Cycling is my primary mode of transportation after air transit. Each time I get on a bike I have the choice of wearing a bike helmet, or not. I don’t wear a bike helmet each and every time I get on a bike. I wear a bike helmet selectively, just not on each and every ride. So when do I wear one and why?
Like many, riding a bike came to me early in life. I spent a good portion of my early teen years toodling around town with friends on my ten-speed. In those days wearing a bike helmet wasn’t something we thought about. It never happened. I didn’t own a helmet. My parents never thought about buying me one. But then this was also the era of riding in cars without a seat belt. Safety standards have changed. Also like many, riding disappeared from my life when I turned sixteen, got my driver’s license, and a car. Unlike many, I returned to cycling in a big way in my late forties.
Urban living has made cycling not only a realistic transportation choice, but often a more efficient and timely mode of transit. It was also a lifestyle choice for me brought on by a strong feeling that I needed more regular exercise. I hate running for exercise. I enjoy cycling in all of its forms. I have a collection of bikes.
My Specialized AWOL touring bike for serious rides
My Brompton folding bike for leisure and travel
My choice of ride depends on whether I am interested in exercise, running errands, or just trying to get somewhere.
I almost always wear a bike helmet when I’m out and about on my touring bike. I use this bike primarily for exercise and longer rides of more than five miles at a time. I average about 14-15mph during these rides. The high average speed and forward leaning riding position make wearing a helmet a safety necessity.
Conversely, I almost never wear a bike helmet when I’m using my Brompton folding bike. The riding position is much more upright and it is easy to step on and off quickly. It is great for short errands. I average about 9-10mph on this bike. Exercise is less the reason. The focus is just on getting there.
Speed is the major factor, in my opinion, in head injury or fatality risks associated with cycling. There are two perspectives on speed:
First, there is the risk of injury or fatality associated with the speed of cars in a collision. A car collision with a cyclist (or pedestrian) raises the risk of injury to the cyclist (or pedestrian) exponentially with the speed of the car. The speed of a cyclist (or pedestrian) is essentially irrelevant.
Second, there is the speed of the cyclist in non-car related crashes. There are no clear third-party statistics I could find on this. My personal experience suggests I am far less likely to incur a serious injury while traveling at 10mph than at 15 or 20mph. Reaction time is one factor here, but more importantly the type of bicycle and riding posture are important factors as well. When I am riding on my Brompton at a slower speed (8-10mph) and in an upright posture with a low crossbar the risk of injury is tremendously lower than if I am riding my touring bike at 15+mph in a hunched over posture (more aerodynamic) and with a high crossbar.
Articles on Cycling and Helmet Use
Bike Helmet Statistics from helmets.org
Pedestrian and Bicyclist Crash Statistics
Stamats Post Scripts 