The KTM 400 LC4 and 660 LC4 models from 1998 represent a significant offering in the dual-sport and adventure motorcycle segment. These Austrian-engineered machines are characterized by their powerful, liquid-cooled, single-cylinder LC4 engines, known for robust torque delivery and off-road capability. The LC4 platform, a long-standing cornerstone of KTM's lineup, was recognized for its durable construction and performance-oriented design, appealing to riders who demanded versatility and reliability in varied terrain. Key features include strong single-cylinder power, capable suspension systems, and a rugged chassis built for demanding use.

This comprehensive workshop repair service manual provides in-depth coverage for all models and repairs, from basic maintenance to complete overhauls. It details procedures for engine systems, including overhaul, lubrication, cooling, fuel, and ignition; drivetrain systems, covering clutch and gearbox; and chassis systems, encompassing suspension, steering, brakes, wheels, and the electrical system. The manual includes scheduled maintenance, repair procedures, diagnostic guides, detailed torque specifications, wiring diagrams, and information on special tools, making it an essential resource for owners and technicians to maintain, troubleshoot, and repair their KTM LC4 motorcycles.