Wildly overpowered ebike lets you pedal along at highway speeds

We were stunned at the power and sheer audacity of the Stealth B-52 back in 2015 when we first rode it. Ebikes still felt like a pretty new thing at the time, and this Aussie monster threw all questions of street legality out the window to show what these machines could be without regulatory shackles holding them back.

In 2025, ebikes are well and truly embedded in society. Those who try one instantly see why they've become so popular. They're a staple for commuters and delivery folk, and a doorway to an active lifestyle for people that might not otherwise jump on a bike.

And others have picked up on the trail Stealth blazed back in the day – the Chinese-made Sur-Ron Light Bee and Talaria Sting, for example, both sit somewhere in between a dirt bike and an ebike, way lighter than most of the former and dozens of times more powerful than the latter. They've built up a cult following thanks to hilarious performance at crazy-low prices.

Neither of them has pedals, though – but this one does. Stealth is back in 2025 with a considerably juiced-up version of the 4.8-kilowatt (6.4-hp) machine we once called "a mountain bike on steroids... And amphetamines."

The B-52R's hub motor makes up to 8 kW (11 hp), and torque is nearly doubled as well, leaping from 120 to 230 Nm (88.5 to 170 lb-ft). It's more efficient too, losing less energy to noise. "The new model is much quieter than its predecessors," Stealth Bikes Founder John Karambalis tells New Atlas. "With operating sound emissions at around 40 dB." That's about as loud as a fridge, for those who don't speak sound pressure levels.

It's a bit faster than the average fridge, though. Some owners, says Karambalis, are "recording top speeds above 100 km/h (62 mph)." The additional power and torque are messing with the handling a bit – but in the best possible way. "It makes steering a little difficult," he tells us, "because the front wheel rarely touches the ground."

As with the original B-52, Stealth is offering a lifetime warranty on the B-52R's heavy-duty monocoque frame and the 6-speed electromechanical gearshift you can use with the pedals – both made in Australia. "We're confident nobody will be able to break [the chassis]," says Karambalis, throwing down a steaming gauntlet to nutbags worldwide.

We were impressed with the original B-52's 203-mm e-MTB brakes, but Stealth has made a substantial upgrade here, moving to 250-mm motorcycle rotors. The wheels grow too, from 24-inchers with MTB tires to 27.5-inchers running a dirtbike knobby on the rear, a change which Karambalis says has "almost completely eliminated flat tires." Enduro-style suspension offers 180 mm (7.1 in) of travel at the front, 200 mm (7.9 in) at the back.

The battery capacity rises as well – but not super high. The pack holds 2.5 kWh, which Stealth says is enough for a 60-km (37-mile) jaunt between three-hour charges. You probably wouldn't want to go much bigger on the pack, either – the bike weighs in at 70 kg (154 lb). Still significantly lighter than a regular dirt bike, and Stealth tells us it's very easy to handle due to a low center of mass, but the weight is starting to get up there!

As for the handling... Well, there are compromises inherent in the heavy rear hub drive. That's a lot of unsprung weight for the suspension to deal with, and it'll also send the bike's balance rearward. On the other hand, this thing makes so much torque that you'd be looking at a heavy, noisy motorcycle-grade chain or a reasonably heavy-duty belt solution if you relocated the drive to a mid-mount – it'd rip an ebike chain to bits. Stealth has decided to focus its decisions on the needs of unhinged powermongers here rather than riders looking for the safest and most predictable handling. Be warned, it'll be a heck of a handful.

We wouldn't try to get away with riding this thing on the street – Stealth might be the company name, but there's nothing that could camouflage this beefy machine's true intentions or massive hub motor. That's an enormous pity, because I can think of few things that would make kids in back seats on long road trips happier than looking out the window and watching some maniac overtake the family car, pedaling like mad.

This bike is not cheap. At US$8,890, the B-52R is competing against some pretty impressive gasoline dirt bikes for your dollar, and more than twice as expensive as a Sur-Ron. But its near-silent performance, rugged build, next-level power and torque – not to mention the option to actually pedal the thing if you really want to – will set it apart for lunatics that can pay to play.

Electrification opens all sorts of doors to genre-busting vehicles, and Stealth has been choosing the path less trodden for more than a decade now. It's always great to see a wild bike get wilder!

Source: Stealth Bikes

Editor's note: This piece was updated on May 13 to include a note about the hub drive's effect on handling.