Faulty Gear Shifting; Hard Shifting; Shift Pedal Does Not Move; Jumps Out Gear - Yamaha YFZ450S 2003 Service Manual

EBS00541

FAULTY GEAR SHIFTING

HARD SHIFTING

Refer to "CLUTCH DRAGGING".

SHIFT PEDAL DOES NOT MOVE

Shift shaft
• Bent shift shaft
Shift drum and shift forks
• Groove jammed with impurities
• Seized shift fork
• Bent shift fork guide bar

JUMPS OUT GEAR

Shift shaft
• Improperly adjusted shift lever position
• Improperly returned stopper lever
Shift forks
• Worn shift fork
EBS00545

CLUTCH SLIPPING/DRAGGING

CLUTCH SLIPPING

Clutch
• Loose clutch spring
• Fatigued clutch spring
• Worn friction plate
• Worn clutch plate
• Incorrectly assembled clutch

CLUTCH DRAGGING

Clutch
• Warped pressure plate
• Unevenly tensioned clutch springs
• Loose clutch boss nut
• Burnt primary driven gear bushing
• Bent clutch plate
• Swollen friction plate
• Broken clutch boss
FAULTY GEAR SHIFTING/
CLUTCH SLIPPING/DRAGGING
Transmission
Shift guide
Shift drum
Transmission
Engine oil
Engine oil
9 - 3
• Seized transmission gear
• Jammed impurities
• Incorrectly assembled transmission
• Broken shift guide
• Improper thrust play
• Worn shift drum groove
• Worn gear dog
• Low oil level
• Improper quality (low viscosity)
• Deterioration
• High oil level
• Improper quality (high viscosity)
• Deterioration
TRBL
SHTG