Bōsōzoku (暴走族, literally "running-out-of-control (as of a vehicle) tribe") is a Japanese youth subculture associated with customized motorcycles. The first appearance of these types of biker gangs was in the 1950s. Popularity climbed throughout the 1980s and 1990s, peaking at an estimated 42,510 members in 1982. Their numbers dropped dramatically in the 2000s with a reported number of under 7,297 members in 2012.
Bōsōzoku style traditionally involves boilersuits similar to those of manual laborers or leather military jackets with baggy pants, and tall boots. This uniform became known as the tokkō-fuku (特攻服, "special attack clothing") and is often adorned with kanji slogans. Typical accessories to this uniform are hachimaki, surgical masks, and patches displaying the Japanese Imperial Flag. Bōsōzoku members are known for taking a Japanese Road Bike and adding modifications such as over-sized fairings, lifted handle bars shifted inwards, large seat backs, extravagant paint jobs, and modified mufflers. Bōsōzoku styles take inspiration from American choppers and greasers.
Bōsōzoku first started as groups of returning World War II veterans. Many veterans were having a hard time readjusting to society after the panic of the war, and the most extreme turned to alternative methods to fuel their excitement. Many turned to custom car making and gang-like activities on city streets to gain an adrenaline fix. They gained many inspirations from American greaser culture and imported western films. This would explain the many similarities between old American biker culture and the bōsōzoku characteristics. Many younger individuals began to see this style of life as very appealing, especially marginalized individuals looking for change. Eventually, these youngsters took over the identity, becoming the foundation for the modern bōsōzoku. 
The 1970's were when the term of bōsōzoku first truly began to emerge. This was a period of time characterized by actual riots between police and many of these youth groups. The term, bōsōzoku, was not actually created by these biker groups, but was eventually widely adopted and used by these various groups. In the 1980s and 1990s, bōsōzoku would often embark on massed rides, in which up to 100 bikers would cruise together slowly en masse down an expressway or major highway. The motorcyclists would run toll booths without stopping and would ignore police attempts to detain them. New Year's Eve was a popular occasion for the massed rides. The bikers would sometimes smash the cars and threaten or beat up any motorists or bystanders who got in the way or expressed disapproval of the bikers' behavior. Participation in the gangs peaked at 42,510 members in 1982. This made bōsōzoku the prevailing form of youth delinquency within Japan.
Numbers slowly began to decline following the 1980's peak. It is reported that, by the 1990's there were around 28,000 bōsōzoku sprinkled throughout the country. In 2004, the Japanese government passed a revised road traffic law which gave the police more power to arrest bikers riding recklessly in groups. With increased arrests and prosecutions, bōsōzoku participation rapidly went into decline. As of 2010, police reported that the new trend among bōsōzoku was to ride together in much smaller groups and to ride scooters instead of heavily modified motorcycles. Aichi Prefecture was reported to have the highest number of riders, followed by Tokyo, Osaka, Ibaraki and Fukuoka. By 2015, there were only a reported 6,771 active bōsōzoku throughout Japan. In 2013, the National Police Agency re-classified bōsōzoku biker gangs as "pseudo-yakuza" organizations.
Bōsōzoku are usually between the ages of 16 and 20 years old. They are known for their style that heavily mimics greaser culture within the United States. This includes a pompadour style haircut, tokkō-fuku uniforms, which were often modified and embroidered jumpsuits, inspired by those worn by manual laborers during the WWII era, baggy pants and military boots.Tokkō-fuku were often embroidered with various slogans and large, intricate designs. They were seen as a status symbol to many, symbolizing both their pride in themselves and their strength. They were often worn open in the front, with bandage wrappings around their waist. They would also often by accompanied by rounded sunglasses and tasuki sashes. 
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 10-15 km/h, 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).
Bōsōzoku are known to modify their motorcycles in peculiar and showy ways, which are called Kaizōsha (改造車,"Modified Vehicles"). The general style of bōsōzoku bike modification appears to combine elements of an American chopper bike and a British café racer. Examples of modifications that are taken from these styles are raised handle bars like those on a chopper or over-sized fairings like those found on café racers (though bōsōzoku usually fit them much higher on the bike than their original position, and angled upwards at the front).
A typical customized bōsōzoku bike starts off by taking an average 250-400cc Japanese road bike, adding a shugo exhaust system (multiple tube header), squeezing the handlebars inwards (known as shibori), and adding a 3 or 4-trumpet horn- sanren or yonren, respectively. Loud paint schemes on the fenders or the gas tanks with motifs such as flames or kamikaze-style "rising sun" designs are also quite common. The bikes will often be adorned with stickers and/or flags depicting the gang's symbol or logo.
