Dirt Bikes

2026 Beta 350 RX Technical Overview

Features and specifications of Beta’s largest-displacement two-stroke motocross bike for 2026.

May 18, 2026

Beta continually impresses motorcycling enthusiasts with new and exotic models. For 2026, the Italian manufacturer debuts the 350 RX: a purpose-built big-bore two-stroke motocross machine. Replacing the 300 RX, which was available from 2021–2025, the 350 RX is Beta’s two-stroke answer to open class and 450cc four-stroke competition. Now featuring 250 RX and 350 RX two-strokes in addition to the 450 RX four-stroke, Beta’s RX motocross lineup is more diverse than ever. Read on to learn about Beta’s all-new 350 RX model, which arrives with an MSRP of $10,290.

Brand new machines are rare in this 250cc and 450cc day and age of dirt bikes, but Beta breaks the mold with its 350 RX two-stroke motocrosser. Glistening in California sunshine, red, white, and blue hues are absolutely vibrant.Jeff Allen

A 78.0mm bore and 73.6mm stroke yields a displacement of 352cc. Compared to the 300 RX, which featured a square 72.0mm bore and 72.0mm stroke, the 350 RX’s personality is robust yet rideable. Carburetors are alive and well in 2026, and intake is supplied via a Keihin PWK 38mm carburetor and Moto Tassinari VForce4 reed valve assembly.Jeff Allen

Beta’s carbureted liquid-cooled two-stroke 352cc single-cylinder engine design features a Beta Progressive Valve (BPV) adjustable power valve system and counterbalancer. Behind the petcock lies a dual spark plug cylinder head.Jeff Allen

The 350 RX comes standard with electric starting, though a backup kickstarter kit is sold as an option. BPV is externally adjusted by the gold screw, located just beneath the water pump.Jeff Allen

A nickel-plated pipe will withstand hours of abuse, and our test unit was already broken-in when it reached our hands. Red radiator louvers protect even the lowest points.Jeff Allen

A frame brace that doubles as a skid plate mount is located beneath the exhaust spigot.Jeff Allen

The 350 RX’s silencer emits a deep, open-class tone. It’s more minimalistic in design compared to the 300 RX predecessor’s, and both mounting bolts can be easily checked with one’s favorite T-handle.Jeff Allen

Radiator shrouds are distinctly Italian, featuring both red and white plastics. Two radiator braces help keep everything aligned, while the translucent 1.5-gallon fuel tank allows for quick and easy level checks.Jeff Allen

Glue-on Beta-branded grips are ready with two locations for meticulous mechanics to install safety wire. Controls are simple with a red engine stop button on the left…Jeff Allen

And blue engine start button on the right. A Domino throttle assembly ensures smooth operation. In all black trim lies the Nissin front brake master cylinder. Beta utilizes Brembo components for hydraulic clutch actuation and Nissin assemblies for front and rear brakes.Jeff Allen

No-tools air filter access and an intuitive air filter design are Beta trademarks. The aluminum subframe and reinforced frame come directly through input from Beta race teams.Jeff Allen

Quality KYB suspension components and black billet aluminum triple clamps grace the 350 RX.Beta

Red accents on the fork caps contrast nicely with the black triple clamps. Three fixed handlebar mounting locations allow for rider triangle customization. Xtrig FlexFix bar mounts come standard as well in 2026.Beta

KYB 50mm shock assembly complements the KYB Air-Oil Separate (AOS) 48mm closed-cartridge coil-spring fork. Shock spring preload is adjustable via two steel lock rings. Adjusters on the shock body are for low-speed compression damping (silver flat-blade screw) and high-speed compression damping (17mm blue nut).Jeff Allen

Shock rebound damping adjustment is found on the clevis and readily accessible with the bike on or off a stand.Jeff Allen

Beta’s two-tone black and raw aluminum swingarm stands out on each and every RX model. Red frame guards, chain guide, and axle blocks contrast with the blue Excel Takasago rims and black spokes. Rear brake rotor size is 240mm.Jeff Allen

14/47 gearing and a 120/80-19 rear tire put every ounce of power to the ground. Our testbike came equipped with Bridgestone Battlecross X31 sneakers, and the tire manufacturer is well-represented on Beta USA’s factory racebikes too.Jeff Allen

Bridgestone Battlecross X31 front tire in 80/100-21 sizing.Jeff Allen

Galfer 260mm rotor, Nissin hydraulics, and a steel-braided line ensure accurate braking up front. Beta’s fork guards are uniquely shaped at their lowest point.Jeff Allen

Galfer supplies the 240mm rear rotor as well, and our test unit had a serious brake dragger at the helm before arrival! Beta’s red axle blocks can be flipped 180 degrees depending on chain length and gearing combination.Jeff Allen

Steel footpegs replace the aluminum units found on the prior-generation 300 RX.Jeff Allen

Sharp lines and Italian styling adorn the 350 RX. Beta is one of the only manufacturers in recent memory to run a vent in its front number plates.Jeff Allen

New radiator shrouds are more exposed in the midsection than years prior. Beta is also one of the only brands to run a radiator cap on the left side.Jeff Allen

Italy is on to something, as the 350 RX is a hit! It’s available now and one of the most unique new models offered by any manufacturer in quite some time. Beta continues to provide some of the best support for new owners in the industry, and a Build Your Own Beta (BYOB) program allows customers to personalize their ride before taking ownership.Jeff Allen

2026 Beta 350 RX Specs

MSRP:	$10,290
Engine:	Liquid-cooled, 2-stroke single-cylinder
Displacement:	352cc
Bore x Stroke:	78.0 x 73.6mm
Compression Ratio:	12.5:1
Transmission/Final Drive:	5-speed/chain
Dirt Rider Measured Horsepower:	46.2 hp @ 7800 rpm
Dirt Rider Measured Torque:	32.4 lb.-ft. @ 6700 rpm
Fuel System:	Keihin PWK 38mm carburetor
Clutch:	Wet, multiplate diaphragm style; hydraulic actuation
Frame:	Double-cradle chromoly steel
Front Suspension:	KYB Air-Oil Separate (AOS) 48mm closed-cartridge coil-spring fork, compression and rebound damping adjustable; 12.0 in. travel
Rear Suspension:	KYB shock, spring preload, high/low-speed compression damping, and rebound damping adjustable; 11.8 in. travel
Front Brake:	Nissin 2-piston caliper, 260mm floating disc
Rear Brake:	Nissin 1-piston caliper, 240mm disc
Tires, Front/Rear:	Dunlop Geomax MX34; 80/100-21 / 120/80-19
Rake/Trail:	N/A
Wheelbase:	58.7 in.
Ground Clearance:	13.4 in.
Dirt Rider Measured Seat Height:	38.1 in.
Fuel Capacity:	1.5 gal.
Dirt Rider Measured Wet Weight:	235 lb.
Availability:	Now
Contact:	betausa.com