The Ninja 250R (model code EX250J) is an entry-level sportbike produced between 2008 and 2012, renowned for its aggressive styling, lightweight and nimble handling, and affordability. Designed to appeal to new riders and those seeking an accessible yet stylish motorcycle for commuting or recreational use, this model draws inspiration from larger Ninja series. Its engineering prioritizes a beginner-friendly riding experience, offering a manageable power output from its liquid-cooled, 249 cc parallel-twin engine, coupled with a responsive chassis that makes it easy to maneuver. The Ninja 250R has consistently been recognized as a strong contender in its segment, balancing performance, aesthetic appeal, and cost-effectiveness. This comprehensive workshop service repair manual provides detailed instructions for the complete service, repair, and maintenance of the Ninja 250R (EX250J) for the years 2008 through 2012. It covers all essential systems, including engine mechanicals, fuel injection, ignition, cooling, transmission, drivetrain, brakes, suspension, steering, and electrical systems, along with bodywork and frame. The manual includes step-by-step procedures for routine maintenance, engine overhauls, component replacements, and troubleshooting diagnostic guides, supported by high-resolution diagrams and exploded views. This resource is invaluable for owners, mechanics, and technicians aiming to maintain the optimal performance and longevity of their vehicle.