Balancing Lightweight and High Performance: The 93% Efficiency Design Logic of PREETO Mid-Drive Motors

One of the core challenges in eBike design lies in balancing lightweight construction with high performance: make it lighter, and you risk losing power; make it stronger, and weight becomes an issue. PREETO resolves this conflict through structural optimization and material innovation, achieving a rare equilibrium of low weight, strong power, and high efficiency — with an industry-leading 93% energy conversion rate as the defining breakthrough.

Lightweight Design: A Power Core Under 2 kg

Take the P60 model as an example — weighing just 1.95 kg. How is this achieved?

• Material Optimization: The motor housing is made of recyclable aluminum alloy, reducing weight by 30% compared with traditional cast iron while maintaining structural strength. The first-stage transmission gear uses lightweight polymer material that still supports up to 750W peak power transmission, further reducing weight.
• Structural Simplification: Built on a modular platform architecture, the three motor models (P60 / P90 / P110) share core design elements to minimize redundant components. The segmented stator structure increases slot fill rate while eliminating the “bulkiness” of an integral stator, resulting in a more compact and lighter motor body.

High Performance: Enhanced Torque and Power Density

PREETO’s lightweight design does not come at the cost of performance — the key lies in core motor optimization:

• Rotor Topology Optimization: By adjusting the arrangement of permanent magnets, PREETO increases air-gap magnetic density, thus improving torque density. In simple terms, this means more torque within the same volume — 60 Nm for the P60 and 110 Nm for the P110.
• Higher Stator Slot Fill Rate: The segmented stator allows more precise winding and a significantly higher copper fill rate, reducing copper losses. This ensures high-efficiency output even under heavy loads, avoiding wasted power.
• Transmission Efficiency Optimization: PREETO uses DIN 5-grade precision gears with customized profile modifications, minimizing transmission loss. Its three-stage parallel transmission system is 5–8% more efficient than traditional planetary systems, ensuring that more of the motor’s power reaches the rear wheel.

93% Efficiency: A Win-Win for Range and Power

High energy consumption is a common pain point for many eBike users. PREETO’s 93% conversion efficiency means:

• Longer Range at the Same Battery Capacity: With a 720 Wh battery (2.8 kg), range in ECO mode improves by 15–20% compared with conventional motors.
• Lighter Battery for the Same Range: Riders can achieve the same mileage without using a heavier, higher-capacity battery, further reducing the overall vehicle weight.
• Less Heat Generation: Higher efficiency means less energy loss — and less heat. Combined with the stator’s integrated injection-molded cooling design, the motor can maintain high-power output for long durations without overheating.

By achieving this balance of lightweight, power, and efficiency, PREETO delivers an elevated riding experience: agile and responsive yet strong and enduring — without constant charging. This “light, strong, and efficient” equilibrium defines the next level of eBike performance.