2004 Official factory service manual for Yamaha YFZ450S ATV Quad., Page 158Get this manual
CYLINDER HEAD ENG
hPut mark on the corner of the cylinder head bolt and the cylinder head as shownNOTE: Tighten the bolts 90 in each of the two steps to reach the specified angle of 180 in the proper tightening sequence as shown
Cylinder head bolts Final Specified angle 180