The Invisible Danger: Why Motorcycles and Cyclists Are Harder to Spot at Junctions and How We Can Improve Safety

Published by Chris Kriel on



The Invisible Danger: Understanding Why Motorcycles and Cyclists are Harder to Spot at Junctions

When approaching a junction, drivers often find it easier to see cars and trucks than motorcycles or cyclists. This discrepancy poses a significant safety risk and is underpinned by several statistical and perceptual factors. By understanding these factors, we can improve road safety for all users.

Size and Conspicuity

One of the primary reasons motorcycles and bicycles are harder to spot is their smaller size compared to cars and trucks. This reduced visibility, or conspicuity, means they are less likely to be noticed by drivers, especially in complex traffic environments or at intersections. Research has shown that drivers are less likely to fixate on motorcycles than on cars or trucks when scanning intersections, a factor that significantly contributes to accidents.

Speed Misjudgment

Another critical factor is speed misjudgment. Drivers often underestimate the speed of smaller vehicles. Studies indicate that smaller objects, like motorcycles and bicycles, are perceived to be moving slower than they actually are. This misperception can lead drivers to believe they have more time to cross a junction than they actually do.

Visual Scanning Patterns

Human visual scanning patterns also play a role. Drivers tend to scan the road for larger, more familiar objects like cars and trucks. This habitual pattern of visual attention can result in the failure to notice smaller vehicles such as motorcycles or bicycles. Research using eye-tracking technology supports this, showing that drivers are less likely to fixate on motorcycles than on cars or trucks.

Daytime Conspicuity

Daytime conspicuity, or the ability to be seen during the day, is another issue. Motorcycles and bicycles can blend into the background, especially during bright sunlight. The lack of large, reflective surfaces and the smaller frontal area of motorcycles and bicycles can make them harder to detect. This blending effect reduces the likelihood of these smaller vehicles being noticed by other road users.

Motion Camouflage

Motorcycles and bicycles are more susceptible to a phenomenon known as motion camouflage, where they appear to remain stationary against a background despite moving. This can occur due to their smaller size and the linear path they often take, making it difficult for drivers to detect their approach. The concept of motion camouflage is supported by research in visual perception, where the brain processes smaller, linearly moving objects differently from larger ones.

A-pillar Obstruction

The design of vehicles can also obscure motorcycles and bicycles from a driver's view. The A-pillars (the pillars on either side of the windshield) can hide motorcycles and bicycles at certain angles, particularly at junctions. This is less of an issue for larger vehicles like cars and trucks, which are more likely to be seen even if partially obscured.

Horizontal vs. Vertical Expansion

An interesting perceptual difference involves the way vehicles expand in a driver's visual field. Cars and trucks primarily expand horizontally as they approach, a strong and easily perceived cue indicating they are getting closer. In contrast, motorcycles and bicycles, being taller and narrower, may seem to expand more vertically. This vertical expansion can be less intuitively processed by drivers, disrupting their ability to accurately judge the speed and distance of these smaller vehicles.

Practical Implications and Recommendations

Understanding these factors highlights the need for improved safety measures for motorcycles and cyclists at junctions. Several strategies can help mitigate these risks:

  • Enhanced Visibility: Motorcyclists and cyclists should use bright, reflective clothing and add auxiliary lights to increase their visibility.
  • Driver Awareness Training: Increasing awareness among drivers about the presence and risks associated with motorcycles and bicycles through training programs.
  • Infrastructure Improvements: Design improvements at intersections, such as better lighting and clear sightlines, can enhance the visibility of all road users.

By addressing these perceptual and statistical factors, we can make our roads safer for everyone. Increased awareness, better training, and thoughtful infrastructure design are key steps towards reducing accidents involving motorcycles and cyclists at junctions.


1. Speed Misjudgment: Horswill, M. S., & Helman, S. (2003). "A Behavioral Comparison between Motorcyclists and a Matched Group of Non-Motorcycling Car Drivers: Factors Influencing Accident Risk." Accident Analysis & Prevention.
2. Visual Scanning Patterns: Crundall, D., & Underwood, G. (1998). "The Role of Experience in Hazard Detection and Perception." Accident Analysis & Prevention.
3. Visual Scanning Patterns: Hole, G. J., Tyrrell, L., & Langham, M. (1996). "Some Factors Affecting Motorcyclists' Conspicuity." Ergonomics.
4. Daytime Conspicuity: Olson, P. L., & Farber, E. (1979). "Forensic Aspects of Driver Perception and Response." Lawyers & Judges Publishing Company.
5. Motion Camouflage: Ross, H. E., & Lishman, J. R. (1972). "Visual Perception of Motion during Briefly Delayed Vibration." Nature.
6. A-pillar Obstruction: Langham, M. P., & Moberly, N. J. (2003). "The effect of vehicle roof pillar size on motorcyclist conspicuity." Accident Analysis & Prevention.
7. Horizontal vs. Vertical Expansion: Cutting, J. E., & Vishton, P. M. (1995). "Perceiving layout and knowing distances: The integration, relative potency, and contextual use of different information about depth." In W. Epstein & S. Rogers (Eds.), Handbook of Perception and Cognition: Perception of Space and Motion.