Why Do Motorcycles Have Their Drive Chains on the Left Side?

Why do motorcycles typically have their drive chains on the left side? If you walk into my shed and count the motorcycles, you'll notice that out of the five, only one has its drive chain on the left. This suggests that the choice of drive side is often made arbitrarily, based on factors deemed more important by the designers and engineers than the mere presence of a drive chain on one side.

The Logic Behind Left-Handed Drive Chains

My guess is that the drive chain placement on the left can be attributed to a combination of design and historical factors. First, consider the dominant handedness of the majority of the population. Most people are right-handed, which means that the majority of individuals prefer using their right side—whether it's their right hand, leg, or even the right side of their brain (since the left hemisphere is typically responsible for motor control on the right side of the body, and vice versa).

Historical Context: Right-Handed Dominance and Kick Starts

Back in the days when motorcycles were much different from what we know today, there was no self-start functionality. Instead, motorcycles were started by hand cranking or kick-starting. The reason for placing the kickrod on the right side is quite intuitive. People generally prefer to use their right leg for tasks that require leg strength and coordination, such as kicking. It would have been difficult for designers to place both the kickrod and the drive chain on the same side. Therefore, they opted to design the machine in a way that prioritized the right leg for starting operations, and consequently, the drive chain was placed on the left.

Standardization and Convenience

This design choice became a standard, and over time, it was adopted as a convention in motorcycle design. The placement of the drive chain on the left side was not just a matter of convenience but also a result of ergonomic and practical considerations. For mechanics, manufacturers, and riders alike, it made sense to place the drive chain on the side that was already being used more for starting the motorcycle. This further solidified the standardization of the left-handed drive chain as a widely accepted and adopted practice in the motorcycle industry.

The Evolution of Motorcycle Design

The left-handed drive chain is just one aspect of the evolution of motorcycle design. Over time, as technology advanced and motorcycle design became more sophisticated, engineers and designers continued to refine and improve various aspects of the motorcycle, including the drive chain placement. However, the fundamental choice of the left side for the drive chain has remained a standard due to its inherent practicality and the long-standing tradition in the industry.

Visualizing the Consequence

For someone like me, who has the misfortune of having only one motorcycle with a left-side drive chain in a shed full of motorbikes, it’s a stark reminder of how these seemingly minor design choices can become ingrained in the industry. The drive chain’s placement on the left side is not just a quirky detail but a result of historical and practical considerations that continue to influence motorcycle design today.

Conclusion

While the majority of motorcycles feature their drive chains on the left side, this choice is more than just an arbitrary design decision. It is a reflection of historical practices, ergonomic considerations, and the convenience for riders and mechanics. Understanding these factors provides insight into the intricate process of motorcycle design and the methods by which practical and efficient solutions are implemented.

So, if you ever wonder why motorcycles have their drive chains on the left, remember that it’s not just a fluke but a well-thought-out design choice that has stood the test of time.

Question and Answer

Q: Why is the drive chain on the left side of motorbikes?

A: The drive chain is placed on the left side of motorbikes due to historical and practical reasons. Initially, kick-starts required the use of the right leg for power, making it convenient to place the drive chain on the left side. This became a standard in motorcycle design and continues to be used today for ergonomic reasons and convenience during maintenance and operation.