This is the fifth in a six part series on driving behaviors that are annoying or dangerous to bicyclists. Previously covered were "buzzing," the right hook, pulling out too close in front of the cyclist, and making a left hand turn too close in front of the cyclist. The next behavior is following too close behind a cyclist.
Unlike a car, a bicycle does not have brake lights. A cyclist slows by using his hands to squeeze the brakes. No lights come on indicating that a cyclist is braking. Accordingly, a driver that is following too closely behind will not automatically know a cyclist is slowing because no brake lights will come on indicating as much.
Oftentimes, this behavior is manifested when a cyclist is travelling downhill at a high rate of speed, often 30 or 40 miles per hour or more. Some vehicles for whatever reason, instead of leaving a 2 second gap (the distance the vehicle would travel in 2 seconds, i.e., at 40 mph, this would be 120 feet or about 6 car lengths) often will crowd the cyclist leaving only a car length or less. Because of perception/reaction time, which at a minimum most human factor specialists say is at least 1.5 seconds, there is no way that a driver could avoid hitting a cyclist if the cyclist unexpectedly went down at 40 mph with the driver less than a car length behind. Indeed, at that speed and distance, if the cyclist merely slowed the driver would have a very good chance of rear-ending the cyclist.
It’s hard to know why some motorists feel it is necessary to be so close to the cyclist. Maybe the motorist wants to be ready to pass the cyclist, maybe the motorist wants to intimidate the cyclist, and maybe the motorist simply is unaware of how dangerous it is to travel so closely behind the cyclist. Any way you cut it though, this is an annoying and dangerous driving behavior.
Obviously, as a cyclist, you need to make every effort to let the motorist know your intention, by signaling your turns and indicating that you are slowing (usually by placing your left hand behind you with an open palm). Hopefully, the driver will know what you mean. Be careful not to make abrupt movements and although it’s probably a last resort, if you really think you are going to be run down, it’s probably not a bad idea to exit the road as soon as you safely can do so.