2003 Yamaha YFM400FAR Kodiak Factory Service Manual, Page 137Get this manual
CYLINDER HEAD
NOTE: Be sure the "I" mark on the camshaft sprocket is aligned with the match mark on the cylinder headG Force
the camshaft clockwise and counterclockwise to remove timing chain slackG Insert screwdriver into the timing chain tensioner hole and push the timing chain guide inwardG While pushing the timing chain guide, be sure that the camshaft sprocket "I" mark is aligned with the cylinder head match mark 2G If the marks are aligned, tighten the camshaft sprocket boltIf the marks are not aligned, change the meshing position of the camshaft sprocket and timing chain