Compression System - Yamaha DT125RE 2005 Service Manual

COMPRESSION SYSTEM

• Cylinder and cylinder head
• Piston and piston ring
• Crankcase and crankshaft
• Reed valve
Y.P.V.S.
• Power valve
• Control cable
• Electrical parts
TROUBLESHOOTING
PROBABLE CAUSE
• Loose spark plug
• Broken cylinder head gasket
• Broken cylinder gasket
• Loose cylinder head or cylinder
• Worn, damaged or seized cylinder
• Improperly installed piston ring
• Worn, fatigued or broken piston ring
• Seized piston ring
• Seized or damaged piston
• Improperly seated crankcase
• Improperly sealed crankcase
(Damaged oil seal)
• Seized crankshaft
• Deformed reed valve stopper
• Improperly adjusted reed valve stopper
height
• Improperly seated reed valve
• Loose intake manifold
• Broken gasket
• Broken reed valve
PROBABLE CAUSE
• Seized or damaged power valve
• Carbon buid-up
• Improperly adjustable cable
• Seized or discontinuous cable
• Faulty battery
(Improperly charged battery)
• Faulty main switch
• Faulty servomotor
• Faulty GDI unit
• Faulty Y.P.V.S. control unit
• Broken or shorted wiring
9-4
TRBL
SHTG