2022 Kawasaki KLX140R Troubleshooting Guide Owner’s Manual

2022 Kawasaki KLX140R TROUBLESHOOTING GUIDE

TROUBLESHOOTING GUIDE

NOTE
This troubleshooting guide is not exhaustive and does not give every possible cause for each problem listed. It is meant simply as a quick guide to assist you in troubleshooting some of the more common difficulties.

Starting failure or difficulties

The starter motor does not rotate:

• Engine stop switch not position
• Starter lockout switch trouble
• Starter motor trouble
• Battery voltage low
• Starter relay not contacting or operating
• Starter button not contact
• Starter system wiring shorted or open
• Engine stop switch trouble
• Main fuse 10 A blown

The starter motor rotating but the engine does not turn over:

• Starter clutch trouble
• Starter idle gear trouble

The engine does not turn over:

• Valve seized
• Cylinder or piston seized
• Crankshaft seized
• Connecting rod small end seized
• Connecting rod big end seized
• Camshaft seized
• Transmission gear or bearing seized

Fuel does not flow:

• No fuel in the tank
• The fuel tap turned off
• Fuel tank cap air vent obstructed
• Fuel tap clogged
• Fuel line clogged
• Float valve clogged

Engine flooded:

• Fuel level too high
• Float valve is worn or stuck open
• Wrong starting technique

Spark missing or weak:

• The engine stop switch turned off
• Spark plug dirty, broken, or gap improperly adjusted
• Spark plug cap or high-tension wiring defective
• Spark plug cap not contacting properly
• Spark plug type incorrect
• Crankshaft sensor defective
• Igniter defective
• ignition coil defective
• Engine stop switch wiring defective
• Flywheel magneto damaged
• Wiring shorted or interrupted

Fuel/lair mixture incorrect:

• Idle adjusting screw improperly adjusted
• Pilot jet or air passage clogged
• Air cleaner element clogged, poorly sealed, or not installed

Compression low:

• Spark plug lose
• The cylinder head insufficiently tightened
• Cylinder or piston worn
• No valve clearance
• Crankshaft oil seal leak
• Valve spring broken or weak
• Valve not seating properly (valve bent, worn, or
• carbon accumulation on the seating surface)
• Piston ring worn, weak, broken, or sticking
• Piston ring side clearance excessive
• Cylinder head gasket damaged
• Cylinder head warped
• Cylinder gasket damaged

Poor low-speed performance

Spark weak:

• Spark plug dirty, broken, or gap improperly adjusted
• Spark plug cap or high-tension wiring defective
• Spark plug cap shorted or not contacting properly
• Spark plug type incorrect
• Igniter defective
• Ignition coil defective
• Crankshaft sensor defective
• Flywheel magneto defective
• The wiring connector is not in good contact

Fuel/air mixture incorrect:

• idle adjusting screw improperly adjusted
• Pilot jet, needle jet, or air passage clogged
• Air cleaner element clogged, poorly sealed, or not installed
• Choke valve closed
• Carburetor fuel level too high or too low
• Fuel tank cap air vent obstructed
• Carburetor holder lose
• Air cleaner duct lose
• Fuel tap clogged

Compression low:

• Spark plug lose
• The cylinder head was insufficiently tightened
• Cylinder or piston worn
• No valve clearance
• Valve spring broken or weak
• Valve not seating properly (valve bent, worn, or carbon accumulation on the seating surface)
• Piston ring worn, weak, broken, or sticking
• Piston ring side clearance excessive
• Cylinder head gasket damaged
• Cylinder head warped
• Cylinder gasket damaged
• Decompression trouble

Other:

• Igniter defective
• Brake dragging
• Clutch slipping
• Engine overheating
• Engine oil level too high
• Engine oil viscosity too high
• Ignition timing incorrect
• Drive chain trouble

Poor or no high-speed performance

Firing incorrect:

