2026 Beta RX 450 4T

The RX 450 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 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 RX 450 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 RX 450 has four throttle pulleys so riders can tailor the throttle response.

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.
• Featuring graphics with a modern race look, simple yet bold, the final touch to the Italian RX range.
• Radiators are structurally strengthened to prevent deformation, even during heavy use.
• Aluminium subframe offering light, yet stiff structure with the rigidity to overcome the demands of motocross.
• Kayaba 48mm forks and 50mm shock, calibrated specifically for MX applications.
• Access to the air filter remains unchanged and is tool free. Kayaba 48mm forks 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 RX 450 4T also offering four levels of Traction Control.

The RX 450 is delivered with 4 different pulleys to customise the throttle response.