Our Secret Weapon in Development
CFD & Rapid Prototyping
Computational Fluid Dynamics (CFD) plays a fundamental role of our AVP; it operates within a closed development loop that integrates simulation, physical prototyping, and real-world validation.
In isolation, it allows us to analyse aerodynamic behaviour, long before a production rim exists, modeling airflow interaction across the entire wheel–tire system under a wide range of yaw angles & velocity. Using CFD, we can study how airflow attaches, separates, and re-energises around the rotating structure, informing decisions around rim depth, leading-edge geometry, sidewall curvature, and spoke integration.
However, CFD at Scribe is not a purely digital exercise.
We rapidly prototype new rim concepts using additive and short-run composite manufacturing, allowing us to mount tires and build complete test assemblies early in the process. These physical systems are then 3D scanned to capture the true mounted tire profile, casing deformation, and tire–rim interface geometry. This is critical because the aerodynamic behaviour of a wheel is heavily influenced by the tire shape under tension and inflation, not just the theoretical rim cross-section.
The scanned geometry is fed directly back into our CFD models, replacing theoretical shapes with accurate, real-world system models. From there, we can run higher-fidelity simulations that account for tire growth, tread transitions, and the complex interaction between rim, spoke structure, and rotating airflow. This iterative loop allows us to refine designs far beyond what static modeling would permit.
By continuously cycling between CFD simulation, rapid prototyping, tire fitment, scanning, and re-simulation, we’re able to evolve rim profiles with a system-level mindset, optimizing not just for peak drag numbers but for stability, yaw consistency, and performance across real riding conditions.
Wind-Tunnel Testing
Wind-tunnel testing remains one of the most valuable and reliable tools in high-performance wheel development, providing a controlled environment to isolate aerodynamic behaviour and measure performance with a high degree of repeatability. As a central element of our AVP (Augmented Validation Process), it runs alongside other validation systems while continuously producing performance data that feeds back into the development cycle.
Within the tunnel, we are able to evaluate complete wheel–tire systems across a range of yaw angles, air speeds, and configurations, allowing us to understand how airflow interacts with rotating structures in a controlled and measurable way. This includes analyzing drag behaviour, flow separation, and reattachment characteristics, as well as how rim depth, profile geometry, spoke architecture, and tire interface influence aerodynamic efficiency and stability. Because these variables can be isolated and repeated under identical conditions, the tunnel allows for meaningful comparison between iterations and against benchmark products.
Real-World Testing
Beyond controlled aerodynamic evaluation and benchmarking in the wind tunnel, we conduct on-road aerodynamic validation using AeroSensor systems to measure performance in real riding conditions.
Every new wheel platform undergoes extensive field testing to refine dynamic ride characteristics under real load. This includes in-house testing alongside structured validation with Scribe athletes, allowing us to assess performance across multiple variables such as compliance, vibration damping, structural stiffness, handling stability, and rolling efficiency.
The objective is not just to validate isolated aerodynamic performance but to ensure strong correlation between controlled test data and real-world riding outcomes where airflow is variable, surfaces are imperfect, and rider input forms part of the system.
This closed-loop process allows us to translate tunnel insights into tangible on-road performance.
