Vehicle Segment:
The Yamaha MX100 was a popular entry-level to mid-range motocross bike in the early 1980s, known for its performance and agility.
Key Competitors:
Competed with similar displacement models from Honda (e.g., CR125R), Suzuki (e.g., RM125), and Kawasaki (e.g., KX125) during its production run.
Manual Value Proposition:
Provides exact manufacturer part numbers and detailed visual aids, indispensable for accurate part sourcing and successful DIY repairs or restoration projects.
Diagram Utility:
Exploded diagrams are critical for understanding the order and orientation of assembly for complex components like the engine and transmission.
Covered Components:
Engine, Transmission, Chassis, Suspension, Brakes, Electrical System, Fuel System, Exhaust System, Bodywork, Controls
Estimated Page Count:
Highly comprehensive, likely exceeding 150 pages based on typical Yamaha parts catalogs of this era.
Type:
Parts Manual / Parts Catalog / Parts List
Engine Assembly:
Complete breakdown of the engine, including cylinder, piston, crankshaft, connecting rod, carburetor, ignition system, and cooling components.
Transmission And Drivetrain:
Details on gearbox components, clutch assembly, shift mechanism, and final drive sprocket/chain.
Chassis And Frame:
Exploded views of the main frame, subframe, swingarm, and related mounting hardware.
Suspension System:
Front forks (including internal components like springs and dampers) and rear shock absorber/linkage system components.
Braking System:
Front and rear brake assemblies, including levers, cables, calipers, master cylinders, brake shoes/pads, and drums/rotors.
Fuel And Intake System:
Carburetor components, fuel tank, petcock, fuel lines, and air filter assembly.
Exhaust System:
Exhaust pipe, muffler, and mounting hardware details.
Electrical System:
Ignition system components (CDI, spark plug, coil), lighting (if applicable), wiring harness, and switches.
Controls And Ergonomics:
Handlebars, levers, throttle assembly, footpegs, and shifter components.
Wheels And Tires:
Spokes, rims, hubs, bearings, and tire specifications.
Assembly Guidance:
Detailed exploded diagrams serve as a visual guide for correct part placement and assembly order.
Disassembly Guidance:
Essential for understanding how to take apart components for inspection, cleaning, or replacement.
Part Identification:
Crucial for ordering the correct replacement parts by providing manufacturer part numbers.
Visual Inspection:
Enlarged views aid in identifying worn or damaged components during a visual inspection.
Depth:
Component-level detail for every part, enabling identification of specific fasteners, seals, and internal mechanisms.
Part Number Accuracy:
Provides definitive manufacturer part numbers, eliminating guesswork and ensuring the correct replacement parts are ordered.
Compatibility:
PDF format is universally compatible with PC and MAC, and all versions of Windows.
Searchability:
PDF format allows for text searching (if OCR'd), making it efficient to locate specific part numbers or descriptions.
Printability:
Designed for high-quality printing, allowing users to print specific pages as needed.
Delivery Method:
Instant Download (Digital)
Digital Format Features:
Searchable text (likely OCR'd for ease of navigation), zoomable diagrams for clarity.
Engine Type:
Two-stroke, single-cylinder
Displacement:
Approximately 97cc (exact figures may vary slightly by specific year sub-model, but this is the defining characteristic of the '100' designation)
Bore X Stroke:
Typical for this era might be around 50mm x 49.6mm (specifics confirmed by manual).
Horsepower:
Estimated 14-16 HP (typical for a 100cc motocross bike of this period).
Torque:
Torque figures are generally not highlighted in parts manuals, but would be commensurate with its horsepower output.
Carburetor Model:
Likely a Mikuni VM series carburetor (e.g., VM24SC or similar), with specific jetting details found in a service manual, but parts are listed here.
Fuel Type:
Pre-mix gasoline (typically 40:1 or 50:1 ratio of gasoline to two-stroke oil).
Ignition Type:
CDI (Capacitor Discharge Ignition)
Spark Plug Replacement:
Typically every 20-30 hours of riding or as needed based on performance. Specific part numbers for spark plugs are found in the catalog.
Air Filter Cleaning:
Frequent cleaning (every few rides) recommended for optimal engine performance and longevity. Parts catalog will list the air filter element and related hardware.
Chain And Sprocket Maintenance:
Regular lubrication and tension adjustment are critical. Replacement parts (chains, sprockets) are listed.
Transmission Oil:
Yamalube (or equivalent SAE 80W transmission oil), capacity approximately 0.8 liters. Specific oil grade confirmed in service manual, but parts for the drain plug and oil seal are listed.
Fork Oil:
Yamaha specific fork oil or equivalent SAE 10W fork oil is typical. Capacity per fork leg approximately 150cc. Parts for fork seals and dust boots are crucial.
Coolant:
This is an air-cooled engine, so no coolant is required.
Typical Wear Items:
Piston rings, clutch plates, wheel bearings, swingarm bushings, and carburetor jets are common wear items needing replacement over time.
Carburetor Troubleshooting:
Carburetors can be prone to clogging from fuel varnish or debris, requiring cleaning and re-jetting. The parts manual provides all internal carburetor components.
Suspension Rebuild:
Fork seals are prone to leaks, and rear shock absorbers can lose damping over time. The manual lists all necessary seals and internal fork components.
Yamaha Motorcycles:
Yamaha has a long and successful history in motocross, starting with their early DT and YZ models, building a reputation for performance and durability.
Mx Series:
The MX series was Yamaha's line of motocross bikes preceding the more modern YZ designations, with the MX100 filling the 100cc class niche.
Manufacturing Location:
Likely manufactured in Japan by Yamaha Motor Company.
