Bosozoku literally translates to “violent running tribe,” it is a Japanese subculture that revolves around speed, thrills, and extreme customization of motorcycles or cars. This delinquent subculture originated in the 1950s when young kamikaze pilots came back from World War II. As the peak membership grew to around 42,000 in the 1970's and 1980's, the strict police crack downs in the 1990's and finally legislation in 2004 brought declining gang numbers. The Bosozoku style is currently seeing a resurgence as the more law abiding "Kyushakai" (Old Vehicle Clubs).

While redesigned, this bike is street legal and registered in Tucson, the factory bike chain and lock still intact, while rear turn signals are run through the frame, with a handmade dash, fairing and seat. The design, build and paint are by Cycle Skins Tucson. Upholstery is by Burley Biker's Custom Upholstery.

The 1983 Yamaha XJ750 Seca (often designated XJ750R) represents the height of early-1980s Japanese multi-cylinder engineering, combining high-tech innovation with sport-touring functionality. Named after California's famous Laguna Seca Raceway, this 748cc inline-four was designed to offer standard-class riders an intelligent, ultra-reliable machine capable of aggressive canyon carving or effortless long-distance cruising.

This specific model year represents the maturity of Yamaha's advanced XJ platform, featuring an unusually narrow engine profile and futuristic electronic amenities.

Historical Significance & Evolution

• YICS Engineering: The XJ750 featured Yamaha’s patented Yamaha Induction Control System (YICS). This cast intake tract sub-chamber optimized the fuel-air charge distribution inside the cylinders, drastically improving combustion efficiency and fuel economy.

• The "Ray Bradbury" Console: Far ahead of its time, the 1983 Seca featured a highly advanced onboard computerized monitoring system. A digital pre-ride checklist console actively checked critical biometrics, warning the rider of low engine oil, battery fluid, brake fluid, or burnt-out safety lights.

• Touring Adaptability: Facing fierce 750cc competition, Yamaha embraced the sport-touring market by offering the fully dressed XJ750RJ variant in 1983. This setup enclosed the raw Seca architecture inside a factory sports fairing with custom lowers, integrated saddlebags, and a matching trunk.

Production Run

1982–1985 (Replaced in 1984/1985 by the liquid-cooled five-valve XJ750F architecture)

Origin

Engineered and hand-assembled in Iwata, Japan

Market Packaging

Available as a bare, futuristic sport-standard or a factory-dressed "RJ" touring machine

Original MSRP

Approximately $4,099 USD for the premium, high-tech package

Technical Specifications

Engine & Powertrain

• Engine Type: 748cc air-cooled, four-stroke, transverse inline four-cylinder (DOHC, 2 valves per cylinder)

• Performance: 76 to 82 horsepower @ 9,000 RPM (depending on territory tuning and US vs. Euro restrictions)

• Bore & Stroke: 65.0 mm x 56.4 mm (9.2:1 compression ratio utilizing four Mikuni/Hitachi CV carburetors)

• Drivetrain: 5-speed manual transmission coupled to a low-maintenance, enclosed shaft final drive

Chassis & Performance

• Suspension: Steel double-cradle frame equipped with 36mm air-adjustable telescopic front forks (featuring integrated anti-dive valving) and dual rear shock absorbers

• Braking System: Dual hydraulic front discs (11.6-inch/298mm) and an internal expanding mechanical rear drum brake

• Curb Weight: 230 kg to 254 kg (507 lbs to 561 lbs) depending on naked vs. fully dressed touring gear

• Top Speed: 114 mph to 127 mph (183 to 204 km/h)