If any is worn down to the service limit, replace the brush assy.
Starter Motor Brush Length [B] Standard: 12.05 mm (0.4744 in.) Service Limit: 6.55 mm (0.258 in.)

Starter Motor Assembly
Commutator Cleaning and InspectionCamshaft Chain Tensioner Installation
Replace the O-ring [A] with a new one.
Apply grease to the new O-ring.
Release the stopper [B] and push the push rod [C] into the
interior of the tensioner body [D] so that the position of the
push rod is 3 or 4 notches [E] as shown in the figure.
Install the tensioner body so that the ...
Rear Brake Pad Installation
Check that the pad spring is in place on the caliper.
Push the caliper piston in as far as it will go.
Install the piston side pad [A] first, and then another pad.
Fit the brake pad end into the recess [B] of the caliper
holder.
Install the pad pin and the plug.
Tighten:
Torque - ...
Connecting Rod Big End
Bearing Insert/Crankpin Wear Inspection
Remove the connecting rod big end (see Connecting Rod
Removal).
Cut strips of plastigage to crankpin width. Place a strip
on the crankpin parallel to the crankshaft installed in the
correct position.
Tighten the connecting rod big end nuts to the specified
torque (see Connecting Rod I ...