Sustained 21 Nm direct-drive performance with a zero-cogging flat-wire motor and 21-bit magnetic encoder.
The MOZA R21 Ultra Direct Drive Wheel Base is designed for advanced PC sim racers who need strong, consistent force feedback across sprint and endurance sessions. Its next-generation flat-wire motor delivers 21 Nm of sustained torque rather than a short peak, while the 21-bit magnetic encoder resolves more than two million positions per revolution. A CNC-machined aluminium housing, intelligent cooling and multiple mounting orientations make the base suitable for rigid cockpits and professional-style installations.
Why choose this product?
- The zero-cogging flat-wire motor delivers sustained 21 Nm torque, preserving detail and resistance during long sessions without relying on a brief peak figure.
- A 21-bit magnetic encoder with 2,097,152 positions and 1000 Hz USB refresh rate captures fine steering input and rapid force-feedback changes.
Product details
Motor, force feedback and precision
The direct-drive motor is engineered to minimise cogging torque, creating smoother low-speed movement and more consistent force feedback through the steering range. MOZA's current force-feedback algorithm reproduces tyre load, road texture, kerb impacts and weight transfer, while the encoder provides the resolution required for small corrections. Supported iRacing setups can also use the published 360 Hz force-feedback mode.
Cooling, housing and safety
The base uses a CNC-machined aluminium-alloy housing with intelligent thermal monitoring and torque regulation. This management system is designed to maintain stable output during demanding use. Hands-off Protection can detect when the wheel is released and stabilise the steering response, while two RGB light strips can display configurable colours and telemetry effects.
Mounting, connections and software
Front, side and bottom mounting are supported, allowing the R21 Ultra to fit different cockpit plates and brackets. Rear ports are provided for power, PC, pedals, dashboard, shifter, handbrake and an optional emergency-stop switch. A compatible steering wheel is required; the MOZA KS Pro Steering Wheel is one verified current option. MOZA Pit House and the supported mobile app provide firmware, force-feedback, steering-angle and lighting configuration.
Compatibility
Platform: Windows PC.
Steering-wheel ecosystem: supports current compatible MOZA wheels through the MOZA quick-release system.
Requirements: a rigid mounting solution and compatible steering wheel are required. Pedals, steering wheel, cockpit bracket and emergency-stop switch are not included.
Specifications
Torque
21 Nm sustained
Motor
Zero-cogging flat-wire
Encoder
21-bit magnetic
Resolution
2,097,152 PPR
USB refresh rate
1000 Hz
Rated power
360 W
Input
110–220 V AC to 36 V DC
Dimensions
248.8 × 140 × 135 mm
Weight
9.0 kg
Mounting
Front, side and bottom
What's in the box?
- MOZA R21 Ultra Direct Drive Wheel Base × 1
- Power adapter × 1
- Power cord × 1
- Data cord × 1
- Bolt kit × 1
Frequently asked questions
Is the 21 Nm figure sustained or only a peak?
MOZA specifies 21 Nm as sustained torque, intended to remain available during extended and demanding sessions.
Does the wheel base include a steering wheel?
No. The R21 Ultra is supplied as a wheel base and requires a compatible steering wheel with the correct MOZA quick-release connection.
Which mounting methods are supported?
MOZA provides mounting provisions for front, side and bottom installation. The selected cockpit or bracket must be rated for high-torque direct drive.
What can be configured in MOZA Pit House?
Pit House supports firmware, force-feedback strength and filters, steering angle, hands-off protection, lighting and connected MOZA device settings.
Can pedals, a shifter and a handbrake connect to the base?
Yes. Dedicated rear ports are provided for compatible pedals, dashboard, shifter, handbrake and an optional emergency-stop switch.
Please note: we make every effort to display products as accurately as possible. Colours, materials and finishes may vary slightly in real life due to studio lighting, screen settings, ambient light and product characteristics.
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