NEW SPOILER AND FRONT PANEL KG 509, 10 NEWTONS LESS DRAG AT 80 KM/H!
Aerodynamic research in karting is entering an increasingly advanced stage of development. In recent years, we have seen the introduction of increasingly sophisticated fairings and devices. In this sense, we have become aware of the fact that, even if karting does not reach high peak speeds like in other motorsport disciplines, small aerodynamic adjustments can bring benefits both in terms of reducing aerodynamic resistance and in terms of increasing vertical load on the wheels, without having to sacrifice anything in other parameters (such as weight, for example). It is precisely in this direction that the work carried out - on the occasion of the new FIA Karting 2025-2027 homologation cycle - by KG, which has long been committed to the development of increasingly high-performance aerodynamic solutions, fits in: "We focused on the front - says Davide Gaggianesi of the KG research and development team - still seeing a bit of room for improvement with the current regulations in terms of reducing aerodynamic resistance. The area where the driver is 'uncovered' is the one where there is a bit more room for work".
The development of the new kit lasted about a year and a half and was carried out using CFD (Computational fluid dynamics) software applications, which allow the simulation of the dynamic behavior of the air flow, and the wind tunnel to validate the results and to be able to carry out practical tests quickly. A research and development process completely similar to that carried out in other motorsport categories, such as GT and Formula. The research and development activity undertaken by the KG team concerned two main areas: the reduction of aerodynamic resistance to advancement and, furthermore, a more efficient and homogeneous distribution of the vertical aerodynamic load on the two axes of the kart. During the development phase, seven prototypes were tested in CFD and three final solutions in the wind tunnel, before arriving at the definitive model. As happened for the design of the 508 and 507 models, KG availed itself of the collaboration of BeonD, an Italian company, based in Turin, specialized in consulting and supplying research services for the automotive industry and able to offer engineering services with the most up-to-date design and simulation techniques.
Front Panel KG 509 (homologation FIA Karting 003-BP-11)
Compared to the KG 508 front spoiler, the new KG 509 model (FIA Karting 003-BP-11 approval) introduces two main changes. The first concerns the lowering of the air duct entry point by approximately 100 mm: this evolution was designed to reduce the pressure coefficient (CP) that was generated in the initial area of the Venturi duct in the 508 model (as highlighted in the image in the “Genesis” section). The Venturi duct, already present in the previous spoiler, but now positioned lower and approximately 85 mm longer, exploits the Bernoulli principle: by narrowing the passage section, it accelerates the air flow and reduces its pressure. The air is then diverted upwards, over the driver’s body and helmet, thus contributing to the reduction of aerodynamic resistance (drag) in that area. The second change, even more evident, concerns the insertion of the so-called “shark gills”, i.e. five horizontal slits along the length of the spoiler. The “gills” are used to vent the air inside the tunnel, ensuring the right blowing. As Davide Gaggianesi explained, “The ‘shark gills’ are absolutely not casual or aesthetic. Without them, in the first prototypes an internal recirculation zone was created, which would have compromised the good blowing of the tunnel. These situations are very damaging, because they create a plug effect, preventing the duct from working. From here we came up with the idea of adding the ‘gills’ to remove the recirculation area and make the flow, both internally and on the back of the spoiler, very laminar and fast”.
KG 508 front panel
Weight: 1.010 gr (with screws), without supports
Front spoiler KG 509 (FIA Karting 003-BF-09 homologation)
Like the nassau panel, the KG 509 spoiler (FIA Karting 003-BF-09 approval) mainly introduces two important innovations compared to the previous KG 507. The first concerns the central part, which is slightly more hollowed out to facilitate the entry of air into the mouth on the front panel, thus improving the flow towards the Venturi duct. The second innovation concerns the two lateral areas: the Italian company has in fact adopted innovative lateral air vents called “air curtains”, which have the purpose of directing the air flow outside the front wheels. The advantage is that of creating an air cushion that reduces the turbulence generated by the rolling of the wheels, as well as reducing the air pressure areas on the side of the side fairings. Thanks to this measure, as visible from the results of the CFD analysis, the rear wheel area also benefits, in fact there is a decrease in the high pressure areas that generate aerodynamic resistance. This is an innovative concept that has recently been used in the automotive sector, on the front bumpers of sports or racing cars. The concept is to "seal" the external part of the wheels not with a physical element - an eventuality prohibited by the FIA Karting regulations - but through an air flow that is as laminar as possible. The inlet area and the geometry of the section of these vents have therefore been optimized to generate a fast, laminar air flow directed outwards. Finally, compared to the previous KG 507 spoiler, there is a further raising of the fairing in the foot area, to obtain better coverage.
