2003-2006 Kawasaki KFX400 service manual, Page 105Get this manual
Install the valve spring retainer by pressing down the spring using the valve lifterFit the cotter halves to the stem end and release the lifter to allow the cotter to wedge between the retainer and the valve stemMake sure that the rounded lip of the cotter fits snugly into the groove in the stem end09916-14510: Valve spring compressor 09916-14910: Attachment 09916-84511: Tweezers