All the details (and secrets) of the Sodi Sigma KZ powered by the TM Kart KZ-R2, World Champion

2025 will be remembered as a landmark year for the manufacturer Sodikart. The chassis produced by the French company based in Couëron (in north-western France) and marketed under the Sodi brand secured all the main FIA Karting titles in the Shifter categories: the KZ European Championship, the KZ2 European Championship and the KZ2 World Cup. The most anticipated victory, however, arrived on the weekend of 9–12 October at the Franciacorta Karting Track in Castrezzato (Italy), where Dutch driver Senna Van Walstijn (born 2003) claimed the KZ FIA Karting World Championship, the most important event of the year for the Shifter categories. He achieved this result at the wheel of a Sodi Sigma KZ chassis equipped with a TM Kart KZ-R2 engine prepared by SANI Competition and LeCont LPM CIK Prime tyres. It was a fully deserved success, achieved over a weekend held entirely in dry conditions, with high humidity and ambient temperatures ranging from 16 to 22 °C. In the final, held on Sunday 12 October at 15:45 with an ambient temperature of around 20 °C, Van Walstijn, starting from third position, took the lead on lap three and crossed the finish line with more than one second of advantage over his closest pursuer, Viktor Gustafsson (CRG/TM Kart/LeCont).

At the end of the final, in parc fermé, we were granted exclusive access to the chassis that won the 2025 KZ World Championship. With the support of the Sodikart and SANI Competition technicians on site, we examined every section of the Sodi Sigma KZ, documenting the components used and the technical choices that enabled Senna Van Walstijn to secure his first world title.

Editorial note
In the photo on the previous slide, from left: the Sodikart mechanic (Tony Lavanant), Flavio Sani (owner and founder of SANI Competition) seated in the kart, and the 2025 KZ World Champion Senna Van Walstijn.

Senna Van Walstijn at the finish line of the 2025 KZ World Championship Final at the Franciacorta Karting Track.

The 2025 World Champion Sodi Sigma KZ chassis, without the engine, photographed by the TKART team in parc fermé at the Franciacorta Karting Track immediately after the final.

During the competition, the Sodikart team had six LeCont CIK LPM Prime tyres available, to be managed from qualifying through to the Super Heats. For the final, as required by the regulations, an additional set of new tyres (slicks in this case) was supplied.

The Franciacorta Karting Track is a 1,300-metre layout with a width varying between 8 and 10 metres. It alternates high-speed, load-bearing corners with slow hairpins that demand firm braking and precision in traction management. The 13 corners – eight right and five left – create a configuration which, in KZ, a category where very tight lines are driven, makes overtaking particularly challenging. The asphalt, known for its high grip, rubbers in quickly, producing significant evolution in adhesion throughout the sessions and directly influencing setup adjustments.

Senna Van Walstijn on the podium of the 2025 KZ World Championship at the Franciacorta Karting Track as he lifts the winner’s trophy.

ALL THE DETAILS (AND SECRETS) OF THE SODI SIGMA KZ POWERED BY THE TM KART KZ-R2, WORLD CHAMPION