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General| Bore x Stroke | 54.0mm x 54.5mm |
|---|---|
| Ignition | CDI |
| Transmission | Constant-mesh 6-speed; multiplate wet clutch |
| Final Drive | Chain |
| Front Brake | Hydraulic disc, 270mm |
| Wheelbase | 58.3 in |
| Fuel Capacity | 2.1 gal |
| Tires (Front) | 80/100-21 |
| Length | 85.6 in |
| Width | 32.5 in |
| Engine Type | Liquid-cooled, 2-stroke, single-cylinder |
| Fuel Delivery | Keihin PWK38S carburetor |
| Front Suspension | KYB® spring-type fork with speed-sensitive damping; 11.8-in travel |
| Rear Suspension | KYB® single shock; 12.4-in travel |
| Rear Brake | Hydraulic disc, 245mm |
Overview of the Yamaha YZ series, its features, and the manual's purpose.
Highlights critical safety precautions for machine operation and maintenance.
States the machine is designed strictly for competition use on closed courses.
Lists essential special tools required for tune-up and assembly, with part numbers and usage.
Provides instructions for starting cold/warm engines and initial break-in procedures.
Detailed steps for the initial break-in period to ensure engine performance.
Lists key specifications for the machine, including dimensions, engine, and capacities.
Provides a schedule for regular inspection and lubrication based on usage intervals.
Details pilot screw adjustment and bleeding the hydraulic brake system.
Explains how to inspect brake pad thickness and replace front brake pads.
Explains how to inspect rear brake pad thickness and check brake fluid level.
Guides on inspecting the spark plug for condition and proper gap.
Explains how to check and adjust the engine's ignition timing.
Illustrates and lists parts for removing the cylinder head and cylinder.
Illustrates and lists parts for removing the piston and power valve components.
Illustrates and lists parts for removing the engine from the frame.
Guides on installing the engine back into the frame, including related components.
Illustrates and lists parts for removing the crankshaft.
Details installing the crankshaft, including using special tools and applying grease.
Illustrates and lists parts for removing the transmission components.
Provides instructions for installing the front and rear wheels, including bearings and brakes.
Details draining brake fluid and refilling the system.
Illustrates and lists parts for removing the front fork assembly.
Illustrates and lists parts for disassembling the front fork components.
Provides instructions for assembling the front fork components, including oil and settings.
Illustrates and lists parts for removing the steering assembly, including stem and bearings.
Illustrates and lists parts for removing the swingarm assembly.
Guides on installing the swingarm, including bushings, bearings, and collars.
Illustrates and lists parts for removing the rear shock absorber.
Guides on inspecting the damper rod, shock absorber, spring, and bearings.
Details installing the rear shock absorber assembly onto the frame.
Outlines inspection steps for diagnosing ignition system failures and spark plug issues.
Explains spark gap tests and checks for ignition coil resistance.
Explains the role of the carburetor and the importance of proper air-fuel mixture settings.
Provides a table correlating engine symptoms with carburetor adjustments.
Provides a chart for setting front fork characteristics based on symptoms.
Provides a chart for setting rear shock absorber characteristics based on symptoms.
