YASA’s proprietary axial flux motors are smaller and lighter than their competitors due to more efficient use of key magnetic and structural materials. The YASA (Yokeless And Segmented Armature) motor topology also significantly reduces manufacturing complexity, making the motors ideally suited to automated volume production. This powerful combination enables YASA to produce motors with exceptionally high power and torque density that, in volume, cost less than competing products.

YASA has built on the work undertaken by founder Dr Tim Woolmer during his DPhil at Oxford University and now has numerous patents and patent applications covering the key subsystems (rotors and stator) of its unique axial flux "pancake style" motor.  The patents  cover the critical aspects of axial flux motor manufacture as well as design and include thermal, structural, magnetic and manufacturing techniques.

Manufacturing Processes

The Yokeless And Segmented Armature topology has enabled YASA to develop simplified motor manufacturing techniques that are very repeatable and cost-effective. The manufacturing method is highly scalable and suited to all levels of customer demand from small batches through to serial production.

Manufacturing takes place in YASA's own ISO9001:2008 accredited facilities.



Custom Motors


Based on the principles of the YASA topology, YASA Motors is capable of producing the smallest volume, lightest weight motors in their class. Standard products are suitable for many applications and our skilled and widely experienced engineering teams have the capability to provide custom solutions from the prototype stage all the way through to high volume production.

The YASA 750, YASA P400 Series and YASA 400 axial flux motors achieve power densities of up to 10kW/kg and torque densities which are significantly better than the nearest competitive motor topology. High power densities are achieved at relatively low speeds (2000-9000rpm) which make the motor ideally suited for hybrid and generation markets.

As well as our standard products, YASA creates custom products for volume manufacture which meet a specific torque, power and speed requirement at the highest operating efficiency at the lowest possible unit production cost.


Test Capability

YASA operates three dynamometer test rigs that enable testing up to 10,000rpm, 800Nm and 400kW.

These bespoke dynamometers are run with in-house developed software enabling a wide range of thermal and performance tests to be undertaken. A wide range of customer drive cycles can be tested with high dynamic and continuous loads. Please contact YASA for further information.

Test rigs