TM Kart unveils its new range of CIK-FIA homologated engines

As the 2026–2028 FIA Karting homologation cycle approaches, the Italian manufacturer has renewed its entire range of engines for both international and national categories, from MINI to Shifter, including the OK classes.

TM Kart presents its engines for the 2026–2028 period: KZ-R3, MINI 4/4B, OK S3-Senior, OK S3-Junior, and OK S3-OKN. Building on a product line already renowned for performance and reliability, TM Kart has introduced new technical solutions to further enhance the standards of its power units. All engines are designed and manufactured entirely in-house and aimed at the global market.
The vast amount of data collected on track—through both factory racing operations and TM Kart’s worldwide dealer network—feeds a continuous process of research and development. Supported by skilled technicians, CAD-based design, extensive bench testing, and precision machining on state-of-the-art five-axis equipment, TM Kart keeps refining its engines without altering the proven foundations that have made them front-runners in both national and international competition.

KZ-R3: innovation and continuity
The new KZ-R3, also available in the Total Black version, embodies TM Kart’s philosophy for engines developed under the 2026–2028 CIK-FIA homologation cycle. Innovation and continuity define this engine designed for the KZ, KZ2, and KZ2 Masters classes—the gearbox categories regulated by FIA Karting.
Evolving from its predecessor, the KZ-R2, which collected two World titles, seven European titles, three World Cups, and three International Masters Super Cups in just three years, the KZ-R3 refines all the strengths that made the previous model so competitive while introducing key updates to increase its potential.
Among the major improvements is a new, more compact clutch assembly capable of transmitting higher torque, improving both reliability and performance. Mechanical efficiency has also been boosted with a redesigned primary gear ratio, the result of detailed development work on tooth profiles and revised gear values.

MINI 4/4B: a redesigned concept
TM Kart has also implemented significant updates to its new MINI 4/4B engine, designed for the MINI 60 cc class under FIA Karting regulations. Succeeding the MINI 3/3B, a proven winner in WSK competitions, the new unit features a redesigned cylinder head and barrel with optimised cooling fins for improved heat dissipation.
These changes stem from in-depth CFD thermal analysis, which also led to the creation of new plastic shrouds to maximise airflow around the hottest areas of the engine. Additional refinements include a newly developed intake duct that enhances overall performance and upgraded crankshaft seals that reduce power losses caused by internal friction.

OK S3: technical continuity serving performance
The philosophy of continuity pursued by TM Kart for the 2026–2028 homologation cycle is particularly evident in its Direct Drive range for the Junior and Senior classes: OK S3-Senior, OK S3-Junior, and OK S3-OKN.
The engines used in the international FIA Karting OK and OK-Junior categories, as well as those in the national OK-N and OK-N Junior classes, retain their core specifications, with TM Kart extending the homologation of each model. Meanwhile, engineers have analysed on-track data in detail to fine-tune every performance aspect.
World Champion in 2023 and European Champion in 2024, the OK S3-Junior stands out for its smooth, progressive power delivery. Alongside it, the OK S3-Senior, a two-time European Champion, benefits from the latest developments in mechanical design, fluid dynamics, and thermal stability.
Developed according to the same engineering principles, the OK S3-OKN has also confirmed its competitiveness, winning the OK-N Junior World Cup and finishing second in OK-N.

Performance, reliability and simplicity: the TM Kart signature
The constant pursuit of performance, reliability and ease of maintenance remains at the heart of TM Kart’s philosophy.
With this new range, the Italian manufacturer reaffirms the competitiveness of its entire line-up for the CIK-FIA 2026–2028 homologation cycle, consolidating once again its position as a benchmark in international karting.

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