How CIRRUS Works

Our simple 3-step process to real-world aero testing


Set Up

CIRRUS requires a bicycle with a power meter. The system then adds on three extra sensors Alto-Stratus (for wind speed, direction and altitude), FORMA (for body position), and our wheel speed sensor.



The cyclist rides along a course with less than 1% gradient, for approx 600m to 1000m. Ideally, the course needs to be relatively straight and free from too many bumps or obstructions - cycle paths and local roads are usually suitable.



As they ride, data collected from the sensors is stored on a data logger, and then uploaded to the cloud system. Precise aerodynamic drag measurements from the sensor combination can then be instantly viewed on the portal.

What's Included

• Alto-Stratus Wind Sensor

• FORMA Body Position Sensor

• TEMPO Speed Sensor

• Data Logger

• Access to Ride Portal

Results & Analysis

The Rider Portal

• Performs all calibrations and calculations required for precise aerodynamic drag measurement seamlessly and automatically so that users can focus on improving performance

• Delivers precise and simple data in a clear layout - no need for technical knowledge

• Allows comparison of data between multiple rides

• View if implemented changes are improving or degrading performance quickly

Wind Sensor


Our patented four port sensor design measures wind speed with 0.2% accuracy, wind direction with 0.1 degree precision, altitude, and air density. Accurate aerodynamic drag measurement can be taken in almost any wind conditions that are safe to cycle in. In addition, the pressure sensors in the probe are designed to eliminate any water ingress.

Road gradient is measured through matching multiple barometric measurements with GPS locations, providing a precise elevation profile along the course. Undulations and mild gradients are measured and accounted for, allowing for a greater availability of test locations.

Body Position Sensor


About 75% of a cyclists drag comes from the rider’s body position. The FORMA body position sensor consists of three infrared lasers which measure a cyclist’s head and chest position on the bicycle, ensuring that any movement that takes place while the rider is testing can be accounted for. Real-time visual feedback from the sensor is fed back via the Streamlines app, which runs on most Garmin bike computers.

Speed Sensor


Our proprietary wheel speed sensor measures time to the microsecond level. This greater precision is instrumental to the CIRRUS system drag measurement overall accuracy. The TEMPO is also at least ten times greater than other existing speed sensor market options.

Why Choose CIRRUS

Essentially, the CIRRUS system has optimised the entire aerodynamic testing process, from start to finish, so that riders, coaches, fitters and manufacturers can perform multiple end-to-end tests in as little as two hours, even in windy conditions.

The portal interface allows the user to see simple and clear data that highlights performance improvements (or degradations) without needing any understanding of the calculations and automatic calibrations happening behind the scenes.

Request Commercial Information

If you are interested in the CIRRUS system and would like to learn about our B2B lease deal, please fill the form bellow and we will get in touch with you. Alternatively you can email us at