Beta 350 RX Two-Stroke Motocrosser

Story: Donovan Fourie

The words “two-stroke” hold a very particular place in the minds, hearts and, indeed, souls of motorcycle riders across the board. It’s an ominous place of trepidation that, for road riders, conjures images of 500cc GP legends like Freddie Spencer, Eddie Lawson, Wayne Rainey and Kevin Schwantz bucking and weaving like rodeo pilots, holding on for dear life as their rear tyres failed miserably to cope with the onslaught bearing down on them.

In dirt circles, two-strokes were ubiquitous until the turn of the millennium, when the 450 and 250 thumpers took the reins. The baritone of the four-stroke was accepted on performance grounds, but also on survival instincts – they remain easier to tame and more compliant.

To this day, those motocross pioneers who mastered the 250cc smokers are lauded by all and sundry. Then there were the 500s – a class so terrifying, even to the gods of motocross, that it was never considered the premier class, despite its capacity advantage over the 250s. It was a class for the truly insane.

With such an ominous history, it’s little wonder that we recruited a band of top-notch motocross riders to swing a leg over the new Beta 350 RX rather than daring to do so ourselves. The ever-calm James Lottering took a break from his duties at Suter, madman Enrico Narbonese stepped up to the plate, and the wealth of knowledge that is Ryan Hunt put his hat into the ring.

With that, TerraTopia – fresh from its victorious MX GP round – stood before us, while Russell Campbell and his team prepped the RX.

Beta started life in South Africa as a small upstart hoping to make a dent in the dominance of the Austrians and Japanese. Two decades later, we are seeing more and more light-red bikes dotted along starting lines throughout the dirt world.

And now, here we are – a two-stroke 350cc MX bike ready to start another chapter in its evolving story.

The highlights read thus: The motor displaces 351.7cc of boom, cooled by liquid and fuelled by premix via a Keihin 38mm carburettor. There are no claimed horsepower or torque figures, which normally means they are not good; however, we suspect this has more to do with not wanting to intimidate potential customers.

To put it frankly – if those 30-year-old two-stroke 250 MXers were feared, how terrifying would a 350 with the benefit of the latest modern technology be? Luckily, we had three brave souls to find out.

The RX looks good, as anything designed by the Italians should. This one was further kitted out in special Russell Campbell livery for an added touch of local flavour.

The seat pops off with one touch of a button – a party trick of Beta. The air filter it reveals also comes off without any need for tools or mechanical mastery.

The electric start begins a melodic ding-ding two-stroke chime, although one with a notably deeper tone than your average smoker. On the course, this deeper note continues, denoting something on the gruffier side of the usual 50c coin rattling in a Quality Street tin.

Our brave riders lapped with poise and grace, looking far more in control than we expected – bereft of the manic wheelspin, hanging-on-for-dear-life and painful near-deaths that usually follow a two-stroke of this calibre. What has happened? Is this bike a dud? Were the riders really trying?

Some analysis upon their return to the pits gave us clarity – they were indeed trying, and this motorcycle is indeed fast, but deceptively so. It transfers power in a manner that favours linear delivery over the sudden power bands for which previous smokers were famous. This linear power meant the rear tyre was never truly surprised and could simply get on with the job of being a tyre.

More so, the RX has two rider modes – one more aggressive and one that tames the power, especially useful when riding in mud or lower-grip conditions. Traditionally, rider modes are controlled by fuel injection, which alters the fuel flowing into the motor electronically. The RX, however, does not have the luxury of electronic fuel injection and has to make do with a conventional carburettor. This sounds suspiciously like witchcraft, and before we could erect a stake for a good burning, we discovered that the maps work by altering the ignition timing via the CDI unit. It still sounds like sorcery, but we will let it slide this time.

While the RX does not throw out fireballs of power in narrow bands of the rev range, it instead offers steady grunt that makes it far easier to ride, delivering a deceptive speed that saw the riders often completely over-jumping obstacles.

This was aided by a machine that “felt like a 125”. Being a two-stroke, its engine is made up of a piston connected to a crank assembly – and that’s everything. No silly extra chains, camshafts, valve springs or any of that nonsense. It saves a lot of metal, allowing a dry weight of 100 kg.

What’s more, there are far fewer metal bits spinning, offering an even lighter feel than the quoted weight suggests.

It also means less to maintain and less complicated stuff to strip when the time comes. Replacing a piston can be done with a simple toolbox and a meagre amount of mechanical know-how.

The suspension is from KYB and is fully adjustable – something the riders took to heart. After a few clicks here and there, everyone was all smiles.

The riders seemed genuinely happy as the day progressed. Their day-to-day racers are bigger four-strokes, so it took them some time to adjust to the lighter smoker. Once they had settled, they seemed to genuinely enjoy the RX.

Traditional racing classes cater for 250 and 450 machines, mostly in the four-stroke realm. The RX might find a home in the Open Class or the Vet Class, where capacity has little restriction. Surprisingly, it is also suited to riders of a more casual demeanour – something not often said about big two-strokes. But this is the modern world in which we live, where even the mighty smokers have found their manners.