Masaharu Okazaki - OS Giken Japan

OS Giken Japan - a brief history of excellence

In the vibrant era of the 1960s, a visionary named Masaharu Okazaki embarked on a pioneering quest. His dream was to craft Japanese race engines that could rival the triumphant European masterpieces of that era, engines that were synonymous with championship victories. With no arsenal but a fervent passion for motorsports and a remarkable aptitude for learning, he delved into the intricate world of mechanics within the confines of his garage. He meticulously dissected components, unravelled their secrets, and conceived enhancements to elevate their performance.

Masaharu Okazaki, a self-taught maestro in the realm of mechanics, initially immersed himself in the world of motorcycles before venturing into the expansive universe of four-wheeled marvels. His journey led to the inception of OS Giken in the early 1970s, a company built on the pillars of strength, durability, and the relentless pursuit of high performance. These founding principles continue to guide the development of OS Giken parts, positioning the company as a beacon of quality, performance, and durability in the automotive world.

From the modest beginnings of Mr. Okazaki, experimenting and innovating with motorcycle parts, OS Giken has traversed a journey of evolution and growth. It has sculpted its legacy as a premier manufacturer of racing drivetrain components, earning accolades and reverence from the global automotive community. Established officially in 1973, the heart of OS Giken, its headquarters and manufacturing hub, pulsates in Okayama, Japan.

The tale of OS Giken Japan is one of ambition and pioneering strides, sparked by a dream to engineer a race engine symbolising peak performance and unwavering reliability, called the TC-24 engine. The company, fuelled by this aspiration, embarked on a transformative journey, revealing the intricate subtleties and vulnerabilities within the driveline, the lifeline transferring power from the TC-24 engine to the wheels. The early stages of rigorous testing brought to light the limitations in the clutch, especially its torque capacity. This insight was a catalyst, steering the development of a robust clutch, envisioned to complement their groundbreaking race engine perfectly. The quest for perfection extended to refining the transmission, leading to a holistic enhancement of every element of the driveline. OS Giken developed special gears as the OE gearboxes were not strong enough to handle the power generated by the TC-24 engine.

This exploration enriched OS Giken with invaluable insights and experience, laying the foundation for the creation of products that would raise the benchmarks of automotive performance and reliability. During this transformative period, the escalating popularity of drag racing in Japan saw a surge in demand for high-performance clutches. It was a time when the exhilarating world of drag racing was captivating Japan, creating a burgeoning demand for uprated clutches capable of transferring the immense power of racing machines. OS Giken, with its innovative and performance-oriented clutches, emerged as the harbinger of power transfer in this thrilling era, earning a distinguished reputation as a premier “clutch shop”.

OS Giken Super Lock LSD

As the automotive terrain evolved and diversified, OS Giken, with its adaptive spirit and innovative DNA, recognized the need to craft differentials to meet the eclectic demands of the racing world. This realisation birthed innovations like the “Street Master” clutch and the OS Giken Super Lock LSD, each a masterpiece in automotive design and performance.

The “Street Master” clutch, renowned for its innovative design and optimised metal clutch disc, mitigates engagement issues and enhances durability, handling up to 700BHP. The OS Giken Super Lock LSD, with its superior design, guarantees unparalleled performance and reliability, it is simply another masterpiece, showcasing the company’s engineering prowess and commitment to superior design. It features larger and more numerous friction plates, a total of 24, setting it apart from its counterparts and ensuring reliability.

OS Giken’s commitment to innovation and craftsmanship is vividly illustrated in the development of the OS 88 sequential transmission and within the intricate workings of their advanced manufacturing facility. This is where meticulous precision and craftsmanship coalesce to forge automotive components, each echoing engineering excellence and detailed precision. The OS 88 sequential transmission is a marvel, a tangible representation of OS Giken’s dedication to pioneering products. Every facet of the OS 88, from its superior steel alloy construction to its distinctive tooth pitch, mirrors the company’s commitment to quality and superior performance. Later OS Giken also developed OS-FR5 (5 speed) and OS-FR7 (7 speed) sequential gearboxes for more general use and fitment.

OS Giken OS 88 sequential transmission
The manufacturing facility in Okayama, Japan is a hub of innovation where advanced technology and expert craftsmanship intertwine to create products that stand out for their quality and innovative design. It’s in this space that components like the OS Giken Super Lock LSD and the revolutionary “Street Master” clutch are meticulously crafted. This facility is more than a production unit; it’s a sanctuary every product is a manifestation of engineering brilliance and detailed craftsmanship. It’s here that innovative techniques, such as the use of rotating devices called indexes are employed to manufacture parts while they rotate, showcasing the innovative spirit of OS Giken. OS Giken has also revived in their facility the TC-24 engine using current technology. 


OS Giken manufacturing facility in Okayama, Japan

New products are currently in development at OS Giken Japan, like the new LSD called Dual Core LSD which is a hybrid LSD of mechanical and helical LSD. For those who seek something stronger than R4C clutch, OS Giken Japan will be adding R4E to their line-up soon, available for limited models. The  TC-16 (4 cylinder engine) is also being revived. 
OS Giken’s journey is not just a chronicle of technical advancements but a symphony of engineering brilliance and relentless pursuit of innovation and perfection. As the automotive landscape continues to evolve and transform, OS Giken embraces the challenges and opportunities that arise, constantly seeking avenues for enhancement and innovation. The company stands as a symbol of what can be achieved when passion meets innovation, continuing to inspire and lead the way in the world of automotive engineering.

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