Abstract
While road traffic noise level is decreasing in Japan, the people living along trunk roads still have complaint against traffic noise. According to an official investigation, main target of the complaint is motorcycle. It is supposed that there are three reasons why motorcycle sound is annoying, which are increase in the number of motorcycles equipped with replacement muffler, increase in the number of imported motorcycles, and specialty of motorcycle sound quality. To solve this problem, administrative measures, technical measures and psychological measures are necessary. In the technical measures, improvement of noise measurement accuracy and evaluation of sound quality are important. On the other side, it is pointed out that electric vehicle is dangerous for pedestrians because of its quietness. It is difficult to improve vehicle sound quality and to solve electric vehicle issue by mechanical means only. Therefore electrical means will be necessary.
