If they show any damage, replace it.

Caliper Fluid Seal Damage
Caliper Piston and Cylinder DamageSteering 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 ...
Oil Seal, Grease Seal
Do not remove pressed oil or grease seals unless removal
is necessary. Replace with new ones whenever removed.
Press new oil seals with manufacture and size marks facing
out. Make sure the seal is aligned properly when installing.
Apply specified grease to the lip of seal before installing ...
Fuels Containing Oxygenates
Gasoline frequently contains oxygenates
(alcohols and ethers) especially
in areas of the U.S. and Canada
which are required to sell such reformulated
fuels as part of a strategy to
reduce exhaust emissions.
The types and volume of fuel oxygenates
approved for use in unleaded
gasoline by th ...