1973-1981 Honda ATC 90 & 110 Three-Wheeler Shop Manual

Honda ATC 90 & 110: Technical Documentation

• Covers 1973–1981 Honda ATC 90 and ATC 110 three-wheelers, detailing engine, chassis, and electrical system service for the US90 and ATC90K variants
• Official Honda factory publication P/N 6291806, released in 1980
• Includes 116 pages of exploded-view diagrams, electrical schematics, and mechanical assembly illustrations
• Files stay accessible through your account for permanent reference after the initial download
• Indexed layout ensures quick navigation through engine, steering, transmission, and braking component sections
• This 1980 edition remains the primary reference source for the transition from the earlier US90 to the ATC90K3, specifically documenting modifications to the drive mechanism and steering assembly

Component and System Documentation

This Honda ATC 90 & 110 service manual provides structured technical data for the maintenance of air-cooled three-wheeler platforms. The document details disassembly and reassembly processes for the engine, drivetrain, front fork, and steering head components, including specific guidance on handling the clutch assembly and internal transmission gear sets.

Technical content includes comprehensive sections on the recoil starter, carburetion adjustments, and cylinder head servicing. Experts will find the manual presents clear exploded-view diagrams illustrating the sequence of snap rings, oil seals, and bearings required for engine housing and hub maintenance.

Specification and Reference Values

Specification highlights include factory-defined tolerance charts for piston rings, valve guides, and clutch plates, providing the standard values and serviceable limits necessary for evaluating component wear. Fluid capacities are documented at 1.0 liters for engine oil and 6.5 liters for fuel, with SAE 10W-40 specified for crankcase lubrication.

Torque values for major assemblies are clearly listed, such as cylinder head nuts at 14.5–18.1 lbs-ft (1.5–2.0 kg-m) and rear driven sprocket bolts at 29–34.7 lbs-ft (4–4.8 kg-m). Understanding what an OEM service publication covers assists in planning maintenance for these classic three-wheelers.

Note: This page is a contents overview for the manual. It does not provide repair or diagnostic instructions. This official 116-page Honda factory publication covers 1973–1981 Honda ATC 90 and ATC 110 three-wheelers, providing technicians with the necessary tolerances, assembly diagrams, and technical specifications for complete engine and chassis maintenance.