2007-2009 Honda TRX300EX TRX300X service manual, Page 268Get this manual
REAR WHEELSUSPENSION Coat new O-ring with engine oil and install it into the groove in the brake disc flange
Apply grease to the rear axle splinesInstall the brake disc flange onto the axle
Install the brake disc to the brake disc flangeTighten the brake disc nuts to the specified torqueTORQUE: 26 Nm (2.7 kgfm, 20 Ibfft)