In 2023, Beta’s project to expand the horizons of RideAbility officially entered the motocross market in Europe, first with the RX 300 two-stroke and now with the king of motocross bikes, the RX 450 four-stroke! It is officially the first four-stroke motocross bike built by the Italian manufacturer; for enthusiasts of all riding abilities, this translates into the first chance to ride the Beta MX bike that is based off of the race prototype that competed in the MXGP World Championship for the last three years.
The engine, designed specifically for motocross use, has been developed in close partnership with the Official MXGP Team. The gearbox is five speed, with dedicated ratios, while the clutch (with diaphragm springs, and three adjustable positions) has been designed to withstand the stresses from the engine’s high power output, while offering a light clutch pull at the lever. The weight and dimensions are particularly compact, as the components required for motocross use have been pared down to the minimum. The crankshaft and countershaft are new, as are the cylinder, piston and timing system, allowing a compression ratio of 13.5:1 to be achieved.
The result is excellent engine performance along the entire delivery curve while featuring extended top-end at medium-high engine speeds, those most commonly used on the track. In keeping with the rideability goal which the whole design project was based on, the engine offers excellent torque that provides enjoyable and always controllable progressiveness in all situations.
The RX 450 4T is equipped with two specific engine maps (wet and dry) and four levels of Traction Control (on/dry, off/dry, on/wet, off/wet) to help manage the bike’s significant power in all terrain conditions. The button to select the map and Traction Control is located on the handlebar pad.
Equipped with an electric starter and decompression technology for speedy starts.
Kayaba 48 mm stanchions at the front and 50 mm piston at the rear, with both components completely adjustable, and represent an ideal compromise between rideability and performance, thanks to continuous development on the track. The shock is larger than the one the RR models are equipped with, which provides greater support on landings thanks to greater hydraulic damping, and more consistent performance with demanding use.
The blue anodised wheels are 21” at the front and 19” at the rear, with 90/100-21 and 110/90-19 Maxxis tyres, while the braking system is by Nissin with floating callipers and a 260mm disc on the front and 240mm at the rear. The front brake calliper is a smaller, more modern design.