There are also marked regional differences in motorcycle modifications. For example, Ibaraki bōsōzoku are known to modify their motorcycles in an extensively colorful, flashy way. They will often have three or four oversized fairings in a tower-like way in and an abundance of lights.
In America it is common to hear Kaido Racers referred to as "Bosozoku", though this is not the case. They can often seem similar and can be seen on highways together in Japan, though they are two different things. More extreme "silhouette style" Kaido Racers often take inspiration from old race cars of the 80s. They add wide bodykits and huge wings, resembling the Group 5 "Special Production Cars" of the 1970s.
Ties to Organized Crime
In general, the Japanese government sees bōsōzoku as highly organized groups, affiliated under several national federations. They are known to be surprisingly well organized, despite generally only having a handful of members above the age of twenty. They also generally have clear cut rules, uniforms, symbols, and other marks of organization. Certain groups even have membership fees and set punishments. These groups, of course, also make up a large proportion of Japanese criminal activity, being involved in vandalism, road traffic violations, and other criminal activity.
Their lives of crime generally do not end after they turn twenty though. It is estimated that around 25% of bōsōzoku are above the age of twenty. Alongside that, they have been shown to have ties to various yakuza organizations. In fact, some numbers predict that as many as one-third of yakuza recruits come from one of a few bōsōzoku. However, as these groups become less common, their ties to the yakuza become less apparent, as they begin recruiting from other marginalized groups, such as the Japanese burakumin or Zainichi Koreans.
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- Osaki, Tomohiro (18 April 2013). "Documentary chronicles disappearing world of 'bosozoku'". The Japan Times.
- Callahan, Kat. "The Bosozoku Are Japan's Disappearing Rebels Without a Cause". Jalopnik.
- Callahan, Kat (October 4, 2014). "The Bosozoku Are Japan's Disappearing Rebels Without A Cause". Jalopnik.
- Osaki, Tomohiro (Dec 14, 2016). "Japan's 'bosozoku' bikers a vanishing rebel breed". The Japan Times.
- Kaplan, David E (2019). Yakuza : Japan's Criminal Underworld. University of California Press. pp. 124–126. ISBN 0520953819.
- Author, No (2010-07-17). "Aichi biker gangs up but downsized". The Japan Times. Retrieved 2020-11-14.
- "Tokyo cops accuse Chinese Dragon member in gashing of man with broken bottle". TokyoReporter. 2017-06-29. Retrieved 2020-11-14.
- John (2012-03-26). "The Rise and Fall of Bosozoku". Tofugu. Retrieved 2020-11-14.
- "Worn to be wild: Tokkōfuku combat uniforms". Deep reads from The Japan Times. Retrieved 2020-11-14.
- "'BOSOZOKU' AND YANKEE: ANOMY AND PARODY IN THE AFFLUENT SOCIETY - ProQuest". search.proquest.com. Retrieved 2020-11-14.
- Sato, Ikuya (1986). 'Bosozoki' and Yankee: Anomy and Parody in the Affluent Society (PhD). The University of Chicago. ProQuest 303443061.
- Writers, Yabai. "Bosozoku: The Craziest Autos in the World". YABAI.
- Carter Jung (2010-05-05). "Nissan Heritage Car Collection (Part 1 of 2)". Import Tuner Magazine. Archived from the original on 2012-03-04. Retrieved 2015-11-18.
- Fujisawa Toru. Shonan Junai Gumi (湘南純愛組！). Shonen Magazine Comics. ISBN 4-06-312257-3
- Greenfeld, Karl Taro. Speed Tribes: Days and Nights with Japan's Next Generation. New York: HarperCollins, 1994. ISBN 0-06-092665-1.
- Sato, Ikuya. Kamikaze Biker: Parody and Anomy in Affluent Japan. Chicago: University of Chicago Press, 1998. ISBN 0-226-73525-7.
- Sasaki, Hiroto, and Tokoro Jewzo. Bukkomi no Taku: Kaze Densetsu (特攻の拓). Shonen Magazine Comics. ISBN 4-06-312449-5.
- Yoshinaga, Masayuki. Bosozoku. London: Trolley Books, 2002. ISBN 0-9542648-3-5.
|Wikimedia Commons has media related to Bōsōzoku.|
- Metropolis magazine, Last of the Speed Tribes (general article about bōsōzoku culture and its decline)
- Vice, Life Inside Japan's Aging Biker Gangs (documentary about current and former bōsōzoku)
- Mookychick, Bosozoku japanese biker gangs and bosozoku style (key elements of bōsōzoku fashion)
- Bosozoku Style (blog showcasing bōsōzoku style cars)