2024 Beta RR 390 Review: Specs, Horsepower & Full Buying Guide

If you’re cross-shopping mid-size trail bikes, the 2024 Beta RR 390 deserves a spot near the top of your list. It’s a 385.6cc four-stroke built specifically for trail riders, not racers, and that focus shows up in nearly every part of how it rides.

I’ve spent years testing and writing about off-road bikes, and I’ve dug through the official spec sheets, an in-depth enduro test, and real dealer pricing to put this guide together. By the end, you’ll know the true horsepower, the common problems owners report, whether it’s street legal, and where you can actually buy one right now.

Heading into 2026, the 390 RR remains Beta’s dedicated mid-capacity trailbike, and it still stands mostly alone in that niche. Let’s get into exactly what that means for your money.

What Is the 2024 Beta RR 390?

Direct answer: The 2024 Beta RR 390 is a 385.6cc liquid-cooled four-stroke trail bike with electric start, a 6-speed gearbox, on-demand traction control, and Sachs suspension, built specifically for all-day trail riding rather than motocross or racing.

Beta positions the RR 390 differently than most of its competitors. According to Australasian Dirt Bike Magazine’s hands-on enduro test, it currently stands alone as the only bike in the 300cc to 400cc four-stroke class purpose-built as a dedicated trailbike, rather than a detuned race machine wearing a trail label. That single design choice shapes everything from the seat foam to the power delivery.

For 2024, Beta focused on refinement rather than a full redesign. Key updates include a softer, wider seat, lighter fork tubes for smoother damping, upgraded radiators with better cooling and steering clearance, a stronger front brake line, and a reworked airbox for improved mid-to-high rpm airflow.

2024 Beta RR 390 4-Stroke Specs

The 2024 Beta RR 390 weighs 237 pounds dry, carries a 2.4-gallon fuel tank, and uses a 385.6cc single-cylinder engine paired with a 6-speed transmission and dual-map ignition.

Here’s the full breakdown, verified against Motorcycle.com’s official spec sheet and Beta USA’s factory specifications.

Key Benefits at a Glance

• Trail-tuned power delivery. The engine uses a stepper motor system to smooth out throttle response and prevent bogging in technical terrain.
• Two ignition maps. A rain map tames power on slippery surfaces, while a sun map opens up a sharper throttle curve for dry, grippy trails.
• Push-button traction control. Easy to toggle on the fly without tools or a dealer visit.
• Genuine trail comfort. The redesigned MY24 seat foam and roomy rider triangle are built for long days in the saddle, not short motos.

How Much Horsepower Does a Beta 390 RR Have?

 Beta doesn’t publish an official crank horsepower figure for the 390 RR, but based on dyno testing of the closely related 350 RR-S (36.5 hp at the rear wheel) and 430 RR-S (44.45 hp at the rear wheel), the 390 RR falls in the range of roughly 38 to 40 horsepower at the wheel.

Independent testers consistently describe the 390’s power as strong and torquey for its size. The Australasian Dirt Bike Magazine test team came away feeling the engine’s torque was closer to what you’d expect from the larger 430 or even the 480, minus the extra top-end pull and added weight those bigger engines carry.

That torque-first tuning is intentional. Trail riders spend far more time lugging through technical sections in tall gears than they do pinning the throttle on open fire roads, so Beta prioritized low-end and midrange pull over outright peak horsepower.

Beta RR Horsepower Comparison Table

2024 Beta RR 390 Enduro Test: What Riders Are Saying

Independent testers praise the 2024 Beta RR 390 for its plush, trail-specific suspension and forgiving power, though they note the front fork can dive under hard braking on steep downhills.

According to the full enduro test from Australasian Dirt Bike Magazine, the suspension ranks among the most trail-specific setups the testers have ridden, more forgiving than Beta’s own Racing models while still offering enough support for aggressive riders. You can read their complete 2024 Beta RR 390 enduro test here for the full ride impressions.

Testers did flag a couple of real limitations. The front end can dive somewhat under heavy braking on steep downhill sections, which makes it slightly harder to hold a line into tight corners. They also noted that riders chasing an aggressive race pace should look at Beta’s Race Edition models instead, since the 390 RR is tuned specifically for comfort and control rather than outright speed.

