Safety of motorised two wheelers in mixed traffic conditions: Literature review of risk factors

The ownership of motorised two wheelers (MTWs) has been on the rise across various countries across the globe. The growth has been especially higher in developing countries which have typical traffic characteristics and higher populations. This steady rise has resulted in increased accident and fatalities. This abrupt increase warranted attention from the researchers to carry out specific studies for MTWs, which have a very different behaviour as compared to cars in terms of physical and dynamic parameters. Moreover, the unique traffic patterns usually found in the developing countries pose an additional challenge to the researchers, since the conventional focus of transportation safety researchers was a homogeneous car-based traffic. Many such studies have been attempted, especially in the recent decades, which have considered various risk factors related to MTW safety. However, the studies have considered different sets of risk factors and have given surprising and even conflicting results. Therefore, a comprehensive review of the diverse studies needs to be carried out which incorporates all the risk factors considered in previous research. This study reviews such research papers which have analysed various risk factors related to safety of MTWs, especially in heterogeneous, non-lane based traffic. Specifically, this paper aims to incorporate results from those studies and highlight the conclusions from state of the art. The paper also discusses about the research gaps that are crucial for MTW safety in mixed traffic conditions. The review will be useful for researchers working in the field of MTW safety and for policy implementation and analysis.