2007-2009 Honda TRX300EX TRX300X service manual, Page 290Get this manual
HYDRAULIC DISC BRAKE Coat the master piston and piston cups with clean brake fluidInstall the spring onto the piston endDo not aIow the piston cup lips to turn inside out
Install the master pistonspring into the master cylinder
MASTER PISTON
Be certain the snap ring is firmly seated in the groove
Install the snap ring into the groove in the master cylinder
SNAP RING
TOOL: Snap ring pliers
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