In the last two years Beta has entered the motocross market with the RX 300 two-stroke, which we have done a test on here, machine while continuing to develop a Beta RX 450 in MXGP. The RX 450 hasn’t been the best kept secret, we have known about it for some time now. We have seen it being raced in MXGP and pictures of what we will likely see go into production started to turn up over six months ago.

Beta could have quite easily just thrown some stiffer suspension in their 430 enduro model but instead they developed a purpose built 450cc machine and we have been left chomping at the bit to get our hands on one.

One, the key word here is one. Beta sent one RX4 50 to Australia as a display model only. As the RX 450 is not in production yet this is a pre-production model that has parts on it that were for display purposes only.

After showing the RX 450 off at the World Supercross in Melbourne the guys at Beta Australia decided to get the bike running and sourced the parts they needed to fire the bike up and then threw together a quick launch to let us throw a leg over the RX 450 for the first time.

 While just about every media company in every country has run a story on the RX 450 we were lucky enough to be some of the first people in the world to get to test the RX 450 for the first time. While this is a pre-production model and the mapping and suspension settings are not yet finalised, this is the bike that will become available in Beta dealers come February 2024.

The Bike

While the RX 450 shares similarities with its 430 enduro cousin, it is a very different bike that is new from the ground up. It has its own purpose built motocross frame that is stiffer than the enduro frame due to the main spar being wider. The subframe on the RX is aluminium with a unique air filter and air filter box that is much higher flowing than any of the enduro models. The fuel tank is a smaller design and while the front plastics are the same the rear section is three pieces to allow you to remove the side number plates and leave the rear guard in place.

The RX 450 comes with KYB suspension both front and rear with a 48mm closed cartridge fork on the front and a 50mm rear monoshock with linkage system on the rear. The fork on the RX has more travel than the enduro models and the rear shock is larger while being valved and sprung both front and rear to suit motocross conditions. The RX has a 21 inch front wheel and a 19 inch rear wheel compared to the 18 inch rear wheel on the enduro models. The RX 450 we tested was fitted with Pirelli Scorpion tyres but we are told that the RX will come off the showroom floor fitted with a set of Maxxis tyres.

The front and rear brakes on the RX are Nissin with the front caliper a smaller more modern design than previously used on Beta Motorcycles and the rear brake reservoir is smaller to make more room for the exhaust. The engine has been specifically designed by the MXGP team to suit the demands of motocross. The gearbox is five speed with dedicated motocross ratio’s while the clutch has been fitted with a diaphragm spring which has three different preload positions.

The crankshaft, countershaft, cylinder, piston and timing system are all unique to the RX 450 engine and so is the 13.5:1 compression ratio. Like the RR enduro models the RX 450 is fitted with a map switch that allows you to select between wet and dry maps and also four levels or traction control. This pre-production model had the map switch mounted on the handlebar but when the model is released in February the map switch will be mounted in the bar pad. We are also told that when the bike is released it will be released with a customised stand and four different throttle pulleys to customise the bikes throttle response.

The First Ride

I test ride motorcycles for a living. I could sit here and complain about the travel and cheap motel rooms but at the end of the day it’s a pretty cool job. I have thirty years of motorcycle experience behind me to get the job but it does set me up for cool experiences like getting to be one of the first media personnel in the world to test ride the brand new Beta RX 450. Being a pre-production model means there will likely be some slight changes to mapping and suspensions settings for the final production model that will be released in February 2024 but for the most part this test on this the model will be the bike that customers can  buy.

The Beta RX 450 really looked the part for our test. The red and blue colours, along with the unique styling, is unlike any other brand. It’s also not a look we are used to seeing in a motocross paddock. But from 2024 onwards we better get used to it because the Beta RX 450 is a very competitive motocross bike that will slot right into the MX1 class very quickly.

The suspension is all KYB front and rear so it’s no surprise to anyone that it works well. The valving is progressive and  forgiving but still stiffens up enough to handle the big jumps around the private facility we got to test it at in Lismore, NSW.

The frame seems to compliment the suspension well. It is absolutely no enduro frame. The frame feels balanced and while the bike did seem to ride high in the front end that is nothing that couldn’t be fixed by adjusting fork height or shock sag.

For this launch we had to share the one bike amongst several riders so there was no time to go adjusting sag or fork height or changing any great deal of settings. It was simply just enjoy the bike the way it was and one thing that I did seem to really like about the RX was the way it sat in ruts. It tipped into ruts really well and sat very well planted in the corners. The bike felt stable and predictable at all times. For Beta’s first ever 450cc motocross bike they seem to have got things going in the right direction.

The engine on the RX 450 is rather rider friendly for a 450 machine. It’s not the fire breather of the 450 bunch but more lends itself to being rider friendly. This is not me saying it’s underpowered. It’s a 450ccc engine so turn the throttle hard enough and the bike will dance but the power is smooth and progressive.

The engine is good at finding traction and getting it to the ground. The bike revs up gradually with no spikes or aggressive power curves that have you death gripping the handlebars. The gearbox ratio’s all work well and have obviously been well tested. The mapping on the pre-production model was slightly off and we had flame out issues at low RPM but this was quickly corrected with a new map being uploaded into the ECU.

Like I said earlier, this is a pre-production model and the mapping is still a work in progress. There will be back and forth testing between Italy and Australia to produce the correct map that will go into the production models that go on sale. One map does not suit every country and every climate around the world so this is common practice for manufacturers.

The brakes on the RX are strong even though I do find the front brake lever to feel rather retro. The clutch has a nice action to it and has three different preload positions in the pressure plate so you can adjust it to have either more or less preload on the clutch pack.

Overall the RX 450 was a smooth bike to ride for our test. The power was easy to get to the ground and the bike was easy to manoeuvre around the track. These two things are always high on my list when it comes to a 450cc motocross machine.

What We Liked

  • Smooth engine, the power is very progressive and user friendly meaning it is an easy 450 to control.
  • Comfortable, the cockpit is very open and free so the bike is easy to move around on and the plastics are smooth so there are no sharp bits of bodywork to get hung up on.
  • Suspension, the KYB suspension always seems to work well no matter what bike it is in. 

What We Didn’t Like

  • Steering, the steering felt a little loose when I first rode the bike and even though I got used to it I would tighten up the steering bearings slightly to make the steering a little tighter.
  • Front brake, this is the same front brake master cylinder Beta use on all their models but it feels outdated to me. It’s the same front brake we saw on CR’s in the 90’s. It works well enough it just feels retro.