This manual covers the 250/350 Series motorcycles, specifically the 353 and 354 model codes, produced primarily from the mid-1950s through the 1960s. , a historically significant Czechoslovakian brand, is renowned for its robust, accessible, and versatile motorcycle designs. The 250/350 Series models represent core offerings from the post-WWII era, known for their reliability and enduring appeal to enthusiasts. These air-cooled, two-stroke twin-cylinder machines, available in displacements of approximately 248 cc and 343 cc, feature a 4-speed constant mesh gearbox and a wet multi-plate clutch. Their engineering quality and straightforward design have made them popular among owners, hobbyists, and independent repair shops seeking to maintain these classic vehicles. This Factory Service & Repair Workshop Manual provides comprehensive guidance for the maintenance and repair of your 250/350 Series motorcycle. It covers a wide array of systems, including complete engine overhaul, transmission service, electrical system troubleshooting, fuel system maintenance, braking system adjustments, suspension and steering service, chassis lubrication, bodywork, and wheel/tire care. The manual includes detailed procedures for routine maintenance, troubleshooting guides, repair instructions, and overhaul procedures, all supported by hundreds of detailed photos and exploded diagrams. Its professional-standard content ensures that owners and technicians have the necessary information to perform all aspects of vehicle care, from basic adjustments to complete rebuilds, ensuring the longevity and optimal performance of these vintage machines.