Dirt Bikes

2024 Beta 450 RX Technical Information

Features and specifications of Beta’s 450 four-stroke motocross bike.

May 26, 2024

Beta has been building motorcycles for more than 115 years out of Florence, Italy, and the 2024 Beta 450 RX is officially the brand’s first four-stroke motocross bike. While the 2021 Beta 300 RX two-stroke provided entry into the modern motocross market, the 450 RX design is the manufacturer’s first to be completely new from the ground up. Featuring a five-speed transmission, separate compartments for both engine and transmission oils, KYB Air-Oil Separate (AOS) 48mm closed-cartridge coil-spring fork, KYB 50mm shock, along with unrivaled Italian styling, the 450 RX is one unique steed. Read on to learn more about the all-new machine and view an extremely detailed photo gallery.

Behold: the 2024 Beta 450 RX. Rideability remains Beta’s tagline, and the 450 RX intends to bring this mantra to motocross.Jeff Allen

The fuel-injected liquid-cooled DOHC four-stroke 449cc engine features a rather unique bore and stroke of 97.0mm x 60.8mm. This same stroke is also used on Beta’s 430 RR, 430 RR Race Edition, 480 RR, and 480 RR Race Edition off-road models. A compression ratio of 13.4:1 is one of the most aggressive from the Italian brand.Jeff Allen

The striking stock exhaust immediately catches one’s eye, but there’s more to the story. A diaphragm-style clutch with three adjustment options allows riders to customize feel, and red accents can be found throughout the bike.Jeff Allen

Yes, the head pipe will immediately blue up nicely. This was a brand-new unit, with only minutes of run time on a bike stand. Also, note the built-in skid plate mount that connects the lower frame rails, which is great for those who wish to add one at a later time.Jeff Allen

An artfully crafted resonance chamber comes standard. HGS builds this exhaust for Beta and it’s top of the line.Jeff Allen

The beautiful Beta factory muffler produces a pleasant tone in stock trim, unlike many 450cc competitors…Jeff Allen

And dual tabs ensure it’s not going anywhere!Jeff Allen

No tools needed for air filter access. Another plus is that a quality Twin Air filter comes standard.Jeff Allen

A 2.2-bar radiator cap can be found on the left side, and overheating was never a concern on our test day. The radiator shroud design allows proper access as well. Kudos, Beta.Jeff Allen

Beta takes a different approach to the location of the engine map and traction control options, positioning it in the handlebar pad. Two engine maps come standard, and traction control can be enabled or disabled based on rider preference.Jeff Allen

Blue electric start button on the right, next to the Domino throttle. Equipped with optional cams to adjust response, new owners have a variety of options to test. From slowest to fastest cams, Beta includes the following reels: blue, gray, brown, orange, and black.Jeff Allen

Kill switch on the left, near the glue-on grip embossed with the Beta logo. New owners would be wise to install safety wire, straightaway, to keep both grips from twisting or spinning.Jeff Allen

Inside the black clutch cover lies a separate transmission oil compartment and three optional engagement settings within the diaphragm-style clutch. The clutch-side red fill cap is best serviced with Liqui Moly lubricants, as described on page 13 of this model’s owner’s manual.Jeff Allen

Red anodized engine oil fill plug on the left, ignition cover side. Separate oil compartments is a rarity on modern 450cc motocrossers, though appreciated. Each side drinks 750 milliliters to fill up after “normal maintenance work” (i.e., an oil and oil filter change), 800 milliliter after “complete engine review” (as in a full rebuild).Jeff Allen

Related: 2023 Beta 300 RX Review

Red anodized oil filter cover and filter can be found down low, on the ignition cover side—10 Nm is all it takes to keep everything in place.Jeff Allen

Engine oil sight glass is easy to keep tabs on, while the clutch side for transmission oil uses a simple check bolt design.Jeff Allen

The KYB Air-Oil Separate (AOS) 48mm closed-cartridge coil-spring fork caps are even anodized Beta red. Standard fork settings (from completely closed): 10 clicks out on compression damping, 14 clicks out on rebound damping.Jeff Allen

Flush fork height was what we encountered on our test day, though this can be a tuning element for many versed riders and racers. The black billet aluminum triple clamps look sharp, and multiple handlebar position options provide plenty of adjustment.Jeff Allen

