INTRODUCING MY27 BETA RX RANGE

Beta's first 250 four-stroke motocross bike arrives alongside sharpened versions of the RX 450 4T and the RX 250 and RX 350 two-strokes.

Beta has confirmed its motocross range for the 2027 model year, headlined by the bike riders have been waiting for: the all-new RX 250 4T. After cutting its teeth in high-level competition through 2026, the 250 four-stroke now joins the production line-up, giving Beta Motorcycles four distinct MX models for MY2027 — the new RX 250 4T, the established RX 450 4T, and the RX 250 and 350 two-strokes introduced last year.

The one constant is the philosophy behind it all. Every Beta is built to be both high-performing and easy to ride — a bike that pulls the best out of whoever's on it, with an engine and chassis matched so the performance is always something you enjoy, never something you fear. Beta calls it RideAbility.

RX 250 4T

The long-awaited 250 4T motocross offering from Beta has arrived. The RX 250 4T was built to win at a world-championship level while staying friendly enough for the weekend racer — featuring strong, progressive power, serious traction, and handling that rewards rather than punishes. Engine and chassis share nothing with the existing range; both are purpose-built for the new RX 250 4T.

It's a race-ready four-stroke developed to sit alongside the popular two-stroke, broadening Beta's 250 line-up for riders who want four-stroke character. Strong traction, sharp handling and easy power management make it a genuine option for anyone chasing top-level performance with the precision and consistency to back it up — whatever the conditions.

And it's all new. The RX 250 4T doesn't borrow from the rest of the range; it solves things its own way, with technical solutions specific to this model.

The Engine

The all-new 250 4T engine features a DOHC layout with the cam chain located on the right-hand side — different to the RX 450 4T engine platform. The timing system uses a quiet Morse-type chain driven by a gear linked to the water pump shaft; the tensioner is hydraulic, ensuring effective damping of noise and vibration, while the compact layout guarantees reliability even under the most demanding conditions and RPM levels.

The target was a new class benchmark for size versus performance. Every component was placed with mass centralisation in mind, and the finished engine lands about 1.5 kg under the current class standard.

This is achieved by:
• Main cases die-cast with a special aluminium process that allows extremely thin walls without giving up strength
• Magnesium alloy engine covers, including the cylinder head cover

On the performance side, the 250 4T sits with the best in class. A dual-injection setup — one injector on the throttle body, one on the airbox sleeve — ensures optimal air-fuel mixture management across the entire rev range: crisp response down low, strong and usable power up top. And the top end is where this engine lives.

The rev ceiling is set very high, with high-performance components ensuring reliability:

• Crankshaft journals in dedicated forged steel, spinning on two roller main bearings.
• Forged conrod with a plain bearing to handle the pressures and speeds, keeping inertia, balance and strength where they need to be.
• Box-in-box piston architecture — the same thinking used in Formula 1 engines.

Cooling was developed with CFD analysis to maximise heat exchange and minimise pressure losses. Unlike the 450, it runs a closed-type impeller for better flow in a smaller package, with no external piping to snag or crack. Electric start, a single shared oil supply for engine and gearbox, and an exhaust designed around nothing but power output round out the package.

Gearbox & Clutch
The clutch carries over from the RX 450 4T — seven friction plates, six steel — with a new integral bell housing for the primary driven gears and an updated hydraulic actuation unit. The five-speed box is all-new for this engine, its geometry trimmed for weight and size without giving up strength. Light, compact, quick to engage: a racer's gearbox.

Electronics
For the first time on a Beta four-stroke motocross bike, the electronics come straight from the race team:

•Launch Control, five levels
•Quick Shift
•Traction Control, two levels
•Dual engine mapping (dry, wet)

It's all run from a redesigned control panel integrated into the handlebar pad — easy to reach mid-moto, and with the switches kept off the bar where a crash can't claim them.

Frame & Suspension

The frame was drawn around the new engine, with dedicated geometry and lower tubes that hug the cases for a compact package. Where the RX 450 4T uses a central engine-head mount, the RX 250 4T utilises side-mounted head stays — delivering more torsional stiffness, with the same vertical flex. The result is a new balance between cornering precision and suspension performance, generating greater traction and stability.

The RX 250 4T receives a KYB suspension package that features a 48mm closed-cartridge fork, and a 50mm shock - with setting developed for the lighter and sharper 250 4T.

RX 450 4T - SMARTER AND SMOOTHER

Development of the MY27 RX 450 4T centred on electronics and power delivery.

The big-bore picks up the same Quick Shift and Launch Control as its smaller sibling, the RX 250 4T, while Traction Control has been refined to step in more precisely and progressively. Both engine maps have been recalibrated to dig more out of the engine.