Step-by-Step: How the Traction Control and Riding Modes Work

 Switching between the 390 RR’s rain map, sun map, and traction control takes just a few button presses on the handlebar, with no tools or dealer visit required.

1. Locate the map switch. It’s mounted on the left handlebar within easy thumb reach.
2. Select rain map for wet or loose terrain. This softens power delivery and reduces wheel spin on slick surfaces.
3. Select sun map for dry, grippy trails. This unlocks a sharper, more aggressive throttle response.
4. Press the traction control button to toggle it on or off. Traction control adds an extra layer of rear-wheel grip control, especially useful in loose dirt or bulldust.
5. Adjust on the fly. You can switch maps and traction control mid-ride without stopping, which is genuinely useful when terrain changes quickly.

Is the Beta 390 Street Legal?

The standard 2024 Beta RR 390 is an off-road-only competition model and is not street legal, but Beta also sells a dedicated RR-S 390 variant that comes street legal with lighting, mirrors, and a horn for on-road use in most states.

This is a common point of confusion for buyers. The plain “RR” designation in Beta’s lineup means off-road only, built for trail and enduro riding on private land or designated OHV areas. If road registration matters to you, look specifically for the RR-S badge, which adds the DOT-required equipment needed for street registration.

Registration rules and available equipment do vary by state, so it’s worth confirming exact requirements with your local DMV or a Beta dealer before assuming either version is street legal in your area.

What Are Common Problems With the Beta 390?

The most reported issues with the Beta 390 RR involve overheating in extremely tight, slow-speed terrain, a break-in period needed for the Sachs fork, and a smaller dealer network compared to Japanese or Austrian competitors.

No bike is flawless, and an honest 2024 BETA RR 390 review needs to cover the weak points too.

Common Mistakes When Buying a 2024 Beta RR 390

1. Assuming RR and RR-S are the same bike. Only the RR-S comes street legal, so double check the exact model before buying if road use matters.
2. Skipping a test ride. The power delivery and suspension feel different from Japanese or Austrian competitors, and it’s worth feeling that difference firsthand.
3. Underestimating the break-in period. New owners sometimes assume the fork is defective when it just needs mileage to settle in.
4. Ignoring dealer proximity. Confirm parts and service availability near you, since Beta’s network is smaller than some competitors.
5. Buying based on displacement alone. The 390’s torquey, trail-tuned character is very different from a race-focused 350 or a bigger, heavier 430, so match the bike to your actual riding style.

Tips and Best Practices for New Owners

• Stick to Beta’s recommended maintenance intervals for air filter cleaning, gearbox oil, and spark plugs to keep the engine reliable long term.
• Add a radiator fan accessory if you frequently ride slow, technical single track.
• Give the Sachs fork a proper break-in period before adjusting compression or rebound settings.
• Experiment with both ignition maps and traction control on different terrain to learn how each changes the bike’s feel.
• Budget for a tire swap early if sand or loose terrain makes up most of your riding.

Who Should Buy the 2024 Beta RR 390?

• Trail riders who want a bike built specifically for all-day comfort rather than motocross performance.
• Intermediate riders stepping up from a smaller-displacement machine who want more torque without extra weight.
• Enduro riders who value smooth, predictable power over outright top-end speed.
• Buyers deciding between displacement classes, since the 390 splits the difference between the agile 350 and the heavier, more powerful 430.

Riders chasing motocross tracks or all-out race pace should look at Beta’s Race Edition lineup instead, since the standard RR 390 is purpose-built for trail riding.

Frequently Asked Questions

What are common problems with the Beta 390? The most reported issues are potential overheating during very slow, technical riding, a required break-in period for the Sachs fork, and a smaller dealer network for parts compared to some competitors.

Is the Beta 390 street legal? The standard RR 390 is off-road only. Beta’s RR-S 390 variant adds the lighting, mirrors, and equipment needed for street registration, though exact rules vary by state.

How much horsepower does a Beta 390 RR have? Based on dyno comparisons with the closely related 350 RR-S and 430 RR-S, the 390 RR produces approximately 38 to 40 horsepower at the rear wheel. Beta does not publish an official crank figure.

What’s the MSRP of the 2024 Beta RR 390? The 2024 Beta RR 390 carries a US MSRP of $10,599 plus destination charges, according to official Beta USA pricing.