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 68-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.[1][2][3] Bosio’s craftsmanship was admired by drivers, who frequently visited his workshop.[4] 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 214.286 km/h (133.151 mph).[5][6] Bosio also collaborated with the Italian Winter Sports Federation (FISI) on the construction of bobsleighs.[7] His work was credited with several innovations in kart design, such as the “floating” brake caliper.[4]
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.[1] 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.[8] 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.[8] 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.[9][10]
OTK expanded beyond the Tony Kart brand in the mid-1990s. In 1995, it founded Vortex Engines, evolving Tony Kart into a factory team.[11][12] 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.[13][14][15][1][16] From 2009 to 2020, OTK partnered with two-time Formula One World Drivers’ Champion Fernando Alonso on the FA Kart chassis.[17][18] It later established the LN Kart brand with Lando Norris in 2021 and CS55 Racing with Carlos Sainz Jr. in 2024.[16][19][20] In 2020, OTK acquired Gillard—the only British brand to win a non-superkart World Championship—and established EOS Racing Kart.[21][22][23] OTK has operated factory-backed teams with the Tony Kart, Kosmic, and Exprit brands.[24][13][15]
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.[25][26][27] 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 €45 million in revenue.[25] In 2023, OTK acquired Vega Tyres, which produced over one million tyres per year, representing 40% of the competitive tyre market.[25][28] 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.[27][22] 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.[29][30][31]
Facilities
OTK operates a 17,000 m2 (180,000 sq ft) factory in Prevalle, where it produces all its chassis and engines under various brands.[32] The karts are frequently tested at South Garda Karting in nearby Lonato del Garda.[33]
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)[a]
- CS55 (2024–present)[b]
- Former
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.[12]
TM Kart
In 2025, OTK merged with TM Kart, an engine manufacturer with 19 World Championships, 15 of which were in the gearbox categories.[27][22]
Tyres
During the pre-2012 open tyre era, Tony Kart were primarily partnered with Bridgestone.[8] 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.[25] 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.[25][8]
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:
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Notes
- ^ Collaboration with Lando Norris.
- ^ Collaboration with Carlos Sainz Jr.
- ^ Collaboration with Jarno Trulli.
- ^ Collaboration with Fernando Alonso.
See also
References
- ^ a b c “Tony Kart”. Rod Van Deusen Motorsports. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ “Antonio Bosio | Kartpedia”. TKART. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ “Farewell “Tony” Bosio, Mr. Tony Kart”. Vroomkart. 12 June 2015. ISSN 1724-9147. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ a b Perrone, Riccardo (23 February 2011). “Storia – Tony Brosio” [Story – Tony Brosio]. KartClassic (in Italian). Archived from the original on 11 November 2013. Retrieved 9 June 2026.
- ^ “214 km/h with a 100cc kart at Monza”. TKART. 8 March 2018. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ “Il Karting in Italia e gli albori della FIK” [Karting in Italy and the dawn of the FIK]. Federazione Italiana Karting (in Italian). Automobile Club d’Italia. 10 June 2010. Archived from the original on 9 March 2012. Retrieved 9 June 2026.
- ^ Buttazzoni, Cristian (12 June 2015). “Addio ad Antonio “Tony” Bosio, fondatore di Tony Kart” [Farewell to Antonio “Tony” Bosio, founder of Tony Kart]. Tutto sui Motori (in Italian). Archived from the original on 5 July 2015. Retrieved 9 June 2026.
- ^ a b c d e Voltini, Maurizio (January 2016). “Special – CIK-FIA Hall of Fame 1964–2015”. Vroomkart. Vol. 175. pp. 32–34. ISSN 1724-9147.
- ^ Sterzel, Yanek (10 March 2016). “Driving Schumi’s kart”. TKART. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ “Schumacher & Schumacher on Tony Kart–Vortex”. Vroomkart. 11 March 2011. ISSN 1724-9147. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ “12 engines that wrote Vortex history”. TKART. 29 May 2020. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ a b Josue, Diego (20 June 2025). “Types of Vortex Engines”. Kart Class. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ a b “Kosmic Kart | Kartpedia”. TKART. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ “Redspeed Kart | Kartpedia”. TKART. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ a b “The new Exprit Racing Team is born”. Vroomkart. 20 December 2019. ISSN 1724-9147. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ a b “LN Racing Kart by Lando Norris launch photos”. Kartcom. 30 September 2021. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ “Margutti, forever Margutti”. Vroomkart. 19 February 2009. ISSN 1724-9147. Archived from the original on 8 January 2026. Retrieved 8 January 2026.
- ^ Alvarez, Guillaume (11 November 2020). “Kart Republic confirms new Alonso Kart chassis line and team for 2021 (update)”. The RaceBox. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ “LN Four Is Born, Lando Norris’ Kart Made In OTK Kart Group”. Vroomkart. 29 September 2021. ISSN 1724-9147. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ “Carlos Sainz on Track with The New CS55 Racing Kart by OTK”. eKartingNews. 6 February 2024. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ Billet, Frédéric (April 2021). “The Gillard brand joins OTK Group” (PDF). Kartcom News. Vol. 63. Kartcom. p. 21. Archived (PDF) from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ a b c d “World Karting Legends”. Kartcom. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ “EOS, the new brand made in OTK Kart Group”. Kartcom. 5 February 2020. Archived from the original on 10 June 2026. Retrieved 9 June 2026.
- ^ Opong, Rich. “Tony Kart Go-Karts: History And Reviews Of 3 Karts”. Flow Racers. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ a b c d e “OTK Kart Group and Vega merge!”. Kartcom. 18 October 2023. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ “The Robazzi Family chooses QCapital and BIC Capital to accelerate the growth of OTK Kart Group”. Vroomkart. 30 June 2022. ISSN 1724-9147. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ a b c “Green light for the partnership between OTK Kart Group and TM Kart”. TKART. 19 September 2025. Archived from the original on 10 June 2026. Retrieved 10 June 2026.
- ^ “OTK Kart Group and Vega: union between two big names in karting world”. TKART. 6 October 2023. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ “OTK Kart Group strengthens partnership with Racing Force Group”. Tony Kart. OTK Kart Group. 23 October 2025. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ Wood, Ida (12 December 2025). “FIA launches global karting shootout as Hitech partners with Tony Kart”. Formula Scout. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ “Tony Kart Racing Team with KTR in Formula Renault 2.0”. Vroomkart. 16 January 2012. ISSN 1724-9147. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ “OTK Kart Group”. QCapital. Archived from the original on 9 June 2026. Retrieved 9 June 2026.
- ^ Kaligis, Bas (17 October 2019). “Video: Sebastian Vettel testing in Lonato for Tony Kart”. KartXpress. Archived from the original on 9 June 2026. Retrieved 9 June 2026.