•Launch Control, five levels
•Quick Shift
•Traction Control, two levels
•Dual engine mapping (dry, wet)

It all runs from the same redesigned control panel built into the handlebar pad.

The throttle body gets an update too: a new tapered design that flows more air with less turbulence. The result is crisper throttle response and smoother, more adjustable power on the way out.

RX 250 and 350 Two-Strokes — Two Personalities, Sharpened

Beta's 250 and 350 two-strokes have come in for targeted development from Beta Motorcycles, fine-tuning the handling and performance — each with its own distinct character. The RX 250 2T is the snappy, feisty one: a true race-ready weapon. The 350 is the more progressive all-rounder, versatile and happy pulling longer gears at a relaxed pace with plenty of torque. Two very different personalities, built to suit two different riders.

RX 350 2T
For MY27 the RX 350 2T gets a new piston, designed from scratch to optimise weight and performance. The weight it saves cuts inertia noticeably, sharpening engine response, while new PVD-coated rings reduce friction. These modifications see an increase of around 1.5hp.

RX 250 2T
The final drive moves from 13/50 to 14/51, lengthening the overall ratio. The result is smoother gear progression — most noticeable on fast sections and corner exits, where you want traction and plenty of drive.

Silencer: both engine sizes get updated silencer internals, built to better withstand the punishment of hard motocross use.

Dunlop tyres: like the four-strokes, the two-strokes now run new-generation Dunlop rubber — strong on traction and performance, but lighter than before, and the handling shows it.

Handlebar protection: the bar pad has been redesigned for more rider protection and to bring the two-strokes into line with the four-stroke family and still houses the map-select button.

Across all four RX models:

Chain guide: reinforced to resist mud, sand and impacts, for a more precise and durable drivetrain.
Front sprocket guard: redesigned for superior protection against impacts and debris, and added rider safety — legal under even the strictest competition regulations.
Grips: a softer compound for better comfort and control over a hard moto, embossed with the Beta logo.
Graphics and colours: a new red-and-black livery — aggressive and contemporary, timed to mark the arrival of the long-awaited 250 4T.

The RX Signature

On top of the updates, the following traits that give every RX its character carry over untouched.

Frame: the proven frame geometry of the previous 250-350 two-strokes and 450 four-stroke is retained — already widely rated for its balance of stability, agility and the security it hands the rider. It's an approach that works on the fastest straights and the tightest technical sections alike, with predictable, precise handling that builds confidence from the very first laps. We call it RideAbility.

Aluminium subframe and air filter: the aluminium gives the structure the right stiffness while staying light and soaking up stresses. Filter access stays on the left of the bike — easy, intuitive, and completely tool-free.

KYB suspension: the 48 mm closed-cartridge fork and 50 mm shock carry over with model-specific settings. The updated valving — different on each bike — keeps high sensitivity early in the stroke for agility and bump absorption, without giving up support where it counts: big landings and high-speed sections. The result is a setup that inspires immediate confidence and holds its composure as the pace climbs, letting riders of every level get the most from the bike.

Nissin brakes: floating callipers on Galfer discs — 260 mm front, 240 mm rear — for powerful, controllable stopping.

Handlebar: mounted on silent blocks and raised 5 mm for improved ergonomics and comfort.

Arrival:

250/350 2T, 450 4T - September 2026
250 4T - October 2026

Pricing: To be announced closer to their arrival

INTRODUCING MY27 BETA RX RANGE

Beta's first 250 four-stroke motocross bike arrives alongside sharpened versions of the RX 450 4T and the RX 250 and RX 350 two-strokes.

RX 250 4T

The Engine

RX 450 4T - SMARTER AND SMOOTHER

RX 250 and 350 Two-Strokes — Two Personalities, Sharpened

INTRODUCING MY27 BETA RX RANGE

INTRODUCING MY27 BETA RR X-PRO RANGE

ENDUROGP WORLD CHAMPION MATTHEW PHILLIPS JOINS BETA AUSTRALIA AS BRAND AMBASSADOR

INTRODUCING MY27 BETA RX RANGE

Beta's first 250 four-stroke motocross bike arrives alongside sharpened versions of the RX 450 4T and the RX 250 and RX 350 two-strokes.

RX 250 4T

The Engine

RX 450 4T - SMARTER AND SMOOTHER

RX 250 and 350 Two-Strokes — Two Personalities, Sharpened

INTRODUCING MY27 BETA RX RANGE

INTRODUCING MY27 BETA RR X-PRO RANGE

ENDUROGP WORLD CHAMPION MATTHEW PHILLIPS JOINS BETA AUSTRALIA AS BRAND AMBASSADOR

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