Yamaha YZ450FX 2019 Owner's Service Manual page 119

Spring preload adjusting positions
Minimum
Position in which the spring is
turned in 1.5 mm (0.06 in) from
its free length.
Standard
Position in which the spring is
turned in 6.0 mm (0.24 in) from
its free length.
Maximum
Position in which the spring is
turned in 18.0 mm (0.71 in) from
its free length.
TIP
• Be sure to remove all dirt and mud from around
the locknut and adjusting ring before adjust-
ment.
• The length of the spring (installed) changes 1.5
mm (0.06 in) per turn of the adjusting ring.
b b
e. Tighten the locknut.
Locknut
10 N·m (1.0 kgf·m, 7.4 lb·ft)
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3. Install:
• Rear frame
Refer to "REAR SHOCK ABSORBER AS-
SEMBLY" on page 4-55.
Rebound damping
ECA24370
NOTICE
Do not turn the adjuster forcibly beyond its
adjusting range.
1. Adjust:
• Rebound damping
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Turn the adjuster "1" in the direction of "a" or
"b" to make an adjustment.
Direction "a"
Rebound damping is increased (sus-
pension is harder).
Direction "b"
Rebound damping is decreased (sus-
pension is softer).
* With the adjusting screw fully turned in di-
rection "a"
c c
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Compression damping (for fast compres-
sion damping)
ECA24370
NOTICE
Do not turn the adjuster forcibly beyond its
adjusting range.
1. Adjust:
• Compression damping (for fast compression
damping)
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Turn the adjuster "1" in the direction of "a" or
"b" to make an adjustment.
Direction "a"
Compression damping is increased
(suspension is harder).
Direction "b"
Compression damping is decreased
(suspension is softer).
3-31
CHASSIS
Rebound damping
Minimum (soft)
30 click(s) in direction "b"*
Standard
11 click(s) in direction "b"*
Maximum (hard)
0 click(s) in direction "a"
a
b
1