2025 Beta RX 300 MX

RX 450 4T

Rear sub-frame and filter box: while the rear sub-frame's geometry and the filter box remain the same, the structure has been suitably reinforced in a series of points that stiffen and strengthen it, maintaining lightness and ability to absorb stresses. Access to the filter remains on the left side of the bike, and is extremely easy and intuitive, as well as being tool free.
Suspension: fork and single shock receive a new calibration that enhances the bike's character, both in terms of handling and stability when increasing the pace. The result is an improvement of the features already highlighted by MXGP riders for this model - manoeuvrability and stability that instil confidence in every rider, regardless of their level.
Battery: for safe first-shot ignitions, even in the most severe conditions of use, a new lithium battery has been mounted on RX MY25, with an amperage higher than the previous one, to always have the necessary starting power.
Final ratio: to find the ideal compromise between speed and acceleration, the rear sprocket now has 51 teeth - one more than the previous model – to improve the engine response coming out of corners as well as allowing the engine to build RPM quicker.
Graphics: while the superstructures recently introduced with the new tail remain unchanged, new, more sleek and aggressive graphics have been introduced, which do not lack character in highlighting the racing soul of the model.

The RX 450 already received interesting updates with the new Model Year, all the new features introduced on the RX 300 2T model from Beta are truly a surprise, with the following elements radically enhanced:

Frame: as in the 450, the RX 300 also gets the new frame, specifically dedicated for motocross use, retaining many known proportions from Beta models but with a series of specific redesigned and reinforced parts compared to standard Enduro models. Getting even with the 4T model, the frame acquires a wider main spar than in the past (1 cm more), which does not fear the stresses coming from repeated jump landings, resulting overall much stiffer in the lateral twists generated by high-speed bends. This translates into a precise, stable speed both entering and leaving corners, and which conveys a great feeling of safety in keeping the high performance of the engine tamed. The engine position and mounts are different from the Enduro models, and provide excellent balance both on corners and in jumps.
Rear sub-frame and filter box: in line with the use of the new frame, the new RX 300 inherits its older sister's aluminium sub-frame, as well as the filter box.
Fork: the Kayaba fork with 48 mm stems has greater travel than Enduro models, and receives a new calibration that recreates the perfect set-up together with the new single shock, ensuring a stable, fast and precise bike, yet always easy and precise in its response.
Single shock: the single shock is a new addition to this model, and, as for the 450, it switches to a 50 mm piston that allows greater support in jump landing, thanks to greater hydraulic braking, and guarantees constant performance with heavy use, where temperatures are on the rise. Braking system: Nissin with floating calipers and 260 mm discs at the front and 240 mm at the rear. Particularly at the front, the new caliper - inherited from its older sister - stands out; smaller, lighter and better performing than the previous one, it ensures a much better performance when letting off the throttle at the limit. At the rear, the new pump, featured for the first time on Enduro racing models, is characterised by greater braking power and greater modularity, as well as a different attachment to the frame.
Radiators: RX 450 also gives the new 300 2T its radiators, redesigned at the top compared to the previous model to have a better steering angle and optimize the cooling liquid's internal flow.
Final ratio: the rear sprocket has 49 teeth, instead of 48, for lightning-fast accelerations!
Plastic parts: while the front conveyors retain the same shape, the rear features a new, sleek and aggressive tail section that, not being a load-bearing element, engages in the new aluminium frame. The smaller plastic tank for the RX 300 now has a capacity of about 7lt.
Chain: the chain without o-ring is lighter and smoother than the previous one; all details that matter to make a difference on the track!
Engine and exhaust: if the bike is completely new suspension and frame-wise, the new engine features are even more game-changing, and bring the performance of the RX 300 to the top of its class. The totally new engine consists of a new cylinder with more exhaust and injection timing, a new head with greater compression, and modified intake crankcases to increase ventilation. The result of this intervention is a power unit with a significantly higher thrust than in the past, which still maintains the exceptional thrust at low speeds that has always distinguished Beta's 300 2T, despite the peak maximum power at high speeds being higher, as needed on a motocross track. The greater power of the engine is transmitted to the rear wheel by a totally redesigned 5-speed gearbox, with a specific gear spacing for MX use, and by a stiffer spring that preloads the clutch pack more to prevent slippage. This new ensemble has been perfectly tuned by dedicated mappings, new carburettor calibrations (Keihin PWK 38), and several springs on the appropriately adjusted exhaust valve. The exhaust system, also completely redesigned, offers a dedicated expansion and ashort silencer, in full Motocross style.