• Spark plug dirty, broken, or gap improperly adjusted
• Spark plug cap or high-tension wiring defective
• Spark plug cap shorted or not contacting properly
• Spark plug type incorrect
• Igniter defective
• ignition coil defective
• Crankshaft sensor defective
• Flywheel magneto defective
• The wiring connector is not in good contact

Fuel/air mixture incorrect:

• The main jet is clogged or the wrong size
• Jet needle or needle jet worn
• Jet needle clip in the wrong position
• Carburetor fuel level too high or too low
• Air cleaner element clogged, poorly sealed, or not installed
• Choke valve closed
• Fuel contaminated with water or foreign matter
• Fuel tank cap air vent obstructed
• Carburetor holder lose
• Air cleaner duct lose
• Fuel tap clogged
• Fuel line clogged
• Needle jet or air passage clogged

Compression low:

• Spark plug lose
• The cylinder head was insufficiently tightened
• Cylinder or piston worn
• No valve clearance
• Valve spring broken or weak
• Valve not seating properly (valve bent, worn, or
• carbon accumulation on the seating surface)
• Piston ring worn, weak, broken, or sticking
• Piston ring side clearance excessive
• Cylinder head gasket damaged
• Cylinder head warped
• Cylinder gasket damaged
• Decompression trouble

Improper acceleration:

• Choke valve closed
• Carburetor fuel level too high or too low
• The main jet clogged
• The throttle Main valve does not fully open
• Air cleaner element clogged
• Muffler clogged
• Fuel contaminated with water or foreign matter
• Brake dragging
• Clutch slipping
• Engine overheating
• Engine oil level too high
• Engine oil viscosity too high
• Crankshaft bearing is worn or damaged
• Ignition timing incorrect
• Crankshaft sensor defective

Knocking

• Carbon built up in combustion chamber
• Fuel quality poor or type incorrect
• Spark plug type incorrect
• Igniter defective

Engine overheating

Firing incorrect:

• Spark plug dirty, broken, or gap improperly adjusted
• Spark plug type incorrect
• Igniter defective

Fuel/air mixture incorrect:

• The main jet clogged or the wrong size
• Carburetor fuel level too low
• Carburetor holder lose
• Air cleaner element clogged, poorly sealed, or not installed
• The air cleaner duct is poorly sealed

Compression high:

• Carbon built up in combustion chamber

Engine overloaded:

• Brake dragging
• Clutch slipping
• Engine oil level too high
• Engine oil viscosity too high
• Drive chain trouble

Lubrication inadequate:

• Engine oil level too low
• Engine oil quality poor or type incorrect
• Clutch operation faulty-

Clutch slipping:

• No clutch lever play
• Clutch cable improperly adjusted
• Clutch cable defective
• Clutch plate worn or warped
• Clutch spring broken or weak
• Clutch release mechanism defective
• Clutch hub or housing unevenly worn

Clutch not disengaging properly:

• Clutch lever play excessively
• Clutch spring tension uneven
• Engine oil deteriorated
• Engine oil viscosity too high
• Engine oil level too high
• Clutch housing froze on drive shaft
• Clutch release mechanism defective
• Clutch hub nut loose
• Clutch plate warped or rough
• Clutch hub spline damaged

Gear shifting faulty

Transmission does not go into gear; shift pedal does not return:

• Clutch not disengaging
• Shift fork bent or seized
• Gear stuck on the shaft
• Shift mechanism arm spring broken
• Shift mechanism arm broken
• Shift return spring broken or weak
• Shift return spring pin lose
• Shift pawl broken
• Shift drum broken

Transmission jumps out of gear:

• Shirt Tork Worn
• Gear groove worn
• Gear dogs and/or dog grooves worn
• Shift drum groove worn
• Gear positioning lever spring broken or weak
• Shift fork pin worn
• Drive shart, output shart, and/or gear splines worn

Transmission skips gears:

• Gear positioning lever spring broken or weak
• Shift mechanism arm spring broken or weak

Engine noise abnormal

Knocking

• Carbon built up in combustion chamber
• Fuel quality poor or type incorrect
• Spark plug type incorrect
• Engine overheating
• igniter defective

