Star Pro side view
Lars Boom winning that rainy stage at the Tour De France...big moment for me also.
Star Pro in the Arizona wind tunnel.
Riders could shut off all vents with the button at the rear of the helmet. This improved aerodynamics at the cost of ventilation.
Star Pro vent sliders, shown in white plastic, are actuated with the button at the top rear of the helmet.
Vent shut off sliders use variable means to actuate the closure panels in different directions to the direction of button movement. What is seen in this picture is hidden between the upper and lower bodies of the helmet.
We went to meet the athletes from the Belkin team when they were on the Tour of California. We were able to garner a lot of information from speaking to them.
gLike
Bell Star Pro Aerodynamic Helmet

Star Pro Helmet is an aerodynamic driven model.
Industrial Designer: Daniel Cram
Dan's ID mark can be seen in the shape, slider textures, and a general cosmetic control of everything visible to the user.

On the mechanical design side: Slider (vent shut off) system, bifurcated body construction, Float fit system, removable shield with on helmet storage, internal channeling and tooling cad release, manufacturing process, testing analysis and execution.

We met the Belkin team during the Tour of California to show them proto-types and discuss the direction the helmet was taking. Most of the athletes favored safety over aggressive styling or helmet thickness. It was said by one member of the Belkin team that anyone who had had a bad crash leans towards safety.

Gregg Jacobsen
Sr. Mechanical Design Engineer Santa Cruz, CA