Just a reminder: 99% of bicycle fatalities involve a collision with a motor vehicle — and bike helmets do not protect against that type of impact. If you don’t want to take my word for it, then here is Eric Richer, Giro’s Brand Development Manager, explaining it:
“There are many misconceptions about helmets, unfortunately,” says Giro’s Richter. “We do not design helmets specifically to reduce chances or severity of injury when impacts involve a car. As mentioned earlier, the number of variables is too great to calculate – the speed of the car, the mass, the angle of impact, the rider, the surface, the speed of the rider, did the driver or rider swerve a little or hit the brakes before impact. All of these variables and more are unique in every instance, and there is no way to accurately predict what is going to happen or the forces involved.
“What we do is work to make riders more visible, create helmets that provide relevant coverage so that riders wear them whenever they ride, and advocate for better infrastructure to help reduce the chances that you’d encounter an impact with a car.”