If any one of the parts is damaged, replace the mechanical seal as a unit.
Rubber Seal [A] Mechanical Seal [B]

Water Pump Housing Assembly
RadiatorSwingarm Bearing Installation
Replace the needle bearings, ball bearing, grease seals
and circlip with new ones.
Install the needle bearings, ball bearing, grease seals and
circlip as shown in the figure.
Insert the needle bearing driver [A] into the needle bearing
[B] and press the needle bearing into the housing u ...
Air Suction Valve Installation
Install the air suction valve so that opening [A] of the reed
faces downward.
Apply a non-permanent locking agent to the threads of
the air suction valve cover bolts [A], and tighten them.
Torque - Air Suction Valve Cover Bolts: 9.8 N·m (1.0 kgf·m,
87 in·lb)
...
Steering Stem Bearing Lubrication
Remove the steering stem (see Stem, Stem Bearing Removal
in the Steering chapter).
Using a high flash-point solvent, wash the upper and
lower ball bearings [A] in the cages.
Wipe the upper and lower outer races which are press
-fitted into the head pipe to clean off grease and dirt.
V ...