David Zabriskie, Christian Vande Velde (Garmin-Transitions), Lance Armstrong (Team RadioShack) and a select few others have been spotted wearing new Giro time trial helmets – further developments of the experimental TT-284 lid we saw at last year's Tour.
As before, the new helmets sport a shortened tail that Garmin-Transitions directeur sportif Jonathan Vaughters says is more aerodynamic overall than the traditional long shape. He reckons you need to take into consideration that the rider's head doesn't stay glued in one position all the time.
The removable visor carries over as well, along with the lower rear cover that's been proven in the wind tunnel to be very effective. Neither helmet displays any external vents whatsoever – not even in the tail like before – which suggests to us that Giro have further progressed their internal channeling system.
The rear ends of the helmets differ between Zabriskie and Armstrong, with the former being distinctly more rounded and the latter sporting a far sharper tip. As it turns out, the one worn by the Garmin boys is a further evolution of the production model while Armstrong's was a fully custom helmet built especially – and only – for him called the 'LAX'.
Armstrong's LAX helmet better fills in the space normally left open at the base of his neck with off-the-shelf aero lids
In order to create the optimum helmet for Armstrong's physiology and unique, humpback riding position – and to get around the Texan's vigorous travel schedule – Giro's recently formed Advanced Concepts Group actually went so far as to take laser scans of his head and torso.
They then built a model that could be used for wind tunnel testing, and tested up to 100 prototypes in total. According to a press release, Giro have no plans to bring the helmet to production. However, certain design features will eventually find their way into future aero models.
Armstrong's helmet was finished off in a custom design to complement the custom construction and shape