Honda CB HORNET 160R 2015 Shop Manual page 254

BRAKE SYSTEM
Remove the screw and brake light switch.
Remove the boot.
Remove the snap ring from the master cylinder body using
snap ring pliers.
Remove the master piston and spring from the master
cylinder.
Clean the inside of the master cylinder and master piston
with clean brake fluid.
14-10
BRAKE LIGHT SWITCH
SCREW
BOOT
MASTER CYLINDER
SPRING
MASTER PISTON
MASTER CYLINDER
SNAP RING
MASTER PISTON