tony Kart (12)Vortex Davide Forè (2)13FA2004Tony Kart (13)Vortex Davide Forè (3)14FA2006Tony Kart (14)Vortex Davide Forè (4)15KF12007Tony Kart (15)Vortex Marco Ardigò16KF12008Tony Kart (16)Vortex Marco Ardigò (2)17KF12012Tony Kart (17)Vortex Flavio Camponeschi18KF-J2013Tony Kart (18)Parilla Alessio Lorandi19KF-J2014FA KartVortex Enaam Ahmed20KFFA Kart (2)Vortex Lando Norris21KZTony Kart (19)Vortex Marco Ardigò (3)22KF-J2015FA Kart (3)Vortex Logan Sargeant23KFKosmicVortex Karol Basz24OK-J2016Kosmic (2)Parilla Victor Martins25OK-J2017ExpritTM Dexter Patterson26KZ2018Kosmic (3)Vortex Patrik Hájek27OK-JKosmic (4)Parilla Victor Bernier28OK-J2019FA Kart (4)Vortex Thomas ten Brinke29OK-J2020Kosmic (5)Vortex Freddie Slater30OKTony Kart (20)Vortex Callum Bradshaw31KZ2021Tony Kart (21)Vortex Noah Milell32OK-JExprit (2)TM Kean Nakamura-Berta33OKTony Kart (22)Vortex Tuukka Taponen34OK-J2022Tony Kart (23)Vortex Enzo Tarnvanichkul35OK-J2023Exprit (3)TM Dries Van Langendonck36KF11900chassisnameenginename drivernameSource:+ Bridgestone LeCont C Carlisle Maxxis Dunlop MG Tires Goodyear M Mojo Komet Vega

Notes

See also Commission Internationale de Karting Kart racing List of kart manufacturers

References

External links Tony Kart Vortex Engines Kosmic Kart Redspeed Kart Exprit Kart EOS Racing Kart Gillard Kart LN Racing Kart CS55 Racing Kart TM Kart QCapital