2007-2009 Honda TRX300EX TRX300X service manual, Page 137Get this manual
CYLINDER HEADNALVE Coat new O-rings with engine oil and install them into the valve adjuster cover groovesInstall the valve adjuster covers and tighten the bolts
Install the out-side sealing washer groove aligning the locking tab on the cvlinder head
Install the oil pipe to the cylinder head and tighten the mounting bolt securelyInstall the oil pass pipe bolt and new sealing washerTighten the oil pipe bolt to specified torque TORQUE: 14 Nm (1.4 kgfm, 10 Ibfft)