Rotax DD2, the Challenge: 3 rookies take on the Champion

As many people involved in karting know, the Rotax DD2 represents a unique proposition in today’s karting landscape: a machine powered by the powerful and reliable Rotax 125 engine, featuring two gears operated from the steering wheel via paddle shifters and front brakes controlled by a pedal. It is a kart capable of combining high performance with an extremely technical driving experience, without the extreme physical demands typically associated with KZ karts. It is suitable for drivers aged 15 and above, with a particular appeal for Gentleman drivers, Sim Racing competitors, and enthusiasts looking to experience the thrill of a real racetrack in a true high-performance racing kart. Naturally, for those with competitive ambitions, the RMC framework offers dedicated categories: DD2 (for drivers aged 15 and over) and DD2 Master for drivers over 35.

 

For our test day, in addition to two official magazine testers, we brought three drivers selected from three different karting backgrounds: the OK-N category, a well-known Italian two-stroke one-make championship, and a four-stroke one-make series. We made sure that none of the drivers—all over 40 years old—had ever driven a gearbox kart, whether KZ or DD2, before. Leaving you to enjoy the full video, which explores in detail the impressions of the newcomers and tells the story of how they managed to find their limits in just a single test day, we can offer a few useful tips for anyone interested in approaching this category.

The Chassis
Choosing a chassis specifically designed for DD2 is often the most sensible solution. A DD2 chassis closely resembles a KZ chassis, differing only in a few details, as DD2 chassis tend to be slightly stiffer in the rear section than their equivalent KZ or single-speed versions.
In DD2, the engine is mounted directly to the chassis and does not use an adjustable engine mount as found in KZ or single-speed categories. In addition, the drive sprocket is positioned very close to the central axle bearing. For this reason, the third bearing carrier (the central one) is generally more robust, designed to withstand higher loads and, in some cases, welded or reinforced differently compared to the KZ version of the same chassis.

 

While it is certainly possible to adapt a KZ chassis to fit a DD2 engine, our recommendation is to choose a chassis originally designed for DD2. There is a healthy supply of used examples on the market, particularly following the Grand Finals. Such chassis offer clear advantages, including a properly engineered central axle support and, in some cases, setup solutions already developed by the manufacturer specifically for the category, which—as our testers quickly discovered—features a very sharp response on corner exit and under acceleration. On track, especially at fast circuits such as Franciacorta where the karts exceeded 130 km/h (a KZ typically reaches around 135–138 km/h), the DD2 delivers driving sensations reminiscent of a race car thanks to the presence of front brakes, while still retaining all the immediacy and engagement that make karting unique. The absence of suspension means every reaction remains highly direct, but compared to a KZ, the physical effort required is significantly lower, allowing even less-trained drivers to complete a full day on track without particular difficulty.

The challenge organized during the test provided a concrete opportunity to evaluate the category’s potential. Under the supervision of Rotax technicians, who assisted participants both during track sessions and with setup adjustments between runs, the drivers also benefited from telemetry analysis carried out using Starlane Corsaro II-R systems and the dedicated software package.

 

At the end of the day, a coaching session based on the collected data highlighted some very interesting results: three drivers experiencing a DD2 for the very first time managed to keep the gap within one second of the day’s benchmark, represented by a Rotax Grand Finals winner.

The recorded lap times confirm the level achieved by the participants when compared to the best lap set by 2024 Sarno Rotax Grand Finals winner Xen De Ruwe: 48.68 seconds (top speed 132 km/h):

• Guido Pedrotti: 50.70 s – top speed 128 km/h
• Thomas Daniel Brundu: 49.08 s – top speed 128 km/h
• Filippo Fiorini Miotti: 49.14 s – top speed 130 km/h

The figures from our day on track, along with the rapid adaptation shown by our “testers for a day,” demonstrate how the DD2 can serve as an excellent gateway into high-performance karting, offering an appealing balance of competitiveness, accessibility, and running costs.