Radian EXR vs Stark Varg: battery swap and on-board charger?
Dutch EXR with removable battery versus Stark Varg – who sets the benchmark?
The Radian EXR is a new electric enduro bike from the Netherlands with a removable battery in under 30 seconds, 70 PS and 1,060 Nm of torque. Market launch Q4 2027 from 14,450 Euro. Is it essentially a Stark Varg with additional features?
When I saw the Radian EXR for the first time, my first thought was: "This is basically a Stark Varg, only with a replaceable battery and on-board charger." I took a close look at the data – the thesis partly holds up, but not quite as it sounds at first glance.
What Radian is showing
The Dutch company Radian is presenting the EXR, an electric enduro bike that claims to be the world's first truly competitive electric enduro motorcycle. On paper, that is a serious statement:
- 70 PS / 52 kW peak power
- 1,060 Nm of torque at the rear wheel
- 14,000 rpm maximum speed
- 336 V system voltage, IPM motor with carbon-sleeve rotor
- 125 kg target weight with Endurance battery pack
- Road approval included from the factory
- KYB suspension, Brembo brakes, Haan Wheels, Excel A60 rims in the Founders Edition
- Aluminium frame that also serves as a heat sink
- Configurable via app (Custom / Enduro / Hard Enduro / MX / SM, 10–70 PS)
Three years of development, EU funding through the EFRO-Ost programme, cooperation with the University of Twente and the Fraunhofer Innovation Platform for Advanced Manufacturing. The team comes from the Electric Superbike Twente racing project, which won the MotoE championship in its debut season in 2018. So it is not a garage project.
Putting my thesis to the test
Let's look at it directly – Radian EXR versus Stark Varg MX 1.2 Alpha:
What is correct about my thesis: The battery swap in under 30 seconds is genuinely the real differentiator. The InfiniPack system consists of two 4.3 kWh modules weighing 22 kg each, which can be removed from the side without tools. At the same time, the mobile InfiniDock station (3.3 kW, 90 minutes from 20 to 80 percent) charges the second pair of batteries. While you are riding, the next set is ready. Stark Future has nothing comparable so far – the Varg battery is permanently installed.
What is not correct: The on-board charger is explicitly labelled on the Radian website as "Not yet available – future accessory". As standard, the EXR comes with an external 3.3 kW charger and the InfiniDock station. On the Stark, the charger is housed in the bike stand – not "in the bike" either, but practically just as ready to use. Here, the Stark Varg is currently actually better placed because the setup works from the factory rather than having to wait for announced accessories.
And an important point regarding classification: the direct comparison bike is actually the Stark Varg EX, the road-legal enduro variant. The Radian EXR was developed from the outset as an enduro with homologation, not as a pure MX machine.
Where the Radian is genuinely new
If I had to reduce it to one point: InfiniPack. The battery itself is not spectacular – 8.6 kWh, IP67-equivalent, 44 kg in total – but the concept is. Stark, Cake, Sur-Ron, Talaria: they all currently rely on "put the battery in, charge it fully, done". Radian says: in racing, waiting is not an option. You need to be able to refuel the bike like a carburetted race bike. And they apparently manage that.
There are also a few smart details: the Smart Storage system as 7-litre storage space for tools, spare parts and provisions, with open 3D-print files for your own modules. An integrated timing system (no more card on the handlebars). Reverse gear at the press of a button for trailers and the garage. OTA updates. And in the future, an InfiniPack Sprint with 5.8 kWh, which brings the total weight down to 113 kg.
What makes me sceptical
Q4 2027. That is more than 1.5 years away. During that time, Stark Future can further develop its Varg EX – the company closed 2025 with record growth and profitability and is industrially far more solid than Radian. The InfiniPack patent alone does not prevent Stark, Cake or a Chinese manufacturer from following up with their own replaceable battery.
Pre-order for 99 Euro – you can do that, but with a delivery date in 18 months or more, it is more of a reservation than a commitment. The first batch goes to the Netherlands, Belgium and Germany, with the rest of Europe to follow.
Production numbers unknown. Radian has not publicly communicated production volumes. The first editions are regionally limited – meaning: small quantities, major hype, then we will see whether it holds up industrially.
Conclusion
My original thesis was not wrong, but it sells the Radian EXR short. It is not simply "a Stark Varg with a replaceable battery" – it is a bike that beats the Stark Varg in precisely the one area where previous electric enduro bikes have failed: range in racing use. InfiniPack plus InfiniDock is the first credible answer to the question of how to get through a race day electrically. What the Radian really has to prove: that it actually delivers in Q4 2027. Until then, the Stark Varg remains the benchmark in production-oriented electric off-road riding – but anyone heading to hard enduro race days should keep a very close eye on Radian.
