Model Years Covered:
1974, 1975, 1976, 1977, 1978, 1979, 1980, 1981, 1982, 1983
Chassis Code General:
DT100 (specific codes may vary by year/market)
Segment:
Lightweight dual-sport motorcycle
Target Audience:
Off-road enthusiasts, commuters, general utility riders seeking an affordable and capable machine.
Key Competitors:
Honda CR125 Elsinore, Kawasaki KE100, Suzuki TS100, Hodaka Wombat.
Design Philosophy:
Yamaha's focus on reliability, simplicity, and accessible performance for trail riding and light off-road use.
Manual Value Proposition:
Empowers owners to perform maintenance and repairs themselves, saving money and extending the life of their vintage Yamaha.
Coverage Scope:
Comprehensive service, repair, maintenance, and troubleshooting for the Yamaha DT100 motorcycle range from 1974-1983.
Estimated Page Count:
Information not explicitly provided, but described as 'detailed' and 'highly detailed'.
Manual Type:
Service Repair Workshop Manual / Factory Manual / Repair Guide
Digital Format:
PDF (potentially zipped, requiring WinZip/WinRAR for extraction)
Engine:
Engine overhaul, assembly, disassembly, specifications, lubrication, cooling system (air-cooled), ignition system, carburetor adjustment.
Transmission:
Gearbox, clutch operation, assembly, disassembly, gear ratios, lubrication, maintenance.
Chassis And Frame:
Frame inspection, repair, suspension (front forks, rear shocks), steering system, wheel alignment, bearings.
Electrical System:
Lighting system, ignition system (CDI, points, etc.), battery maintenance, wiring diagrams, troubleshooting electrical faults, generator/alternator, starter (if applicable).
Fuel System:
Fuel tank, fuel lines, fuel petcock, carburetor service and tuning (e.g., Mikuni VM series), fuel filter.
Brakes:
Front and rear brake systems (drum or disc depending on year/variant), brake fluid, brake shoe/pad replacement, brake cable adjustment, hydraulic system maintenance (if applicable).
Lubrication:
Engine oil, gearbox oil, chain lubrication, chassis lubrication points, oil change intervals, oil specifications.
Bodywork And Trim:
Fenders, side covers, seat removal and maintenance, tank removal, handlebar components.
Locks And Security:
Ignition lock, steering lock maintenance.
Maintenance:
Scheduled maintenance, oil changes, filter replacements, chain adjustment, spark plug service, brake adjustments, tire pressure checks.
Troubleshooting:
Diagnostic procedures for common issues, problem-solving guides for starting problems, running issues, electrical faults, braking problems.
Repair And Rebuild:
Complete step-by-step instructions for engine rebuilds, transmission overhauls, suspension repairs, brake system servicing, electrical component replacement.
Restoration:
Detailed guidance for restoring components and the overall motorcycle.
Depth Of Information:
Highly detailed, suitable for professional technicians and DIY enthusiasts. Covers complete disassembly, repair, and reassembly of all major components.
Compatibility:
Windows (97, 2000, Me, XP, Vista, 7, 10), Linux, Mac
Extract Software:
WinZip or WinRAR recommended for zipped files
Printability:
Printable on any computer
Binding:
Digital Download (not a physical copy, no CD/DVD)
Paper Quality:
N/A (Digital)
Engine Type:
2-stroke, air-cooled, single cylinder
Displacement:
97 cc (for most models, slight variations may exist)
Bore X Stroke:
Approx. 52.0 mm x 45.0 mm (check specific year for exact figures)
Compression Ratio:
Typically around 6.5:1 to 7.0:1 (check specific year)
Induction:
Carburetor (e.g., Mikuni VM24SS or similar)
Horsepower:
Approximately 10-12 HP at ~6,000-7,000 RPM (varies by year and tuning)
Torque:
Approx. 9-10 Nm at ~5,000-6,000 RPM (varies by year)
Fuel Type:
Unleaded gasoline with 2-stroke oil premix (ratio typically 20:1 or 32:1, consult manual for exact specification)
Fuel Tank Capacity:
Approximately 6.0 - 8.0 liters (depending on year and specific model variant)
Overall Length:
Approx. 1970 mm (varies by year)
Overall Width:
Approx. 850 mm (varies by year)
Overall Height:
Approx. 1155 mm (varies by year)
Wheelbase:
Approx. 1305 mm (varies by year)
Dry Weight:
Approximately 90-100 kg (varies by year and equipment)
Wet Weight:
Approximately 95-105 kg (with fluids)
Oil Change Interval Engine:
Refer to manual: typically every 1,000 - 2,000 km or annually. Specific Yamaha recommendations should be followed.
Spark Plug Service Interval:
Refer to manual: typically every 2,000 - 4,000 km or annually.
Chain Lubrication Interval:
Every 500 km or after riding in wet conditions. Manual will specify type of lubricant.
Engine Oil Type:
2-stroke engine oil, specific API service classification and viscosity grade provided in manual (e.g., JASO FD or FC, SAE 10W-30 for transmission/clutch).
Transmission Oil Type:
Yamalube SAE 10W-30 API SE or higher is often recommended, or equivalent.
Brake Fluid Type:
DOT 3 or DOT 4 (if hydraulic disc brakes are equipped; consult manual).
Carburetor Gumming:
Common on older 2-strokes if fuel sits for extended periods. Requires cleaning and rebuilding.
Air Leaks Intake Manifold:
Can cause rough idle, poor performance. Requires inspection and replacement of seals.
Electrical Connection Corrosion:
Especially in humid or off-road environments. Requires cleaning and dielectric grease.
Suspension Seals Leaking:
Common with age and mileage. Requires fork seal replacement or rear shock rebuild/replacement.
