Kollmorgen / NovaCruz / Voloci – New-in-Box (Early 2000s Production)

Quick Summary (Non-Technical)

This is a high-quality industrial brushless DC motor originally designed for the Voloci lightweight electric motorbike. It runs on common 36–48V battery systems and is built to deliver strong torque at low and moderate speeds, making it well suited for electric bikes, small EVs, robotics, or custom mechanical projects.

These motors are frameless, meaning they are intended to be built into your own housing, wheel, or gearbox. This makes them ideal for custom designs where space, weight, or integration flexibility matters.

Smooth, quiet brushless operation
Designed for traction rather than very high RPM
Works with standard sensorless BLDC motor controllers
New-in-box, never used (manufactured 2001–2003)

Important:
This listing is for the motor only. No shaft, bearings, housing, or controller are included.

Technical Specifications (For Engineers & EV Builders)

Electrical & Performance

Motor type: 3-phase brushless DC (BLDC), sensorless
Connection: Wye (Y)
Rated voltage: 36 VDC (commonly used in 36–48V systems)
Rated speed: ~1200 RPM
Approx. no-load speed: ~1720 RPM @ 36V
Rated torque: ~1750 oz-in (≈ 12.0 Nm)
Rated output power: ~1.55 kW
Peak electromagnetic efficiency: ~83%
Rated RMS current: ~68 A
Peak current: ~85–90 A (short duration)

Performance curves show a broad constant-torque region up to ~1200 RPM, followed by a linear torque drop at higher speed, consistent with traction-optimized BLDC designs

KM 121 Motor Perf Curves

KM 121 Motor Perf Data

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Motor Constants

Torque constant (Kt): ~26.9 oz-in/A (≈ 0.19 Nm/A)
Back-EMF constant (Ke): ~20.4 V (line-to-line peak) per kRPM
Line-to-line resistance: ~0.05 Ω (excluding leads)
Line-to-line inductance: ~0.15 mH

Mechanical (Motor Core Only)

Construction: Frameless stator and rotor assembly
Stator outside diameter: ~121 mm
Air gap diameter: ~68.6 mm
Rotor poles: 8
Electromagnetic motor weight: ~3.0 kg

Not included:

Shaft
Bearings
Housing
Encoder or Hall sensors
Motor controller

Mechanical drawings exist for reference and integration, but this listing includes only the motor core .

Typical Applications

Custom electric bikes or scooters
Small electric motorcycles
Robotics and autonomous vehicles (AGVs)
Electric karts or light EV conversions
R&D, prototyping, and educational projects

Condition & Quantity

Condition: New-in-box (never used)
Manufacture date: Early 2000s (2001–2003)
Quantity available: ~800 units
Bulk purchases welcome; pricing negotiable for volume orders.

Brand	Kollmorgen
Unit Type	Unit
Unit Quantity	384

New Brushless DC Motor (Frameless) – 36–48V – High-Torque EV / Robotics Use

Specifications