Piston slap:

• Piston clearance excessive
• cylinder or piston worn
• Connecting rod bent
• Piston pin or piston pin holes worn

Valve noise:

Valve clearance incorrect
Valve spring broken or weak
Camshaft bearing or cam face worn

Other noise:

• Connecting rod small end clearance excessive
• Connecting rod big end clearance excessive
• Piston ring worn, broken, or stuck
• Piston seized or damaged
• Cylinder head gasket leaking
• Exhaust pipe leaking at the cylinder head
• Crankshaft runout excessive
• Engine mounts loose
• Crankshaft bearing worn
• Camshaft chain tensioner trouble
• Camshaft chain, sprocket, chain guide worn
• Flywheel magneto lose

Abnormal drive train noise

Clutch noise:

• Clutch housing/friction plate clearance excessive
• Clutch housing gear excessive
• Metal chip jammed in clutch housing gear teeth

Transmission noise:

• Crankcase bearing won or damaged
• Transmission gear is worn or chipped
• Metal chip jammed in gear teeth
• Engine oil level or viscosity too low

Drive chain noise:

• Drive chain slack improperly adjusted
• Drive chain worn
• Rear and/or engine sprocket(s) worn
• Drive chain inefficiently lubrified
• Rear wheel misaligned
• Frame noise abnormal

Front fork noise:

• Oil level or viscosity too low
• Spring broken or weak

Rear shock absorber noise:

• Shock absorber damaged

Disc brake noise:

• Pad installed incorrectly
• Pad surface glazed
• Brake disc warped
• Brake caliper defective
• Brake cylinder damaged

Other noise:

• Bracket, nut, bolt, etc. improperly mounted or tightened

Exhaust smoke

Excessively white:

• Piston oil ring worn
• Cylinder worn
• Valve oil seal damaged
• Valve guide worn
• Engine oil level too high

Black smoke:

• Air cleaner element clogged
• Main jet is too large or has fallen out
• Choke valve closed
• Carburetor fuel level too high

Brownish

• Main jet too small carburetor fuel level too low
• Air cleaner duct lose
• Air cleaner poorly sealed or missing

Poor handling and/or stability

Handlebar hard to turn:

• Cable, wiring incorrectly routed
• Steering stem nut too tight
• Screening stem Dearing damaged
• Steering stem bearing inadequately lubricated
• Steering stem bent
• Tire air pressure too low

Handlebar shakes or vibrates excessively:

• Tire worn
• Swingarm bushing damaged
• Rim warped or out of balance
• Front and/or rear axle runout excessive
• Wheel bearing worn
• Handlebar clamp lose
• Steering stem head nut lo0se

Handlebar pulls to one side:

• Frame bent
• Rear-wheel misaligned
• Warm bent or twisted
• Swingarm pivot shaft runout excessive
• Steering maladjusted
• Steering stem bent
• Front fork bent
• Right/left front fork oil level uneven

Shock absorption unsatisfactory (suspension too hard):

• Front fork oil excessive
• Front fork oil viscosity too high
• Front fork bent
• Tire air pressure too high

Shock absorption unsatisfactory (suspension too soft):

• Front fork oil level insufficient and/or front fork
• leaking oil
• Front fork oil viscosity too low
• Front fork and/or rear shock absorber spring weak
• Rear shock absorber leaking oil or gas
• Tire air pressure too low

Poor braking performance

1. Air in the brake line
2. Brake pad or disc wornBrake fluid leaking
3. Brake disc warped
4. Brake pads contaminated
5. Brake fluid deteriorated
6. Primary and/or secondary master cylinder cup(s) damaged
7. Master cylinder scratched
8. Brake maladjusted (lever or pedal play excessive)

Battery trouble

Battery discharged:

• Charge insufficient
• Battery faulty (too low terminal voltage)
• Battery cable making poor contact
• Flywheel magneto trouble
• Wiring faulty
• Regulator trouble

Battery overcharged :

• Flywheel magneto trouble
• Regulator trouble
• Battery faulty