Yamaha YZ250 2021 User Manual

CLUTCH
5-2
EAM30113
CHECKING THE CLUTCH BOSS
1. Check:
• Clutch boss splines
Damage/pitting/wear  Replace the clutch
boss.
TIP
Pitting on the clutch boss splines will cause er-
ratic clutch operation.
EAM30114
CHECKING THE PRESSURE PLATE
1. Check:
• Pressure plate
Crack/damage  Replace.
EAM30115
CHECKING THE PUSH LEVER SHAFT
1. Check:
• Push lever shaft
Wear/damage  Replace.
EAM30484
CHECKING THE PUSH RODS
1. Check:
• Push rod 1 “1”
• Bearing “2”
• Washer “3”
• Push rod 2 “4”
Cracks/damage/wear  Replace.
2. Measure:
• Push rod 2 bending limit
Out of specification  Replace.
EAM30117
CHECKING THE PRIMARY DRIVE GEAR
1. Check:
• Primary drive gear
Damage/wear  Replace the primary drive
and primary driven gears as a set.
Excessive noise during operation  Replace
the primary drive and primary driven gears as
a set.
2. Check:
• Primary-drive-gear-to-primary-driven-gear
free play
Free play exists  Replace the primary drive
and primary driven gears as a set.
EAM30118
CHECKING THE PRIMARY DRIVEN GEAR
1. Check:
• Primary driven gear
Damage/wear  Replace the primary drive
and primary driven gears as a set.
Excessive noise during operation  Replace
the primary drive and primary driven gears as
a set.
EAM30121
INSTALLING THE CLUTCH
1. Install:
• Push lever shaft “1”
• Copper washer “2”
• Push lever shaft bolt “3”
TIP
Apply the lithium-soap-based grease on the oil
seal lip.
G088995
Push rod bending limit
0.30 mm (0.012 in)
Push lever shaft bolt
6 N·m (0.6 kgf·m, 4.4 lb·ft)
New
T
R
.
.

Yamaha YZ250 2021 Specifications

General

Engine Type	249cc liquid-cooled 2-stroke; reed-valve inducted
Bore x Stroke	66.4mm x 72.0mm
Compression Ratio	8.9~10.6:1
Ignition	CDI
Transmission	5-speed; multiplate wet clutch
Final Drive	Chain
Suspension Rear	KYB® single shock; fully adjustable, 12.4-in travel
Brakes Front	Hydraulic disc, 270mm
Tires Front	80/100-21
Tires Rear	110/90-19
Width	32.5 in
Height	50.8 in
Wheelbase	58.5 in
Ground Clearance	14.2 in
Fuel Capacity	2.1 gal
Wet Weight	227 lb
Fuel Delivery	Keihin PWK38S carburetor
Suspension Front	KYB® Speed-Sensitive System inverted fork; fully adjustable, 11.8-in travel
Brakes Rear	Hydraulic disc, 245mm