Bōsōzoku

Bōsōzoku (暴走族^?, literally "running-out-of-control (as of a vehicle) tribe") is a Japanese youth subculture associated with customized motorcycles.

The word bōsōzoku is also applied to motorcycle subculture with an interest in motorcycle customizing, often illegal, and making noise by removing the mufflers on their vehicles so that more noise is produced. These bōsōzoku groups sometimes ride without motorcycle helmets (which in Japan is illegal), also engage in dangerous or reckless driving, such as weaving in traffic, and running red lights. Another activity is speeding in city streets, not usually for street racing but more for thrills. With many bikes involved, the leading one is driven by the leader, who is responsible for the event and is not allowed to be overtaken. Japanese police call them Maru-Sō (police code マル走 or 丸走) and occasionally dispatch police vehicles to trail the groups of bikes for the reason of preventing possible incidents, which may include: riding very slowly through suburbs at speeds of 5–10 mph, creating a loud disturbance while waving imperial Japanese flags, and starting fights that may include weapons (such as wooden swords, metal pipes, baseball bats and Molotov cocktails). These bōsōzoku gangs are generally composed of people under the legal adult age, which in Japan is 20 years old.

They were first seen in the 1950s as the Japanese automobile industry expanded rapidly. The precursors to the bōsōzoku were known as kaminari zoku (雷族^?, "Thunder Tribe"), urban motorcyclists more akin to the British rockers. Many, if not most, bōsōzoku members came from a lower socioeconomic class and may have used the motorcycle gang activities as a way to express disaffection and dissatisfaction with Japanese mainstream society.

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