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Itís a dirty little secret: motorcycle helmets can sometimes do more harm than good.
Optimized for high velocity impacts, when faced with low speed crashes their stiff energy absorbing EPS lining doesnít deform and can transfer too much energy to the wearerís skull.
Itís a compromise that saves lives, but leads to many minor concussions that could add up to major health problems down the road, especially among off-road riders who take a lot of low speed spills.
But now a small California startup company thinks it has the solution.
6D Helmets has developed a brain bucket that incorporates what it calls an Omni-Directional Suspension (ODS) system between the outer shell and EPS core.
Twenty-seven hourglass-shaped dampers, each comprised of two circular cups on either side of a rubber core, are positioned around the helmet and designed to provide a cushioning barrier against low speed impacts.
According to 6D, during a 4.5 mph impact the head of someone wearing one of its helmets experiences just 48 g of acceleration compared to 78 g for an average DOT or Snell-approved helmet. The threshold for a concussion in an adult male is around 60 g. At 9 mph, the point where conventional helmets typically start dissipating energy efficiently, the difference is still 97 g vs. 127 g.
Company founder Bob Weber, a lifelong racer and motorcycle industry professional, says the ability of the ODS dampers to move in three dimensions (giving them six degrees of freedom, hence the 6D name) also provides added protection during oblique impacts by reducing the angular acceleration energy that can lead to rotational brain injuries, something that current helmets are not required to address in certification tests.
Although slightly heavier than a conventional helmet, the extensive use of carbon fiber and Kevlar in the 6D design helps keep any weight penalty to a minimum. Weber plans to start selling off road versions of the helmets in February for about $750 a pop, so to speak.
As with all helmets, by law theyíre intended for single-impact use, even though their unique design could likely survive multiple low speed events.
A street legal version is also in the works, as is a bicycle helmet. Weber thinks the ODS technology is well suited to skate and snowboarding applications, and says thereís been interest in tapping it for military and football applications.
In the meantime, the 6D helmet will be on the track next year on the head of Honda AMA Supercross rider Eli Tomac. Of course, if heís as good as he probably thinks he is, 6D may never find out how well its invention actually works.