Cycling comfort on different road surfaces

The increased awareness for the environment and steadily higher costs for gasoline makes bicycles more and more attractive for short-distance traffic. Due to this the infrastructure of cycling pathways gets more important not only for safety reasons but also for the aspect of cycling (dis)comfort. Comfortable cycling requires smooth rolling at lowest possible energy input. To better understand this relationship, the objective of the study was to determine rolling resistance and the resulting accelerations due to external agitations for different surfaces. Rolling resistance was quantified using a one degree of freedom pendulum (transversal rotation). By setting it at an initial angular displacement the measured decay of oscillations is a direct measure for the rolling resistance. To investigate the vibrations, an accelerometer was applied under the seat of a racing bicycle. The cyclist had to roll over a distance of 15 m at 3 different velocities with no pedaling. Four different surfaces were investigated. An effective value factor was defined for an overall description of the observed data. The covered distance of the pendulum is directly related to the rolling resistance and varied from 22,1 m on concrete slabs to 10,2 m on cobblestones. Asphalt and self-binding gravel rank in between. This ranking however changes when analyzing the vibrations. Lowest effective value factors were measured on asphalt (0, 05) whereas concrete slabs (0, 17), self-binding gravel (0, 21) and cobblestones (0, 57) are far behind. Comfort decreases with higher velocities. The results of this study allow suggestions about the best surface for cycling pathways thus making the systematic design of comfortable bicycle lanes easier. Designing bike lanes for comfort is an important issue to persuade more people to use the bike, especially the elderly population.