Yamaha YZ250 2021, Owner'S Manual

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FRONT FORK
4-15
5. Remove:
• Base valve “1”
(from the damper assembly)
TIP
Hold the damper assembly with the cap bolt ring
wrench “2” and use the cap bolt wrench “3” to re-
move the base valve.
EAM30057
CHECKING THE FRONT FORK LEGS
1. Check:
• Inner tube surface
Scratches

Repair or replace.
Use #1000 grit wet sandpaper.
Damaged oil lock piece

Replace.
• Inner tube bends
Out of specification

Replace.
Use the dial gauge.
TIP
The bending value is shown by one half of the
dial gauge reading.
WARNING
EWA13650
Do not attempt to straighten a bent inner
tube as this may dangerously weaken it.
2. Check:
•
Outer tube
Scratches/wear/damage

Replace.
3. Measure:
• Fork spring free length “a”
Out of specification

Replace.
4. Check:
•
Damper assembly “1”
Bend/damage

Replace.
•
O-ring “2”
Wear/damage

Replace.
NOTICE
ECA14200
• The front fork leg has a built-in damper ad-
justing rod and a very sophisticated inter-
nal construction, which are particularly
sensitive to foreign material.
• When disassembling and assembling the
front fork leg, do not allow any foreign ma-
terial to enter the front fork.
5. Check:
• Base valve “1”
Wear/damage

Replace.
Cap bolt wrench
90890-01500
Cap bolt wrench
YM-01500
Cap bolt ring wrench
90890-01501
Cap bolt ring wrench
YM-01501
Inner tube bending limit
0.2 mm (0.01 in)
1
2
3
Fork spring free length limit
449.0 mm (17.68 in)
G088921
2
1