FIRST LOOK: BETA’S 2026 MX RANGE

Six months ago, when Beta used Europe’s EICMA motorcycle show to announce its intentions to produce all-new 250 and 350cc motocross models, the worldwide motorcycle market sat up and listened. In addition to the intriguing fact that Beta’s RX350 was set to become the only 350cc two-stroke production MX bike on the market, Casey Stoney kindly chimed in to showcase the pre-production machine (in dirt track guise) by cutting a few sideways laps aboard it with his old MotoGP rival, Valentino Rossi, at the notorious VR46 Motor Ranch in Italy. And from that point onwards, many Beta dealers have been inundated with enquiries. And orders!

This week, Beta unveiled details of its 2026-model RX250 and RX350 two-stroke weapons – confirming these MX models will in fact become a production reality, and join the RX450 four-stroke, which itself comes in for some major changes for 2026. The bikes are due to hit Aussie dealers in October, 2025, at prices that are yet to be announced. Meantime, here’s the PR from BetaMotor, which itemises the upgrades introduced to the Italian manufacturer’s expanded MX model line-up for 2026…

We are proud to announce a major expansion of BetaMotor’s motocross program, with the launch of the MY26 RX range, marking a bold new chapter in the brand’s off-road journey. With the introduction of two all-new two-stroke models and significant updates to the RX450 four-stroke, Beta continues to solidify its commitment to motocross innovation, performance and fun.

Following its global debut at EICMA, the RX350 2T was unveiled at the Champions Charity Race and piloted by Australian MotoGP legend, Casey Stoner, which caught the attention of riders across the globe. Alongside the RX350 2T, the new RX250 2T was also unveiled – two new models designed to shake up the two-stroke market. Today, those models become a production reality, and sit alongside the MY26 RX450 4T that sees major updates. The result is a motocross range that offers performance, reliability, and the signature Beta ‘RideAbility’ that empowers riders of all levels.

At the core of Beta’s design philosophy is RideAbility – creating bikes that are not only race-capable, but also accessible and enjoyable for riders of all skill levels. With this new RX line-up, Beta blends high-performance engineering with ride-friendly characteristics, ensuring riders get the most out of every ride.

BETA’S ALL-NEW 2026 RX350 & RX250 2T MODELS

The MY26 RX range is led by the new RX350 2T, replacing the MY25 RX300 2T. The MY26 RX350 2T is a never-before-seen configuration in motocross and is a true innovation in the two-stroke category. Developed to combine the agility and simplicity of a two-stroke with the full-bodied, linear power delivery of a four-stroke, the RX350 is ideal for riders seeking high performance paired with ease of use. Featuring a dual-spark head for smoother combustion, a purpose-built power valve system, and optimised crankshaft and piston configurations, the RX350 delivers robust power at any speed while remaining manageable and fun to ride.

Another new model for MY26 comes the RX250 2T; adding a lightweight, high-revving option for riders. With a completely new engine architecture, it offers explosive performance, nimble handling, and the ability to challenge in competitive race environments.

Here’s how these two all-new two-stroke models differ:

HEAD: The first noticeable difference when looking at the new engines is the dual-spark-plug head on the RX350 2T, while the 250cc relies on a classic single spark plug configuration. This differentiates the two motorcycles’ character even further, with the 250cc providing riders with a high-revving engine that competes with the likes of 250 4T bikes, while the 350cc delivers greater torque and a rounded delivery, enhancing its ease of recreational use, at lower speeds while still providing plenty of overall horsepower for race use.
CYLINDER, PISTON & POWER-VALVE: To further differentiate the two bikes (apart from the obvious engine capacity), BetaMotor engineers developed new cylinders and pistons, designed specifically for each engine. The power-valve was calibrated differently between the models by adopting different springs.
CRANKSHAFT: The two motorcycles have a different stroke, with the 250cc reaching 72mm and the 350cc reaching 73.6mm.
CRANKCASE: New engine crankcases, with different internals between the two capacities have been matched with each models’ crankshaft.
GEARBOX: Gearboxes are five-speed and shared between both models with the only difference being the final ratios of the sprockets – 13/50 for the 250 and a 13/47 for its big sister.
EXHAUST: Also new for both models and designed to enhance the features of both engines, exhausts differ in the internal silencer diameter (bigger on the 350cc).

UPGRADES – 2026 BETA RX450 4T

The RX450 4T is back for MY26 with a host of engine refinements that bring its performance closer than ever to the factory bikes competing in MXGP and AMA Supercross. The development of the 450cc engine focused on delivering a significant performance increase over the previous model, with a stronger, more usable torque curve across all riding conditions.

This achievement was possible due to a new cylinder head with a performance-enhancing piston, a new intake manifold and a different exhaust system. The head’s overhaul – developed through CFD analysis and many flow bench calibrations – includes the following:

An improved intake duct to enhance air circulation inside the engine.
The new manifold, following the flow line, has a longer internal horn to improve the tuning of pressure waves, and thus increasing volume while intaking air.
The piston includes new coatings to reduce friction and improve its performance.
A newly designed counter-balancer was introduced to contain vibrations and reduce rider fatigue.

The RX450 4T also features a new HGS exhaust system, co-developed with HGS to create greater flow and increased power. Engine maps have been reworked for the new motor, with new start-up and limiter strategies. The RX450 has four throttle pulleys so riders can tailor the throttle response.

SHARED UPGRADES – 2026 2T & 4T RX MODELS

GRAPHICS: A modern race look, simple yet bold; the final touch to the Italian RX range.
RADIATORS: Structurally strengthened to prevent deformation, even during heavy use.

SHARED FEATURES – 2026 RX MODELS

All 2026 RX models share the following upgraded features, ensuring consistency in quality and performance:

The frame now features a cast-in brace to further strengthen the frame around the steering neck area, increasing stiffness.
Aluminium subframe offering light, yet stiff structure with the rigidity to overcome the demands of motocross. Access to the air filter remains unchanged and is tool-free.
Kayaba 48mm fork and 50mm shock, calibrated specifically for MX applications.
Nissin brakes with Galfer discs (260mm front / 240mm rear) for powerful, modular braking.
Xtrig Flexfit handlebar mounts for enhanced comfort and vibration dampening.
Electric start with lithium battery, lighter and a must for quick starts.
Non O-ring chain, lighter and smoother.
Two engine maps (wet/dry) on all models, with the RX450 4T also offering four levels of Traction Control.