Starting Problems; Engine; Fuel System; Electrical Systems - Yamaha YZF-R1 1998 Service Manual

EB900000
NOTE:
The following guide for troubleshooting does not cover all the possible causes of trouble. It
should be helpful, however, as a guide to basic troubleshooting. Refer to the relative proce-
dure in this manual for checks, adjustments, and replacement of parts.

STARTING PROBLEMS

ENGINE

Cylinders and cylinder head(-s)
• Loose spark plug
• Loose cylinder head
• Damaged cylinder head gasket
• Worn or damaged cylinder
• Incorrect valve clearance
• Incorrectly sealed valve
• Incorrect valve-to-valve-seat contact
• Incorrect valve timing
• Faulty valve spring
• Seized valve
Pistons and piston rings
• Incorrectly installed piston ring
• Damaged, worn or fatigued piston ring
• Seized piston ring
• Seized or damaged piston
Air filter
• Incorrectly installed air filter
• Clogged air filter element
Crankcase and crankshaft
• Incorrectly assembled crankcase
• Seized crankshaft

ELECTRICAL SYSTEMS

Battery
• Faulty battery
• Discharged battery
Fuses
• Blown, damaged or incorrect fuse
• Incorrectly installed fuse
Spark plugs
• Incorrect spark plug gap
• Incorrect spark plug heat range
• Fouled spark plug
• Worn or damaged electrode
• Worn or damaged insulator
• Faulty spark plug cap
Ignition coils
• Damaged ignition coil
• Broken or shorted primary or second-
ary coils
• Faulty spark plug lead
STARTING PROBLEMS
TROUBLESHOOTING

FUEL SYSTEM

Fuel tank
Fuel pump
Fuel cock
Carburetors
Ignition system
Switches and wiring
Starting system
9 - 1
• Empty fuel tank
• Clogged fuel filter
• Clogged fuel tank breather hose
• Clogged rollover valve (California only)
• Clogged rollover-valve-to-fuel-tank
hose (California only)
• Deteriorated or contaminated fuel
• Faulty fuel pump
• Faulty fuel pump relay
• Clogged or damaged fuel hose
• Deteriorated or contaminated fuel
• Clogged pilot jet
• Clogged pilot air passage
• Sucked-in air
• Damaged float
• Worn needle valve
• Incorrectly installed needle valve seat
• Incorrect fuel level
• Incorrectly installed pilot jet
• Clogged starter jet
• Faulty starter plunger
• Incorrectly adjusted starter cable
• Faulty ignitor unit
• Faulty pickup coil
• Faulty main switch
• Faulty engine stop switch
• Broken or shorted wiring
• Faulty neutral switch
• Faulty start switch
• Faulty sidestand switch
• Faulty clutch switch
• Incorrectly grounded circuit
• Loose connections
• Faulty starter motor
• Faulty starter relay
• Faulty starting circuit cutoff relay
• Faulty starter clutch
TRBL
SHTG