In Japan, there is little discussion about traffic signal control for bicycle traffic. Bicycle traffic running through roadway obeys traffic signal for automobiles. However, since clearance interval of traffic signal for automobiles is decided based on automobile’s speed, it is inadequate for bicycle traffic and then there is some possibility of leaving bicycle traffic at signalized intersections when traffic lights change. In this study, observation survey was conducted at some signalized intersections and the collected data were used to analyze problems of bicycle’s clearance. As a result, there were some factors, for example, traffic signal control and geometric structure of signalized intersection, of leaving bicycle traffic in signalized intersections. Analysis also found that clearance interval for bicycle traffic that is calculated by using the speed of bicycles was larger than that of traffic signal for automobiles. From the results of observation survey, this paper mentioned knowledge for making a guideline of traffic signal control considering bicycles.
