1984-1989 Honda ATC90/ATC110 Shop Manual
127 Pages • 12.45 MB • Instant, Printable PDF
Honda Models Covered & Key Technical Specifications
Models: Honda ATC90, Honda ATC110, US90
Sub-models / Variants: ATC90K2, ATC90K3
Model Years: 1973–1981, 1984–1989
Serial Numbers: ATC90E-1600001 and subsequent, ATC90-1600001 and subsequent
Technical Data:
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Engine displacement: 89 cc (5.48 cu in) or 89.5 cc
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Engine oil capacity: 1.0 US qt (0.91 L)
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Fuel tank capacity: 1.7 US gal (6.5 L)
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Compression ratio: 8.2:1
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Horsepower: 5.0–6.0 PS at 7,500 rpm
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Spark plug gap: 0.024–0.028 in (0.6–0.7 mm)
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Cylinder head bolt torque: 14.5–18.1 lbs-ft (1.5–2.0 kg-m)
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Rotor torque: 18.8–23.1 lbs-ft (2.6–3.2 kg-m)
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Wheel hub bolt torque: 14.5–17.4 lbs-ft (2–2.4 kg-m)
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Valve tappet clearance: 0.002 in (0.05 mm)
Honda Manual Features & Content Preview
When you have a classic three-wheeler on the lift, you need exact factory data, not guesswork. This 127-page Honda OEM shop manual breaks down the technical specifications, assembly schematics, and inspection values required to properly evaluate the 1973–1981 and 1984–1989 Honda ATC90, ATC110, and US90 models. Because working on vintage ATVs involves inherent physical risks, always verify safety tolerances and utilize appropriate shop equipment before beginning any major teardown.
Complete Component and System Specs
This publication goes far beyond basic lists. It provides the deep technical summaries necessary for core engine disassembly, final chassis alignment, and precise transmission adjustments.
- Comprehensive Model Coverage: Details the standard ATC90/ATC110 platforms alongside US90-based variants and the upgraded K-series builds.
- OEM Assembly Schematics: Features high-resolution exploded views and detailed wiring diagrams for accurate component tracing.
- Major Technical Revisions: Documents critical platform shifts, including the ATC90K3 chain guide, upgraded tensioner arms, and split-rim tubeless tire setups.
Critical Specification Highlights
To ensure accurate diagnostics, the manual includes comprehensive reference values for every major system. You will find exact tightening torque figures spanning from the cylinder head to the rotor assembly. The cylinder bore diameter standard is explicitly listed at 50.0–50.01 mm, complete with defined service limits for rebore procedures.
Electrical and valvetrain tolerances are equally detailed. The factory documentation specifies a valve clearance of 0.002 in (0.05 mm) for cold engine operation and notes a condenser capacity of 0.225–0.275 μF for ignition testing. Understanding exactly what an OEM service publication covers ensures you have the precise baseline values needed to get these machines back in the dirt reliably. Plus, because the file is an instant download, you can pull up these exact figures on your shop computer or tablet right now.
Customer Reviews
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