Traffic Characteristics of Motorcycles on Tangent Sections of Expressways

In early 2005, the Taiwan government announced a 6-month pilot project permitting motorcycles with engine capacity over 250 cc to go on Expressways 68 and 72. Because of the long-term ban on motorcycles traveling on the expressways, motorists have limited experience in sharing the roads with motorcyclists. Therefore, it is essential to investigate traffic characteristics of motorcycles on expressways from a safety viewpoint. Traffic characteristics of motorcycles on the tangent sections of expressways were investigated during the trial period. The survey showed that motorcycles traveled faster than did other types of vehicles. The mean speed of motorcycles reached 86 km/h, 8 km/h faster than other vehicles. The 85th percentile speed was 108 km/h, 18 km/h higher than the posted speed. Motorcyclists kept shorter following distances than did other drivers, and other types of vehicles tailgated motorcycles as well. Most motorcyclists rode in the center-to-right of the inside lane and the center-to-left of the outside lanes. This study found a few cases in which motorcyclists shared the same lane, sometimes side by side with other vehicles, on the road. Although no motorcycle crash was reported during the trial period, episodes of speeding, tailgating, and lane sharing caused significant safety concerns for riders and drivers on the expressways. It was recommended that the government strictly enforce the laws against speeding, tailgating, improper overtaking, and driving in the same lane. In addition, it is essential to educate expressway users about sharing roads safely.