Yamaha TDM850 User Manual page 53

2*14 Engine, clutch and transmission
8.9 Unscrew and remove the camshaft holder bolts (arrowed)
8.10b ... and remove the shim either from inside the follower...
locations are readily identifiable by the differing
number or location of bolts which secures each
one.
9 Before slackening the camshaft holder bolts,
check whether any of the cam lobes are directly
depressing the valves and if so, rotate the
camshaft slightly to release the pressure; this will
prevent distortion or undue strain on the holders
as the bolts are slackened. Unscrew the
camshaft holder boits for the camshaft being
worked on, evenly and a little at a time in a criss-
cross
8.11 Check the journal surfaces of the
camshaft for scratches or wear
pattern, until they are all loose (see
illustration).
Caution: If the bolts aren't loosened
evenly, the camshaft may bind.
Remove the bolts, then lift off the camshaft
holders, noting how they fit, and remove the
camshafts (see illustrations 8.26a and 8.25).
Retrieve the dowels from either the holder or the
cylinder head if they are loose. Keep all mated
parts together.
10 Obtain a container which is divided into ten
compartments, and label each compartment
8.12a Check the lobes of the camshaft for
wear - here's an example of damage
requiring camshaft repair or renewal
8.10a Lift out the follower ...
8.10c ... or from the top of the valve
with the location of its corresponding valve in the
cylinder head and whether it belongs with an inlet
or an exhaust valve. If a container is not
available, use labelled plastic bags. Using a pair
of pliers or a magnet if necessary, lift each
follower out of the cylinder head and store it in its
corresponding compartment in the container (see
illustration). The shim is likely to stick to the
inside of the follower so take great care not to
lose it when removing the follower
illustration). Retrieve the shim from either the
inside of the follower or pick it out of the top of
the valve using a magnet, a small screwdriver
with a dab of grease on it (the shim will stick to
the grease), or a screwdriver and a pair of pliers
(see illustration). Do not allow the shim to fall
into the engine.
Inspection
11 Inspect the bearing surfaces of the camshaft
holders and the corresponding journals on the
camshaft. Look for score marks, deep scratches
and evidence of spailing (a pitted appearance)
(see illustration).
12 Check the camshaft
discoloration (blue appearance), score marks,
chipped areas, flat spots and spailing (see
illustration). Measure the height of each lobe
UNREGISTERED VI
(see
lobes for heat
Staged by Stalker
UNREGISTERED VERSION OF PICTURE-DESK