TROUBLESHOOTING
9-1
EAS28450
TROUBLESHOOTING
EAS28460
GENERAL INFORMATION
TIP
The following guide for troubleshooting does not
cover all the possible causes of trouble. It should
be helpful, however, as a guide to basic trouble-
shooting. Refer to the relative procedure in this
manual for checks, adjustments, and replace-
ment of parts.
EAS28480
STARTING FAILURE/HARD STARTING
Engine
1. Cylinder and cylinder head
• Loose spark plug
• Loose cylinder head or cylinder
• Damaged cylinder head gasket
• Damaged cylinder gasket
• Worn or damaged cylinder
• Incorrect valve clearance
• Improperly sealed valve
• Incorrect valve-to-valve-seat contact
• Incorrect valve timing
• Faulty valve spring
• Seized valve
2. Piston and piston ring(s)
• Improperly installed piston ring
• Damaged, worn or fatigued piston ring
• Seized piston ring
• Seized or damaged piston
3. Air filter
• Improperly installed air filter
• Clogged air filter element
4. Crankcase and crankshaft
• Improperly assembled crankcase
• Seized crankshaft
Fuel system
1. Fuel tank
• Empty fuel tank
• Clogged fuel tank cap breather hole
• Deteriorated or contaminated fuel
• Clogged or damaged fuel hose
2. Fuel pump
• Faulty fuel pump
• Clogged fuel pump filter
• Faulty fuel pump relay (for YP125RA)
3. Throttle body
• Deteriorated or contaminated fuel
• Sucked-in air
Electrical system
1. Battery
• Discharged battery
• Faulty battery
2. Fuse(s)
• Blown, damaged or incorrect fuse
• Improperly installed fuse
3. Spark plug
• Incorrect spark plug gap
• Incorrect spark plug heat range
• Fouled spark plug
• Worn or damaged electrode
• Worn or damaged insulator
• Faulty spark plug cap
4. Ignition coil
• Cracked or broken ignition coil body
• Broken or shorted primary or secondary coils
• Faulty spark plug lead
5. Ignition system
• Faulty ECU
• Faulty crankshaft position sensor
• Broken generator rotor woodruff key
6. Switches and wiring
• Faulty main switch
• Broken or shorted wiring
• Faulty front, rear or both brake light switches
• Faulty start switch
• Faulty sidestand switch
• Improperly grounded circuit
• Loose connections
7. Starting system
• Faulty starter motor
• Faulty starter relay
• Faulty starting circuit cut-off relay
• Faulty starter clutch
EAS28500
INCORRECT ENGINE IDLING SPEED
Engine
1. Cylinder and cylinder head
• Incorrect valve clearance
• Damaged valve train components
2. Air filter
• Clogged air filter element
Fuel system
1. Throttle body
• Damaged or loose throttle body joint
• Improperly adjusted engine idling speed
• Improper throttle grip free play
Summary of Contents for MBK XMAX 2014
Page 1: ...2014 SERVICE MANUAL YP125R YP125RA 2DM F8197 E0 ...
Page 6: ......
Page 8: ......
Page 64: ...TIGHTENING TORQUES 2 17 Muffler tightening sequence 1 2 3 ...
Page 72: ...LUBRICATION SYSTEM DIAGRAMS 2 25 EAS2DM1116 LUBRICATION SYSTEM DIAGRAMS 1 2 3 4 5 3 ...
Page 78: ...CABLE ROUTING 2 31 Steering head front view 1 2 3 4 5 6 8 8 A 7 7 ...
Page 80: ...CABLE ROUTING 2 33 Front brake left side view for YP125R 1 2 2 1 1 2 2 D E A B C ...
Page 82: ...CABLE ROUTING 2 35 Front brake left side view for YP125RA 2 1 1 2 1 2 2 A B D E C ...
Page 92: ...CABLE ROUTING 2 45 Frame right side view 3 2 4 1 2 3 A B 6 5 3 A B 3 3 2 3 3 A A B A B B 3 ...
Page 94: ...CABLE ROUTING 2 47 Engine right side view 6 6 6 6 C D C D D C 10 B 9 5 6 1 2 8 3 4 5 6 7 A ...
Page 98: ...CABLE ROUTING 2 51 Frame left side view C D C D 2 1 E 1 2 D C 6 1 4 5 3 2 1 7 3 2 1 A B ...
Page 100: ...CABLE ROUTING 2 53 Engine left side view 1 1 1 1 1 2 3 4 5 6 7 8 9 7 7 A B A B A B 1 ...
Page 106: ...CABLE ROUTING 2 59 Rear brake right side view 2 2 2 2 2 2 1 1 2 3 A B C 3 ...
Page 110: ...CABLE ROUTING 2 63 ...
Page 228: ...REAR SHOCK ABSORBER ASSEMBLIES AND SWINGARM 4 89 ...
Page 231: ......
Page 291: ...CRANKSHAFT 5 60 a 1 ...
Page 292: ...CRANKSHAFT 5 61 ...
Page 302: ...WATER PUMP 6 9 ...
Page 313: ......
Page 331: ...CHARGING SYSTEM 8 18 ...
Page 349: ...COOLING SYSTEM 8 36 ...
Page 391: ...FUEL PUMP SYSTEM 8 78 ...
Page 400: ...IMMOBILIZER SYSTEM 8 87 a Light on b Light off ...
Page 401: ...IMMOBILIZER SYSTEM 8 88 ...
Page 405: ...ABS ANTI LOCK BRAKE SYSTEM for YP125RA 8 92 ...
Page 439: ...ABS ANTI LOCK BRAKE SYSTEM for YP125RA 8 126 ...
Page 464: ...ELECTRICAL COMPONENTS 8 151 ...
Page 476: ......
Page 477: ......
Page 478: ......