2027 Beta RX 350 Review

The Beta RX 350 is unlike any other dirt bike on the market. With a 351.7cc engine, it sits at the top of the totem pole among modern, big-bore two-strokes and brings back the glory days when open-class racers ruled the roost. It’s one of the most unique bikes on the market and doesn’t play by anyone else’s rules. The RX 350 is a relatively new model from Beta, first released in 2025 as a 2026 model, replacing the RX 300.

Beta is no stranger to the two-stroke game. The Italian brand offers five two-strokes in its lineup, including two motocross-specific models—the RX 250 and RX 350. Beta offers its RR off-road two-strokes in 125, 200, 250 and 300cc displacements, but no 350. However, it does offer a 350 four-stroke in its off-road RR lineup.

The RX 350 isn’t just a big-bore version of the previous RX 300. The engine is specifically designed, featuring a more efficient dual-spark-plug system and a true 351.7cc displacement, delivering 45-plus horsepower. Beta says it has 1.5 more horsepower thanks to a newly designed piston. The engine is counterbalanced, features its tunable Beta Progressive Valve (BPV) exhaust power-valve system, and uses a Keihin PWK 38mm carburetor for fueling. No EFI, which should please many old-school two-stroke diehards. It holds 1.85 gallons of premix fuel.

The muffler has been redesigned for more durability.

The RX 350 also includes modern features such as a hydraulically operated wet diaphragm-style clutch, electric start and two ride modes, accessed via a map switch centered on the handlebar pad. The aggressive map is shown as a sun on the map switch, and the smoother mode displays a cloud with raindrops.

A powder-coated black steel frame pairs with the black swingarm, engine cases and rims. The Beta’s chromoly-steel frame is fitted with fully adjustable suspension, including top-tier KYB Air-Oil-Separate (AOS) forks and a 50mm KYB rear shock, with Dunlop MX34 tires putting power to the ground. It’s fitted with a 19-inch rear wheel and uses a Nissin disc brake up front (260mm) and in the rear (240mm).

It also features vibration-damping bar mounts, a push-button seat release and toolless access to the air filter. Beta claims the RX 350 has a dry weight of 220.5 pounds, the same as the RX 250. Beta says the RX 250F four-stroke model is three pounds heavier.

The 2027 RX 350 retails for $10,290, the same price as in 2026.

On paper, this bike is unlike anything else, and the ride lives up to that. Right away, you can feel how torquey and snappy this engine is, and it’s clear this isn’t just a big-bore 250. Having ridden the RX 300, you can tell this feels beefier. The jetting is spot-on, and it feels and sounds exactly how you’d want a big 350 two-stroke to sound, if not a little better.

You can see some of the plastic vibrating at idle, which was a little worrisome, but once you get on track, it’s not all that noticeable, especially when you’re in the meat of the power. Throttling is spot on, and you feel the power come rushing as soon as you crack the throttle; however, it does its best work in the middle of the powerband. Second and third gears are this bike’s sweet spot, and the power carries high into the rpm. You have to shift a lot to keep it in its happy place, from the mid- to top-power zone.

The sun map offers a lot of punch right as you get to the meat of the power. As the track dried out and revealed slicker, hard-pack sections, I preferred the rain map. The smoother power curve helps the bike hook up better on slick ground and makes it more rideable, which you will appreciate near the end of a long moto.

Suspension is good all around; the KYB AOS fork is top-notch. For my 180-plus weight, the fork has good small-bump comfort, but it starts to feel a bit soft when you really push it and hit the jumps. Stiffening up the compression made things better when the pace picked up. The rear end is a bit soft, too, so I made a few tweaks. The shock has lots of adjustments, including high- and low-speed compression damping. I also adjusted sag to give the chassis better hold-up, improving feel in faster sections.

The bike feels very light. With less engine-braking feel than a four-stroke, the chassis feels extremely free and nimble. It’s a rather tall motorcycle with a 37.2-inch seat height.

The grips on the 350 are uber-comfortable. The soft-compound handgrips are the best stock grips I’ve felt in a long time. Paired with the elastmoner-damped bar mounts, vibration is a non-factor.

The brakes are more than capable of slowing this beast down, and the hydraulic clutch feels light with good modulation and feel; I never felt a hint of fading on this sweltering hot summer day in Southern California.

While the RX 350 is super fun and unique, it’s not perfect. The Beta has a 14/47t final drive, but I think a 48t rear sprocket would be better, since it would help it spool up faster out of tight, rutted turns. It has tons of torque, which is great, but I’d like a little more snap when you first open the throttle. As it is, you need a little clutch work to wake up the engine when trying to carry second or third gears out of the turns. Plus, with the stock gearing, I’m sure the 350 can hit 90 mph in the straights, which is a little overkill. Again, a larger rear sprocket might be the simple answer, or a larger countershaft sprocket, or some kind of combination of both. If this were my bike, I’d experiment with gearing. Beta markets the RX 350 as a motocross bike that can also be ridden recreationally with vets in mind, who like to rail the outside lines at a lower rpm, which might explain the “universal” stock gearing and trying to appease both types of riders.

Overall, this Beta is a ton of fun to ride because it doesn’t fit the mold. It’s a modern big-bore two-stroke with personality that reminds us of those classic 500cc monsters but is much easier to manage. With newcomers like the Kawasaki KX327 soon entering the ring, the Beta RX 350 finds itself at the center of a modern-day battle for two-stroke supremacy.CN

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2027 Beta RX 350 Specifications

Click here to read the 2027 Beta RX 350 Quick Spin in the Cycle News Digital Edition Magazine.