OTK Kart Group: The Tonykart Empire

Count the chassis in any top-level OK final and one factory usually accounts for the plurality of the grid — it just wears different stickers. Tony Kart, Kosmic, Redspeed, Exprit, EOS, LN, CS55: all of them roll out of the same 17,000-square-metre plant in Prevalle, Lombardy.

Origins

Tony Kart was founded in 1958 by Antonio "Tony" Bosio in Prevalle, in karting's first decade. The transformation came in 1983, when Roberto Robazzi and Carlo Cancarini bought the company. Under Robazzi, still chairman today, Tony Kart grew into the OTK Kart Group — a vertically integrated giant making chassis, components and, from 1995, its own Vortex engines.

The multi-brand strategy followed: Kosmic (1996), Redspeed (2004), Exprit (2009), EOS (2020), then driver-partnered badges LN Kart with Lando Norris (2021) and CS55 Racing with Carlos Sainz (2024). In 2022, investors QCapital and BIC Capital took a 70% stake, with the Robazzi family retaining 30% and strategic control.

How it shaped karting

OTK's influence runs through every layer of the sport:

• Factory racing: the Tony Kart Racing Team is the benchmark works operation in FIA Karting competition, and drivers who raced OTK machinery on the way up include Michael Schumacher, Sebastian Vettel, Jarno Trulli, Lando Norris and Logan Sargeant.
• Vertical integration: Vortex engines power OTK's assault on OK and the KZ gearbox classes, making OTK one of the few groups that can win a world title with its own chassis, engine and components.
• The ROK universe: Vortex's ROK engine line spawned single-make ROK Cup series worldwide, funnelling into the mass-entry ROK Cup Superfinal in Italy — OTK's answer to the IAME X30 and Rotax MAX ecosystems. Full background in our Vortex ROK class history.

The multi-brand trick matters competitively: rival teams can run OTK hardware without flying Tony Kart colours, which is why the group's real market share always exceeds what the livery count suggests. It also spreads risk: when one badge's works team has a lean season, another usually delivers, and the Prevalle production line wins either way. No rival — not Birel ART, not CRG — has replicated the breadth of that portfolio.

Today

OTK remains the reference point of the chassis market and a fixture at the front of WSK and FIA Karting fields, while the ROK Cup platform keeps expanding across the Americas, Europe and Asia. Few weekends pass without an OTK-built kart winning something significant somewhere, whether that is a world championship final in Europe or a ROK Cup national round on the other side of the planet.

In our data, ROK competition feeds the ROK Senior rankings, while OTK's factory campaigns shape the OK and KZ tables week to week. Superfinal week and the group's headline entries are tracked in the calendar — and if you filter the driver database by equipment, Prevalle's fingerprints are everywhere.