John Lloyd, PhD, CPE, ACTAR

The number one cause of motorcycle crashes involving other vehicles is a left-turning driver across the rider’s path. In every case, the intruding motorist explains that they “did not see the approaching motorcycle”. The motorcycle was not conspicuous.

Expectancy

How can a motorist fail to see something as large as a modern motorcycle? The answer – expectancy. According to the National Highway Transportation Safety Authority (NHTSA), motorcycles account for only 0.6% of total vehicle miles traveled in the United States. Thus, motorists have more than a 99% expectancy that the next vehicle they see will NOT be a motorcycle. Through experiential learning drivers have learned to look for other automobiles, not motorcycles.

It is not that a motorist does not see the motorcycle. However, it does not meet their expectation and therefore they may fail to identify the approaching motorcycle. 

What can motorcyclists do to reduce their risk of collision when a driver causes a path obstruction at an intersection? According to human factors research, roadway users respond to hazards based on available information. They fail to respond when the available information is insufficient. Based on my experience as a motorcycle rider and human factor expert, conspicuity is key to increasing the information available to motorists. As motorcyclists we need to take responsibility to make our presence known to other roadway users. 

Many opportunities to improve conspicuity are available, which generally fall into two categories – audible and visual. Many riders are familiar with the concept “Loud pipes save lives”, as often declared on stickers affixed to their helmets. However, since noise intensity decreases as a function of the distance-squared, loud pipes are only effective in close proximity. Moreover, the greater volume is actually behind the motorcycle, not in front.

Human Factors research teaches that to improve driver detection and therefore avoidance of motorcycles on the road, we can enhance our visual conspicuity by following a few simple guidelines. These are captured by the acronym CAPLETS, which includes Contrast, Anticipation, Pattern, Lighting, Eccentricity, Time of Exposure, and Size.

Conspicuous Contrast

Contrast addresses the ability of a motorcycle and rider to stand out from their environment. For example, a black motorcycle on an asphalt surface is more difficult to distinguish than a yellow or red bike, especially under nighttime conditions. The same is true for the rider. Dark clothing makes it more difficult for a motorcyclist to be detected on the roadway. Brighter colors, especially high-vis yellow or orange, are more likely to create a greater contrast and therefore be more recognizable. 

Anticipation Conspicuity

Anticipation refers to the expectation of a given event. When motorcyclists ride together in a group, motorists are more likely to expect and therefore look for additional motorcycles. For this reason, a group riding together is often safer than a solo motorcyclist traveling alone.

Conspicuous Patterns

Patterns aid recognition by relying on one’s past experiences. Obviously, most motorists are familiar with the shape or pattern of a motorcycle and can easily distinguish one during daytime conditions. However, at night the pattern exhibited by a single headlight, may not aid a driver in identifying an approaching motorcycle. Motorcycles equipped with additional lighting that outlines its shape are more likely to be recognized on the roadway and hence less likely that their path will be intruded by a motorist.

Conspicuous Lighting

The purpose of Lighting is somewhat self-explanatory. More lighting means more information for other roadway users. Lighting is beneficial not just at night, but also during the day. The photograph, below, of one of my motorcycles illustrates how effective additional lighting is in providing information necessary to motorists to recognize my presence on a motorcycle. Headlight modulators can also increase conspicuity by switching between low and high beam automatically at a rate of approximately 4 times per second. The modulators are equipped with a light sensor, which turns off this feature at night. I have personally installed headlight modulators on several of my bikes and can attest as to their effectiveness.

Eccentricity

Eccentricity relates to the viewing angle. When a motorcycle is approaching an intersection, the viewing angle of the rider to an automobile on the right, waiting to make a left turn across the roadway is close to zero. Whereas, for the driver at the road junction, their viewing angle, unless properly turning their head to look for oncoming vehicles, is close to 90 degrees. There is not much that a rider can do to improve the motorists viewing angle. However, I have found that, when approaching an intersection at which a driver is waiting to make a turn across my path, by moving my motorcycle side to side within my lane helps to catch their attention. 

Time of Exposure

Time of Exposure. It is critically important at intersections to ensure that no visual obstructions exist between the rider and motorist that could limit time available to detect your presence. If fixed obstructions, such as trees or signage, are present I will position my motorcycle in a manner that provides a clear line of sight. Whereas, if a vehicle in front of or to the right of my motorcycle may pose a potential visual obstruction at an approaching intersection, I will move forward, or drop back, allowing a clear 3-second window between myself and other vehicles, thereby affording a waiting motorist every opportunity to detect and identify me on the road. Speed can also negatively affect time of exposure. At greater speeds other drivers have less available time to detect a motorcyclists presence. For this reason, I advise that it is best to travel at or within 5 mph of the posted speed limit. 

Conspicuous Size

Size matters, when it comes to conspicuity. Remember that motorists are looking for other automobiles. Larger motorcycles tend to be identified more quickly than smaller bikes, or bicycles. An opportunity may exist to make your motorcycle appear larger than reality through the use of additional lighting, such as led lights mounted on left and right side mirrors, and/or by the front wheel axle. 

Please call Dr. Lloyd at 813-624-8986 or email DrJohnLloyd@Tampabay.RR.com to discuss how he can be of help to you with your case.