Yamaha YZ250 2021 User Manual

FRONT FORK
4-21
(to the damper assembly “4”)
TIP
• While compressing the inner tube “5”, set the
cap bolt ring wrench “7” between the inner tube
and locknut “6”.
• Fully finger tighten the adjuster onto the damp-
er assembly.
27.Measure:
• Gap “a” between the adjuster “1” and the
locknut “2”
Out of specification  Retighten and readjust
the locknut.
TIP
If it is installed with a gap out of specification,
correct damping force cannot be obtained.
28.Tighten:
• Adjuster (damper assembly) “1”
TIP
Hold the locknut “2” and tighten the adjuster.
29.Install:
• Adjuster “1”
(to the inner tube)
30.Fill:
• Front fork leg
NOTICE
ECA24570
• Be sure to use the recommended oil. Other
oils may have an adverse effect on front
fork performance.
• When disassembling and assembling the
front fork leg, do not allow any foreign ma-
terial to enter the front fork.
Cap bolt ring wrench
90890-01501
Cap bolt ring wrench
YM-01501
Gap “a” between the adjuster and
the locknut
0.5–1.0 mm (0.02–0.04 in)
Adjuster (damper assembly)
29 N·m (2.9 kgf·m, 21 lb·ft)
1
2
a
T
R
.
.
Inner tube and adjuster
55 N·m (5.5 kgf·m, 41 lb·ft)
LOCTITE®
Recommended oil
Yamaha Suspension Oil S1
Standard oil amount
320 cm³ (10.8 US oz, 11.3 Imp.oz)
Extent of adjustment
300–365 cm³ (10.1–12.3 US oz,
10.6–12.9 Imp.oz)
T
R
.
.
1

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