Kawasaki Ninja Service Manual: Front Fork Oil Change

• Remove the front fork (see Front Fork Removal (Each Fork Leg)).
• Turn the spring preload adjuster fully counterclockwise for removing the piston rod assy easily.
• Hold the inner tube lower end in a vise.
• Using the wrench [A], unscrew the top plug [B] out of the outer tube.

  Special Tool - Top Plug Wrench (45 mm): 57001-1741

• Holding the piston rod nut with a wrench [A], remove the top plug [B] from the piston rod.

  Special Tool - Top Plug Wrench (45 mm): 57001-1741

• Remove: Rebound Damping Adjuster Rod (Inside) [A] Compression Damping Adjuster Rod (Outside) [B] Piston Rod Nut [C]

• Using the rod guide case wrench [A], remove the piston rod guide case from the inner tube.

Special Tool - Rod Guide Case Wrench, 35 mm: 57001 -1758

NOTICE

A socket of piston rod guide case is shallow (4 mm) and therefore be sure to check that the wrench (Special Tool: 57001-1758) is securely seated on the piston rod guide case.

When loosening the piston rod guide case. If the wrench is not securely seated on it, the piston rod guide case may brake.

• Remove: Piston Rod Assy [A] Collar [B] Fork Spring [C] Fork Spring Guide [D]

• Drain the fork oil into a suitable container [A].

Pump the inner tube up and down at least ten times to expel the oil from the fork.

• Install: Collar [A] Fork Spring [B] Fork Spring Guide [C]

• Hold the fork tube upright, press the outer tube.
• Pour in the type and amount of fork oil specified.

Pour the fork oil until the upper of the inner tube hole [A].

Fork Oil Recommended Oil: SHOWA SS-19: 44091-0009 Amount (Per Side): When changing oil: Approx. 420 mL (14.2 US oz.) After disassembly and completely dry (Total): 495 ±2.5 mL (16.7 ±0.085 US oz.)

• Move the inner tube up and down more than ten times in order to expel the air from the fork oil.
• Insert the piston rod assy into the inner tube.

NOTE

Lifting the outer tube, and insert the piston rod assy.

NOTICE

When inserting, be careful not to damage the piston ring [A].

• Hold the inner tube bottom by a vise.
• Using rod guide case wrench [A], tighten the piston rod guide case to the inner tube.

Special Tool - Rod Guide Case Wrench, 35 mm: 57001 -1758

Torque - Piston Rod Guide Case: 90 N·m(9.2 kgf·m, 66 ft·lb)

NOTE

• The tightening torque of the piston rod guide case is specified to 90 N·m (9.2 kgf·m, 66 ft·lb), however in use of the rod guide case wrench (special tool: 57001-1758) [A] you reduce the torque to about 93% of the specified value [84 N·m (8.6 kgf·m, 62 ft·lb)] due to the offset [B] of the wrench square hole.
• This torque value [84 N·m (8.6 kgf·m, 62 ft·lb)] is applicable when you use a wrench whose length [C] gives leverage of approximately 450 mm (17.7 in.) between the grip point to the center of the coupling square.
• To obtain the correct tightening torque with your torque wrench, you need to calculate as follows.

Formula: a × b ÷ (b + c) = d

[a] Specified torque

[b] Length from center of square hole to grip point

[c] Offset = 30 mm

[d] Tightening torque

For an example: 90 N·m × 450 ÷ (450 + 30) = 84 N·m

NOTICE

A socket of piston rod guide case is shallow (4 mm) and therefore be sure to check that the wrench (Special Tool: 57001-1758) is securely seated on the piston rod guide case.

When tightening the piston rod guide case. If the wrench is not securely seated on it, the piston rod guide case may brake.

• Install the piston rod nut [A] until it is bottomed.
• Install: Compression Damping Adjuster Rod (Outside) [B] Rebound Damping Adjuster Rod (Inside) [C]

• Replace the O-ring [A] with a new one.
• Apply grease to the new O-ring.
• Install the top plug [B] to the piston rod.
• Holding the top plug with the wrench [C], tighten the piston rod nut against the top plug.

  Special Tool - Top Plug Wrench (45 mm): 57001-1741

• Pour the fork oil of the remainder until the upper [A] of the piston rod guide case [B].
• Move the piston rod assembly up and down more than 10 times in order to expel all the air from the fork oil.
• Move the outer tube up and down more than 10 times in order to expel all the air from the fork oil.

• Measure the oil level as follows.

Hold the inner tube vertically in a vise.

Wait until the oil level settles.

With the fork fully compressed, insert a tape measure or rod into the piston rod guide case [A], and measure the distance [B] from the top [C] of the outer tube [D] to the oil.

Fork Oil Level (fully compressed) Standard: 85 ±2 mm (3.35 ±0.08 in.)

NOTE

• After more than 10 minutes, oil level is 76 ±2 mm (2.99 ±0.08 in.).
• Fork oil level may also be measured using the fork oil level gauge [E].

Special Tool - Fork Oil Level Gauge: 57001-1290

Pull the handle slowly to pump out the excess oil until the oil no longer comes out.

If no oil is pumped out, there is insufficient oil in the inner tube. Pour in enough oil, then pump out the excess oil as shown above.

• Lift the outer tube.
• Using the wrench, tighten the top plug temporary.

  Special Tool - Top Plug Wrench (45 mm): 57001-1741

• Install the front fork (see Front Fork Installation (Each Fork Leg)).

NOTE

After installing the front fork, adjust the spring preload and damping force correctly.