First look at the FMF Factory Fatty and Power Core exhaust systems for the big bore two-stroke Beta 350 RX.

We’re big fans of the big bore 350 RX two-stroke from Beta here at Enduro21. It’s one of those bikes we wished we owned and it seems we’re not alone as the 350 RX’s popularity grows around the world.

U.S. exhaust specialists FMF have updated their Factory Fatty header pipe/expansion chamber and Power Core silencer range for the Beta 350 RX. Designed to look good, yeah, sure, FMF say they also improve low-end response and over-rev, with the silencer delivering a “crisper feel” to the big Beta motor.

FMF 2026 350 RX Factory Fatty Pipe

Designed specifically for the Beta 350 RX, this Factory Fatty expansion pipe delivers stronger, smoother power where it matters most. Expect improved low-end response, harder mid-range pull, and improved over-rev without making the bike harder to ride.

Built with hand-rolled and precision-welded construction, this pipe uses lighter 20-gauge steel for performance and reinforced 19-gauge steel in high-impact areas for durability. Finished with a premium plated FMF badge, giving it a true factory look compared to standard stamped logo pipes.

Technical Features

• Designed specifically for Beta 350 RX

• Broader, smoother power delivery

• Improved throttle response

• Stronger mid-range pull

• Reinforced header area for durability

• Premium plated FMF badge

MSRP: $299.99

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FMF 2026 350 RX Powercore 2.1 Silencer

Built specifically for the Beta 350 RX, the FMF PowerCore 2.1 silencer improves throttle response and overall power delivery while keeping weight to a minimum. Designed as a performance replacement for the stock silencer, it delivers a crisper feel and stronger pull without overcomplicating the setup.

This version features a black anodised aluminium canister with stainless mid-pipe for a clean, aggressive look that matches the 350 RX styling.

Technical Features

• Designed specifically for Beta 350 RX

• Improves throttle response and overall power delivery

• Black anodised aluminium canister

• Durable stainless steel mid-pipe

• Lightweight construction

• Race-proven internal core design

• Direct bolt-on replacement

MSRP: $239.99

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FMF 2026 350 RX Titanium Turbinecore 2.1 Spark Arrestor

Designed specifically for the Beta 350 RX, the FMF TurbineCore 2.1 is the world’s best-selling spark arrestor exhaust for a reason. Featuring FMF’s exclusive Turbine Dampening System, it delivers strong, usable power while maintaining U.S. Forest Service approval for legal trail riding.

The straight-through canister design combined with a high-flow stainless steel end cap provides excellent durability and consistent performance without the restriction issues found in insert-style spark arrestors. Built for real-world riding, this silencer performs on both track and trail while offering a clean, factory-level fit on the 350 RX.

Technical Features

• Designed specifically for Beta 350 RX

• Race-tested for smooth, usable power across the RPM range

• U.S. Forest Service approved spark arrestor

• Straight-through design prevents clogging and maintains performance

• Larger diameter aluminium canister for longer packing life

• Crisp, noticeable exhaust tone

• Lighter than stock

• Full aluminium and stainless steel construction

• Optimized to complement FMF pipes but works with stock systems

MSRP: $479.99

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Mufflers for Beta RR models – FMF 2020+ Beta 200/250/300 RR & Race Titanium TurbineCore 2.1 Spark Arrestor Silencer

Built specifically for 2020 and newer Beta 200, 250, and 300 RR and Race two-stroke models, this lightweight titanium TurbineCore 2.1 silencer delivers strong performance while maintaining U.S. Forest Service spark arrestor compliance.

Featuring FMF’s TurbineCore 2.1 system, it improves throttle response, increases exhaust flow, and provides a smoother, freer-revving feel compared to stock. The straight-through spark arrestor design and high-flow stainless steel end cap provide durability and consistent performance without the restriction issues found in insert-style systems.

This is an ideal upgrade for riders who want reduced weight, improved power delivery, and reliable spark arrestor performance for both trail and track use.

Technical Features

• Designed for 2020+ Beta 200/250/300 RR & Race two-stroke models

• Lightweight titanium construction

• FMF TurbineCore 2.1 spark arrestor system

• U.S. Forest Service approved

• Improves throttle response and overall exhaust flow

• Freer-revving, smoother power delivery

• Straight-through design prevents clogging and restriction

• High-flow stainless steel end cap

• Direct bolt-on fitment

• Built in the USA

MSRP: $479.99

 

More information: www.betausa.com/accessories