RX 4T 450 MY26

RX 4T 450 MY26


RX 450 4T MY 2026


Beta lands on a new fun dimension, with the new RX My2026, proving to believe in the MX project like never before. It expands its line and lays new foundations to develop a complete 2- and 4-Stroke model range.

Two all new models that will revolutionize the 2Str market join the updated RX 450 for MY26, as announced at EICMA, during the new Champions Charity Race with MotoGP and racing legends, the 2Str range welcomes the new 350cc engine, also joining the 2 Str RX family is the race-inspired RX 250! The only thing left to do is choose one and hit the track for some fun!

So, what does having fun on a Beta mean? One word, RideAbility. Each Betamotor-branded motorcycle is designed by the Italian manufacturer to provide any rider with a bike which is simultaneously easy to ride yet high in performance. A product able to get all the best from any rider, thanks to an engine-frame combination which is able to provide a fun ride, without reason to ever fear the world championship-level performance of the engine, making RideAbility its core value.

RX 450 4Str is the fans’ chance to ride a Made-in-Beta MX closely resembling the race bike that’s been running in the MXGP World Championship for five years now and in the American AMA Supercross series since 2024. The Model Year 2026 RX 450 has been updated with a massive performance step, making the power delivery close to that of the factory bikes, while keeping the brand’s signature ease of control intact.

Let’s go over each model in detail:

RX 450 4T

Engine: the 450cc engine development was focused on providing riders a significant performance increase compared to the previous model, offering a stronger torque curve that can be used under all 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 increase their fill 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.

Exhaust system: the head-pipe has been redesigned to create a greater flow and to provide increased power. This new 4Str exhaust system is completed by a silencer, redesigned with HGS to contain the DB output, in line with the new racing standards.

Map: maps were updated to fair better with the new motor configuration, with renewed start-up and limiter strategies.

The following elements are confirmed on the entire range:

Frame: geometry remains unchanged, yet the frame now incorporates a cast-in brace to further strengthen the frame around the steering neck area. This increases the reliability and stiffness of the frame’s area most subject to stress.

Aluminium rear sub-frame and dedicated filter box: aluminium gives the right level of stiffness to the structure. Light, yet has the rigidity to overcome the demands of motocross. Access to the filter remains on the left side of the bike, and is extremely easy and intuitive, as well as being tool free. The push button seat also removes without tools.

Kayaba suspensions: fork (48mm) and single shock (50mm) are specifically calibrated on the new range models, focusing on their rideability and stability when the pace rises. The resulting setting is enough to make any rider confident, from amateurs to professionals.

Nissin braking system: with floating callipers and 260mm Galfer discs at the front and 240mm at the rear, for powerful and modular braking.

Chain: non o-ring, lighter and smoother.

Lithium battery: lighter and a must for quick starts.

Handlebar silent block: Xtrig Flexfit bar mounts provide a comfortable grip on the handlebar for enhanced control and reduced vibration.

To complete our round-up of the bike:

Engine maps: all the RX models are equipped with two specific engine maps (wet and dry), while the 4-Stroke model has also four levels of Traction Control (on/off/active with hard map/active with soft map) to manage the vehicle's significant power in all terrain conditions. The button to select the map and TC is located on the handlebar bumpers.

All RX will be supplied with personalized kickstand. In addition, the 4Str has four different throttle pulleys to customize the accelerator’s response.


TECHNICAL DATA

Chassis

Max Height 1270 mm
Frame Molybdenum steel with double cradle split above the exhaust port
Wheelbase 1485 MM
Max Length 2170 MM
Max Width 825 MM
Seat Height 945 mm
Ground Clearance 330 mm
Footrest Height 410 mm
Dry Weight 104,5 kg (front 51,4 kg; rear 53,1 kg)
Fuel Tank Capacity 7.0L
Front Suspension Hydraulic USD fork with ø48 mm shaft
Rear Suspension Monoshock with progressive compound lever

Engine

Type Single cylinder, 4-stroke, liquid-cooled
Bore 97 mm
Stroke 60.8 mm
Displacement 449,3 cc
Starter Electric starter
Fuel System Elldor dual electronic injection
Lubrication DOHC finger follower / 4 valve, intake titanium, exhaust steel
Clutch Wet multi-disc clutch
Transmission 5 Gears
Engine Oil SAE 10W/50