OS Giken

From Mr. Okazaki's humble beginnings tinkering with motorcycle parts at home, OS Giken has evolved and grown over the years, building and cementing a reputation as one of the best racing drivetrain parts manufacturers in the world. Officially founded in 1973, the company headquarters and factory are located in Okayama, Japan. All OS Giken parts are 100% manufactured and assembled in Japan, under very strict quality-control guidelines.