Yamaha YZF-R125 Service Manual: Assembling the front fork legs

Yamaha YZF-R125 Service Manual / Chassis / Front fork / Assembling the front fork legs

The following procedure applies to both of the front fork legs.

WARNING

Make sure the oil levels in both front fork legs are equal.
Uneven oil levels can result in poor handling and a loss of stability.

NOTE:

When assembling the front fork leg, be sure to replace the following parts:

Outer tube bushing
Oil seal
Dust seal
Clip

Before assembling the front fork leg, make sure all of the components are clean.

1. Install:

Damper rod

CAUTION:

Allow the damper rod to slide slowly down the inner tube until it protrudes from the bottom of the inner tube. Be careful not to damage the inner tube.

2. Lubricate:

Inner tube's outer surface

3. Tighten:

Damper rod bolt "1"

NOTE:

While holding the damper rod with the damper rod holder "2" and T-handle "3", tighten the damper rod bolt.

Assembling the front fork legs

4. Install:

Outer tube bushing "1"
Washer "2" (with the fork seal driver weight "3" and fork seal driver attachment "4")

Assembling the front fork legs

5. Install:

Oil seal "1"
(with the fork seal driver weight "2" and fork seal driver attachment "3")

CAUTION:

Make sure the numbered side of the oil seal faces up.

NOTE:

Before installing the oil seal, lubricate its lips with lithium-soap-based grease.
Lubricate the outer surface of the inner tube with fork oil.
Before installing the oil seal, cover the top of the front fork leg with a plastic bag to protect the oil seal during installation.

Assembling the front fork legs

6. Install:

Oil seal clip "1"

NOTE:

Adjust the oil seal clip so that it fits into the outer tube's groove.

Assembling the front fork legs

7. Install:

Dust seal "1"
(with the fork seal driver weight "2")

Assembling the front fork legs

8. Fill:

Front fork leg (with the specified amount of the recommended fork oil)

CAUTION:

Be sure to use the recommended fork 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 material to enter the front fork.

9. After filling the front fork leg, slowly stroke the inner tube "1" up and down (at least ten times) to distribute the fork oil.

NOTE:

Be sure to stroke the inner tube slowly because the fork oil may spurt out.

Assembling the front fork legs

10.Before measuring the fork oil level, wait ten minutes until the oil has settled and the air bubbles have dispersed.

NOTE:

Be sure to bleed the front fork leg of any residual air.

11.Measure:

Front fork leg oil level "a" (from the top of the inner tube, with the inner tube fully compressed and without the fork spring) Out of specification Correct.

12.Install:

Fork spring "1"

NOTE:

Install the spring with the smaller pitch "a" facing up.

13.Install:

O-ring
(to front fork cap)
Front fork cap
Clip

NOTE:

Before installing the front fork cap, lubricate its O-ring with grease.
Insert the front fork cap into the inner tube, and then install the clip, making sure that the cap is securely held in place with the clip.

Checking the front fork legs

The following procedure applies to both of the front fork legs. 1. Check: Inner tube Outer tube Bends/damage/scratches Replace. WARNINGDo not attempt to straighten a bent inner ...

Installing the front fork legs

The following procedure applies to both of the front fork legs. 1. Install: Front fork leg Temporarily tighten the upper and lower bracket pinch bolts. NOTE: Make sure the inner tube end ...

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