Honda TRX680FA Service Manual page 219

CYLINDER HEAD/VALVE/CAMSHAFT
Carefully rotate the
crankshaft while
holding the cam
chain to avoid jam-
ming the cam chain
against the timing
sprocket of the
crankshaft.
Check the decompressor cam operation.
Press on the decompressor cam as shown.
As you press on one side, the decompressor cam
should lock above the base of the exhaust cam lobe.
As you press on other side, the decompressor cam
lobe should extend below the base of the exhaust
cam lobe.
Push
Push
DECOMPRESSOR CAM
INSTALLATION
Turn the crankshaft clockwise using the recoil
starter and align the "T" mark on the flywheel with
the index notch in the crankcase cover.
Retract the tensioner lifter shaft and secure it with
the stopper tool (page 9-16).
INDEX NOTCH
"T" MARK
Install the dowel pins if they are removed.
Install the camshaft holder B onto the camshaft
assembly.
DOWEL PINS
HOLDER B
Before installing the
camshaft, be sure
the cylinder bolt
(under the cam
shaft) is tightened
securely (page 10-
9).
Lubricate the camshaft bearings and cam chain with
engine oil.
Install the camshaft holder plate onto the camshaft
holders, aligning the holes with the dowel pins.
Place the camshaft assembly onto the cylinder and
install the cam chain over the sprocket while align-
ing the timing marks (index lines) on the sprocket
with the cylinder top surface and holder plate edge.
Locate the dowel pins into the holes in the cylinder
securely.
Be sure the timing marks lines up with the cylinder
top surface and holder plate edge.
9-17