By ATN
Summary: YASA has unveiled a prototype in-wheel electric powertrain built around its record-breaking axial flux motor, which recently achieved an unofficial world record of 59kW/kg. The 12.7kg motor delivers up to 750kW per wheel and 350–400kW continuous power, and is paired with a new ultra-high-density dual inverter producing 1500kW at 100kW/kg. This integrated in-wheel system enables major reductions in vehicle mass, removes driveshafts and potentially rear brakes, boosts regenerative energy recovery, and frees up vehicle packaging space. Scaled for a range of performance EVs—not just hypercars—the technology is undergoing development with APC support and promises significant gains in efficiency, performance, and design flexibility.
Key engineering takeaway: A mass-neutral in-wheel powertrain combining ultra-high-density axial flux motors with a next-generation dual inverter enables unprecedented wheel-side power, regenerative capability, and packaging freedom.
Why it matters: By removing heavy driveline components and maximising regen efficiency, OEMs can build lighter, more efficient EVs with greater range and radically improved architectural flexibility—representing a major step beyond current in-wheel motor limitations.
YASA, the global leader in the design and production of axial flux motors, reveals today that the advanced electric motor which recently broke an unofficial world record for power density is the vital component in the company’s latest breakthrough: a state-of-the-art prototype in-wheel electric powertrain system.
“In-wheel motors are the major challenge and opportunity for EVs, but until now, technology has been too heavy, limited in torque and not powerful enough,” said Tim Woolmer, YASA Founder and CTO. “This concept technology breakthrough is compact, powerful and light enough to be positioned inside the wheel of an EV, and it is the world’s first mass-neutral in-wheel motor, enabling up to 750kW (>1000bhp) per wheel. Combined with a new YASA-developed inverter, it results in a fully integrated prototype in-wheel electric vehicle powertrain, which will bring about a step change in weight reduction, performance and efficiency.”
Hitting a staggering 750kW (>1000bhp) peak in testing just a few months ago, YASA’s prototype 12.7kg electric motor set an unofficial electric motor power density world record of 59kW/kg, with the capability to also deliver all-important continuous power of an incredible
350kW-400kW (469bhp-536bhp). Now paired with a next-generation 15kg, 1500kW, 100kW/kg YASA-designed and developed dual inverter – another first, pushing control and power electronics beyond current state-of-the-art (50-70kW/kg) benchmarks – YASA is revealing how its new in-wheel electric powertrain, which is currently undergoing further testing and development, can unleash a whole host of game-changing benefits for future electric vehicles.
Thanks to its incredible regenerative performance, YASA’s new system can dramatically downsize, or even potentially negate, rear brakes, dispensing with discs and driveshafts at the rear of the car, saving ~200kg on components removed with the potential for ~500kg for ground-up designs.
“Thanks to its exceptional regenerative capability, this system has the potential to dramatically downsize rear brakes on an EV – or even remove them entirely in certain architectures. And by capturing a much greater proportion of regenerative braking energy, this technology can also deliver a significant increase in EV range. What’s more, our new in-wheel motor powertrain not only enables significantly lighter, more efficient and higher performance EVs, but also dramatically creates space within the architecture of an EV too, giving car makers unprecedented freedom to redesign and optimise the packaging, aerodynamics and kinematics of their next-generation vehicles,” added Simon Odling, YASA’s Chief of New Technology.
Set to encompass a range of powertrains, from 750kW (>1000bhp) to lower outputs, YASA’s in-wheel technology is not just for ultra-powerful hypercars but for all performance EV applications. Compact, scalable and designed with cost efficiency in mind, a fully functional in-wheel prototype powertrain system has already been undergoing extensive development, with support from the Advanced Propulsion Centre, UK.
“Our new in-wheel electric powertrain is a first for YASA and another example of how we are continuing to push the electrification envelope,” said Joerg Miska, CEO, YASA. “Thanks to the combination of our world record breaking power dense motor and a new YASA-designed and developed inverter, our revolutionary technology addresses the challenges of current existing in-wheel motor systems. It is the gateway to lighter, more efficient and higher performance electric vehicles.”
Further details on the development of the in-wheel powertrain will be shared in 2026.
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