Proposed standard method for motorcycle nomenclature system

There is a variety of definitions for the term `motorcycle' found in documents sources and past research. Manufacturers tend to categorize motorcycles according to engine displacement sizes, while researchers have the tendency to class them according to types, usage, mechanical function and the like. Aside from manufacturer's classification, most of these definitions and classifications of motorcycle are subjective. Due to the variations, research that directly relates to the motorcycle such as emission issues, impact of motorcycle design on ergonomics, and rider's protective gear against accidents is uncoordinated. Consequently, since the field of research is vast, consistency and reliability of data collected are questionable. This paper aims to fill this research gap by proposing a standardized method for easy and practical motorcycle nomenclature system, that is using a classification of motorcycles for ergonomics study that will aid future research on motorcycles.