2002 Yamaha YFM660 Grizzly factory service and repair manual, Page 166Get this manual
CAMSHAFT AND CYLINDER HEAD Install
the decompressor cam guide plates and camshaft sprocket bolts 0Camshaft sprocket bolt: 20 Nm (2.0 kg, 14 ft lb)
NOTE: Insert screwdriver into the timing chain tensioner hole and push the timing chain guide inward Remove
3.Install: Timing chain guide 4.Install: Timing chain tensioner Installation steps: a.Lightly press the timing chain tensioner rod into the timing chain tensioner housing by handb.While pressing the timing chain tensioner rod, wind it clockwise with thin screwdriver until it stopsc.With the screwdriver still inserted into the timing chain tensioner, install the timing chain tensioner and gasket onto the cylinder blockThen, tighten the timing chain tensioner bolts to the specified torque