For anyone who has spent hours on a highway, they know that a loud helmet is more than just an annoyance—it's a safety issue. Wind noise causes fatigue and can damage a rider's hearing over time. At SPIRIT, a significant part of our R&D is dedicated to the quest for a quieter, more aerodynamically stable motorcycle helmet. While we don't own a full-scale wind tunnel, we leverage advanced computational fluid dynamics (CFD) software, the same kind used in aerospace, to simulate how air flows over the helmet at high speeds. This allows us to identify and eliminate sources of turbulence that cause noise. We refine the shape of the shell, the design of the visor seal, and the placement of ventilation ports to create the smoothest possible airflow. We design neck rolls and chin curtains that seal the bottom of the helmet to prevent turbulent air from rushing in from below. This obsession with aerodynamics results in a motorcycle helmet that is not only quieter but also more stable, reducing the neck fatigue that plagues so many riders.