The KYB 50mm shock differs from the C46 unit found on many other Beta models such as the 300 RX motocrosser and Race Edition off-roaders, indicating the brand went all-in to optimize the 450 RX chassis and handling character.Jeff Allen

The blue 17mm nut is the high-speed compression damping adjuster. Low-speed compression damping is the flat-blade screwdriver adjuster located within the blue high-speed dial. Clockwise is stiffer, counterclockwise is softer. Standard shock settings (from completely closed): 2 turns out on high-speed compression, 26 clicks out on low-speed compression, and 16 clicks out on rebound.Jeff Allen

Silver shock spring comes with a 54 Nm rating, complementing the 4.9 Nm fork springs.Jeff Allen

If you know, you know. Brembo manufactures some of the best hydraulic clutches in the game.Jeff Allen

Paired with Beta-spec’d Nissin braking components and steel-braided brake lines, you have serious quality and control at your fingertips.Jeff Allen

A Nissin dual-piston front caliper, Galfer 260mm front rotor, and steel-braided line ensure accurate braking. Front axle torques to 50 Nm.Jeff Allen

Nissin single-piston caliper, Galfer 240mm rear rotor, and steel-braided line out back too.Jeff Allen

Black swingarm against the red axle blocks really stands out. Rear axle torques to 130 Nm.Jeff Allen

Quality D.I.D chain, red chain guide, and dual-material rear sprocket all come standard. A Maxxis Maxxcross MX-ST rear tire in 110/90-19 sizing is OE spec.Jeff Allen

A genuine Excel Takasago blue front rim, black spokes, and fresh Maxxis Maxxcross MX-ST tire up front.Jeff Allen

Black spokes paired with billet aluminum hubs really stand out! Both front and rear wheels come equipped with a two-cross spoke lace pattern.Jeff Allen

Anodized red aluminum inner, black steel outer, and precision routering to expose the natural aluminum accents of the rear sprocket. Torx sprocket bolts lock it down. The 450 RX comes equipped with a standard 520 chain and final drive of 13/50.Jeff Allen

All-in-one composite chain guide keeps everything in line on the drive side.Jeff Allen

Black anodized aluminum footpegs with steel pins come standard and are fairly wide by OE standards. Beta Factory insignias are found throughout. Even the rear brake pedal is accentuated in black, just in camera view.Jeff Allen

A blue Blackbird Racing seat cover matches the color ensemble perfectly and the convenience of push-button attachment is currently unrivaled by any motocross competitors. My only complaint is the new 450 RX seat base does not correlate to any other existing Beta models regarding fitment: Aftermarket suppliers will need time to catch up for the 450 RX specifically…Jeff Allen

A translucent 1.8-gallon gas tank is 450 RX-specific and, ergonomically, quite thin. Most other Beta models feature 2.4- or 2.5-gallon specifications, even the 300 RX motocrosser.Jeff Allen

The red, white, and blue radiator shroud graphics match the motif perfectly, and the cockpit is slimmest in the full-size Beta dirt bike lineup. Considering the aggressive styling, everything has a purpose. Even the white radiator louvers extend low enough to protect the lower reservoirs.Jeff Allen

Front fender and number plate styling, straight outta Italy.Jeff Allen

Even the front fender decal features Beta branding.Jeff Allen

At $10,999 you buy quite a bit of bike. If you’re looking for a ride that turns heads, look no further than the 2024 Beta 450 RX.Jeff Allen

2024 Beta 450 RX Specs

MSRP:	$10,999
Engine:	DOHC, liquid-cooled single-cylinder; 4 valves/cyl.
Displacement:	449cc
Bore x Stroke:	97.0 x 60.8mm
Compression Ratio:	13.4:1
Transmission/Final Drive:	5-speed/chain
Fuel System:	EFI w/ 46mm throttle body
Clutch:	Wet, multiplate diaphragm; 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:	Maxxis Maxxcross MX-ST; 80/100-21 / 120/80-19
Rake/Trail:	N/A
Wheelbase:	58.4 in.
Ground Clearance:	13.0 in.
Claimed Seat Height:	37.2 in.
Fuel Capacity:	1.8 gal.
Claimed Wet Weight (Without Fuel):	229 lb.
Availability:	Now
Contact:	betausa.com