YAM YZ125-250; WR250Z 88-93

MODELS COVERED:

YZ125 (1988-1993)
YZ250 (1988-1993)
YZ250WR (1989-1990)
WR250Z (1991-1993)

This Yamaha motorcycle manual is 488 pages.

QUICK REFERENCE DATA

CHAPTER ONE / GENERAL INFORMATION
Manual organization / Notes, cautions and warnings / Safety first / Service hints / Washing the bike / Torque specifications / Fasteners / Lubricants / RTV gasket sealant / Threadlock / Parts replacement / Optional parts / Basic hand tools / Precision measuring tools / Special tools / Fabricating tools / Mechanic's tips / Ball bearing replacement / Oil seals / Safety / Specifications

CHAPTER TWO / TROUBLESHOOTING
Operating requirements/ Troubleshooting instruments / Starting the engine / Starting difficulties / Engine starting troubles / Engine performance / Engine / Engine noises / Two-stroke pressure testing / Fuel system / Ignition system / Clutch / Transmission / Drive train noise / Front suspension and steering / Rear suspension / Frame noise / Brakes / Specifications

CHAPTER THREE / LUBRICATION, MAINTENANCE AND TUNE-UP
Pre-ride checklist / Maintenance schedule / Tires and wheels / Lubricants / Cleaning solvent / Engine lubrication / Periodic lubrication / Transmission oil level check and change / Front fork oil change and oil level adjustment / Drive chain lubrication / Swing arm bearing assembly lubrication / Relay arm and connecting rod lubrication / Kickstarter spline lubrication / Front fork dust and oil seal cleaning and lubrication (1989-on) / Periodic maintenance / Drive chain cleaning and adjustment / Clutch adjustment / Throttle cable adjustment / Air filter service / Fuel valve cleaning / Sprocket bolt tightness / Coolant change / Engine tune-up / Cylinder head nuts torque / Spark plug / Ignition timing (CDI) / Carburetor idle speed adjustment / Idle speed and mixture adjustment / Carbon removal / Storage / Specifications

CHAPTER FOUR / ENGINE TOP END
Engine principles / Engine lubrication / Cleanliness / Servicing engine in frame / Cylinder head / Cylinder and power valve / Piston, wrist pin and piston rings / Reed valve assembly / Engine break-in / Specifications

CHAPTER FIVE / ENGINE LOWER END
Servicing engine in frame / Engine / Engine sprocket / Countershaft oil seal replacement / Crankcase and crankshaft / Specifications

CHAPTER SIX / CLUTCH / KICKSTARTER AND EXTERNAL SHIFT MECHANISM
Right-hand crankcase cover / Clutch cover / Clutch release mechanism / Clutch release arm / Exhaust governor assembly / Clutch / Clutch service / Clutch inspection / Primary drive pinion gear / Clutch cable / Kickstarter and idler gear / External shift mechanism / Specifications

CHAPTER SEVEN / TRANSMISSION AND INTERNAL SHIFT MECHANISM
Transmission operation / Transmission troubleshooting / Transmission / Transmission overhaul / Transmission inspection / Internal shift mechanism / Specifications

CHAPTER EIGHT / FUEL AND EXHAUST SYSTEMS
Air filter / Carburetor operation / Carburetor service / Carburetor cleaning and inspection / Carburetor float height adjustment / Carburetor rejetting / Fuel tank / Fuel shutoff valve / Exhaust system / Exhaust system repair / Specifications

CHAPTER NINE / IGNITION SYSTEM
Component testing / Capacitor discharge ignition / Flywheel rotor / CDI unit / Ignition coil / Spark plug / Engine stop switch / Wiring diagrams / Specifications

CHAPTER TEN / LIQUID COOLING SYSTEM
Safety precautions / Cooling system inspection / Radiator / Water pump / Hoses / Specifications

CHAPTER ELEVEN / FRONT SUSPENSION AND STEERING
Front wheel / Front hub / Rim and spoke service / Tire changing / Tire repairs / Handlebar / Steering head / Front fork / Specifications

CHAPTER TWELVE / REAR SUSPENSION
Rear wheel / Rear hub / Driven sprocket / Drive chain / Tire changing and tire repairs / Shock absorber / Rear swing arm and linkage / Swing arm side clearance / Bearing / Sub-frame and back stay / Specifications

CHAPTER THIRTEEN / BRAKES
Disc brake / Front brake pad / Front caliper / Front master cylinder / Rear brake pad / Rear brake caliper / Rear master cylinder / Brake hose / Brake disc / Brake bleeding / Specifications

INDEX

WIRING DIAGRAMS