Comparison of discomfort caused by speed humps on bicyclists and riders of motorized two-wheelers

Speed humps have been used extensively across the world as effective traffic calming measures. Speed humps are typically used in areas where interactions between motorized and non-motorized users are expected, such as residential areas, urban areas, near school zones, and shopping areas. In these areas, various other users including pedestrians and bicyclists would be present. However, the impacts of speed humps on the non-motorized users have not been explored well so far. In this study, an attempt is made in this direction, focusing on discomfort of bicyclists while passing over speed humps. An experiment is conducted using nine volunteers who were asked to ride instrumented bicycles and motorized two-wheelers over speed humps of varying geometry at different speeds and report the level of discomfort they felt in Borg CR 10 scale. The vibration values were also recorded. When the responses of riders were considered, it was observed that for the same speed, the bicyclists experienced higher discomfort than that by riders of motorized two-wheelers while passing over the humps. For the same geometry, the critical speeds after which the riders feel discomfort are much lower (about 4 km/h) for bicyclists than that of riders of a motorized two-wheeler.