KG 509 front spoiler
Weight: 1.9000 gr, without bumpers
educing drag: the improvements recorded
As regards the reduction of aerodynamic resistance to advancement, the main task of the duo composed of the front panel and the KG 509 spoiler is to divert the air flow coming from the front in the best possible way, trying to cover the driver's silhouette as much as possible, which increases the area of the frontal section and generates very large areas of turbulence. In particular, the sensitive areas are the helmet, shoulders and arms. In the past, the driver's feet were also exposed to the frontal air flow, while today they are completely covered by the spoiler. As regards the extension of the fairings in order to "cover" the driver, however, the FIA Karting technical regulation (art. 9.5.3 of the Technical Regulations) establishes that the spoiler cannot exceed the upper edge of the steering wheel in height, preventing effective "coverage" of the shoulders and head. In this sense, the torso, including the shoulders and arms, is the one that offers the highest resistance, having a very large area and perpendicular to the direction of advancement. The new KG 509 nassau front spoiler has made it possible to significantly reduce the pressure areas on the chest and arms, further improving the already excellent situation offered by the KG 508. With the KG 509, the Italian company's technicians also focused on reducing the impact of the fairing surfaces themselves. As Davide Gaggianesi of the KG Karting research and development team explains, "It's useless to protect the driver if there's a wall in front of him. The driver won't resist, but what's in front of him will. It's therefore necessary to have the smallest possible flat frontal surface." As for performance, the advantages offered by this new configuration are confirmed by the data collected in the wind tunnel (which validated the indications obtained with the CFD simulations): the aerodynamic resistance at 80 km/h is reduced by about 1 kg, or 10 N in terms of force. It is important to underline that this already significant value grows proportionally to the square of the speed: this means that, at higher speeds - for example over 100 km/h - the drag reduction guaranteed by the new kit takes on an even more significant impact in terms of overall performance.
Vertical load distribution: the improvements recorded
Reducing aerodynamic resistance is always beneficial for a kart, but the generation of downforce must be managed carefully. Excessive load on a single axle can unbalance the vehicle and compromise its driveability. For example, a spoiler that produces 100 kg of downforce at 100 km/h on the front alone can cause a spin in a corner due to a lack of grip at the rear. In developing the new KG 509 nassau panel and spoiler, attention was focused on the correct distribution of the load between the two axles of the vehicle. Thanks to the use of a wind tunnel equipped with dedicated scales on the front and rear axles, it was possible to precisely measure the distribution of the aerodynamic load, through the analysis of the Cz coefficient (where C indicates the coefficient and z the vertical axis), which expresses the vertical force exerted on the wheels as a function of speed. The design goal was to achieve a more balanced distribution, avoiding excessive concentration of downforce on the front axle, where it is easier to generate it. A homogeneous distribution allows for improved road holding on both axles as speed increases, reducing the risk of instability at high speeds. This principle applies across the board in motorsport, where the aim is to position the point of application of the overall aerodynamic load — called the Center of Pressure (CP) and different from the pressure coefficient analyzed previously — as far back as possible at high speeds, to promote more predictable and understeering behavior. Unlike other categories, however, a racing kart does not have rear wing profiles, making it more difficult to move the load towards the rear. This is precisely why the work done by KG is fundamental. The results relating to balance were detected in the wind tunnel, where a load of 54% was measured on the front axle with the new KG 509 kit. With the previous KG 507 and 508 kits, keeping the driver unchanged — a factor that also affects the balance of the vehicle — the load was equal to 58%.
To take full advantage of the aerodynamic benefits offered by the new KG 509 nassau panel and spoiler, the Italian company recommends taking some precautions during their installation on the kart. We list them in the images in this slide.
