2007-2009 Honda TRX300EX TRX300X service manual, Page 131Get this manual
CYLINDER HEADVALVE To prevent 1055 of Install the valve spring cotters using the valve tension, do not spring compressorcompress the valve springs more than TOOl: 07757-0010000 necessaryValve spring compressor
Support the cylinder head so the valve heads will not contact anything that cause damage
Tap the valve stems gently with two plastic hammers to seat the cotters firmlyInstall the cylinder head (page 7-21)