YZ125 YZ250 1988-1993 WR250Z 1991-1993 Clymer Yamaha Motorcycle Repair Manual

Description

This Clymer Yamaha YZ125-250 1988-1993 WR250Z 1991-1993 Repair Manual provides detailed service information, step-by-step repair instruction and maintenance specifications for 1988-1993 Yamaha YZ125, 1988-1993 Yamaha YZ250, 1989-1990 Yamaha YZ250WR, and 1991-1993 Yamaha WR250Z motorcycles.

1988 1989 1990 1991 1992 1993

Includes everything you need to know to perform tune-up and routine maintenance on your Yamaha motocross and woods bike engine, clutch and transmission, fuel and exhaust, ignition system, steering and suspension, wheels, brakes and tires, electrical system, frame and body. Features complete wiring diagrams and 488 illustrated pages.

Table of Contents

QUICK REFERENCE DATA

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

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

THREE, LUBRICATION, MAINTENANCE AND TUNE-UP
Pre-ride checklist, Maintenance schedule, Tires and wheels, Lubricants, Cleaning solvent, Engine lubrication, Periodic lubrication, Periodic maintenance, Engine tune-up, Storage

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

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

SIX, CLUTCH, KICKSTARTER AND EXTERNAL SHIFT MECHANISM
Right-hand crankcase cover, Clutch cover (1989-on YZ125, 1990-on YZ250, 1990 YZ250WR and 1991-on WR250Z), Clutch release mechanism (1989-on YZ125), Clutch release arm (1988 YZ125, YZ250, YZ250WR and WR250Z), Exhaust governor assembly, Clutch, Clutch service (1988 YZ125), Clutch service (1989-on YZ125, YZ250, YZ250WR and WR250Z), Clutch inspection (all models), Primary drive pinion gear, Clutch cable, Kickstarter and idler gear, External shift mechanism

SEVEN, TRANSMISSION AND INTERNAL SHIFT MECHANISM
Transmission operation, Transmission troubleshooting, Transmission, Transmission overhaul (YZ125), Transmission overhaul (YZ250, YZ250WR and WR250Z), Transmission inspection, Internal shift mechanism

EIGHT, FUEL AND EXHAUST SYSTEMS
Air filter, Carburetor operation, Carburetor service (1988 YZ125), Carburetor service (1988 YZ250 and 1992-on WR250Z), Carburetor service (1989-on YZ125, 1989-on YZ250, 1989-1990 YZ250WR and 1991 WR250Z), Carburetor cleaning and inspection (all models), Carburetor float height adjustment, Carburetor rejetting, Fuel tank, Fuel shutoff valve, Exhaust system, Exhaust system repair

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

TEN, LIQUID COOLING SYSTEM
Safety precautions, Cooling system inspection, Radiator, Water pump, Hoses

ELEVEN, FRONT SUSPENSION AND STEERING
Front wheel, Front hub, Rim and spoke service, Tire changing, Tire repairs, Handlebar, Steering head, Front fork, Fork service (1988), Fork service (1989-on)

TWELVE, REAR SUSPENSION
Rear wheel, Rear hub, Driven sprocket, Drive chain, Tire changing and tire repairs, Shock absorber (1988), Shock absorber (1989-on), Rear swing arm and linkage (all 1988 and 1989 YZ250 and YZ250WR), Rear swing arm and linkage (1989-on YZ125, 1990-on YZ250, 1990 YZ250WR and 1991-on WR250Z), Swing arm side clearance, Bearing replacement, Sub-frame and back stay

THIRTEEN, BRAKES
Disc brake, Front brake pad replacement, Front caliper (1988), Front caliper (1989-on), Front master cylinder, Rear brake pad replacement, Rear brake caliper, Rear master cylinder, Brake hose replacement, Brake disc, Brake bleeding

INDEX

WIRING DIAGRAMS