350 RX 2-Stroke

THE KINGPIN

0 cc

Engine Displacement

0 Speed

Transmission

36.0 in.

Seat height

300 lbs

Dry Weight

OVERVIEW

350 RX: New engine cases, bore and stroke, as well as a twin-plug head to ignite the special power only a big-bore 2-stroke can provide. The longer crankshaft, combined with the final gearing ratio of 14/47, provides a large amount of torque and overall horsepower that will turn some heads. This 350 motocrosser will thrive in many different track conditions. Clearly in a class of its own!

The 2-stroke range of motocross models also have been refined with updates to the following:

-A new piston for the 350 that saves weight as well as reduces friction, resulting in a 1.5 hp gain.

-Updated final gearing for the 250 to improve starts.

-New muffler that is stronger than the prior model

-Dunlop MX 34 tires

With more torque, increased horsepower, and a refined chassis setup, the 350 RX doesn't just compete—it defines a new standard for what a big-bore two-stroke is capable of achieving.

MODEL HIGHLIGHTS

ENGINE

New Piston

A ground-up piston redesign optimizes weight and reduces inertia, delivering a 1.5 horsepower increase and instantaneous throttle response without sacrificing durability.

EXHAUST

UPGRADE MUFFLER

Both models feature updated internal silencer components to better withstand the stresses of intensive motocross use, maintaining optimal backpressure and avoiding power loss over long motos.

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FEATURES

NISSIN BRAKING SYSTEM

Equipped with a compact, lightweight, motocross-derived Nissin front brake setup that offers immense stopping power with excellent lever modulation.

CHROMOLY STEEL FRAME

Celebrated for its natural flex, the chromoly frame absorbs harsh energy that aluminum frames transfer directly to the rider, providing immediate confidence through high-speed rollers.

SOFTER COMPOUND GRIPS

New, softer grips reduce rider fatigue and arm pump by absorbing trail vibration, allowing you to stay on the gas longer.

FACTORY GRAPHICS KIT

An eye-catching red and black livery conveys an aggressive and contemporary image to accompany the launch of the 250 4-stroke.

HEAVY DUTY CHAIN GUIDE

Features a reinforced structure to withstand mud, rocks, and hard impacts from ruts and logs. A straighter, stronger guide ensures final drive stability, prevents thrown chains, and protects the swingarm.

FLEXFIX HANDLEBAR MOUNTS

Handlebar risers utilize silent-block rubber mounts to isolate the rider's hands from engine vibration.

DUNLOP GEOMAX MX 34 TIRES

Next-generation Dunlop tires significantly improve cornering bite while shedding unsprung weight, allowing the suspension to react faster to acceleration bumps and square-edge chop.

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PHOTO GALLERY

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ENGINE SPECIFICATION

ENGINE TYPE	Beta Built single cylinder, 2-stroke, liquid cooled, with BPV power valve system and counter balancer, electric start.
BORE	78mm
STROKE	73.6mm
DISPLACEMENT	351.7cc
COMPRESSION RATIO	12.45:1
EXHAUST VALVE	Beta Progressive Valve (BPV)
IGNITION	AC-CDI Kokusan
SPARK PLUG	Dual NGK MR7CI8
LUBRICATION	Pre-Mix
CARBURETOR	Keihin PWK 38mm
CLUTCH	Wet diaphram style
TRANSMISSION	5 Speed
FINAL DRIVE	O-ring chain

CHASSIS SPECIFICATION

FRAME	Molybdenum steel / Double Cradle w/ quick air filter access
WHEELBASE	58.2"
SEAT HEIGHT	37.2"
GROUND CLEARANCE	13.4"
FOOTREST HEIGHT	16.6"
DRY WEIGHT	220.5 lbs
FUEL TANK CAPACITY	1.85 US Gallons
FRONT SUSPENSION	48 mm KYB AOS Closed Cartridge with adjustable compression & rebound
REAR SUSPENSION	KYB 50 mm body with adjustable rebound and high/low speed on compression adjustment
FRONT WHEEL TRAVEL	12"
REAR WHEEL TRAVEL	11.8"
FRONT BRAKE	260 mm floating rotor
REAR BRAKE	240 mm rotor
FRONT/REAR RIM	21" (Front) 19" (Rear)
FRONT/REAR TIRE	Dunlop Geomax MX 34

DOWNLOADS

TECH SPECS

*Specifications subject to change without notice. Additional information on all models, including manuals, accessories, and parts books are available online at www.betausa.com under SUPPORT.

MSRP: $10,290.00

6 month Warranty - Parts & Labor

Destination fee $595.00