KTM 690 Enduro R 2018, Repair Manual

Page: 167 / 311

17.4.11
Cylinder
-
Nikasil®
coating
Nikasil®
is
a
surface
protection layer
for
a
coating procedure
devel-
oped by
Mahle. The
name
is derived from the
two
materials used
in this
procedure
-
a
layer
of nickel into which is embedded the
particularly hard
silicone carbide.
The
most
important advantages
of the
Nikasil® coating
are
very
good heat
conductivity,
resulting in much
improved performance,
low
wear,
and
a
lightweight cylinder.
305656-10
17.4.12
Checking/measuring
the
cylinder
NN
—
Check the
O-ring
of the chain
adjuster
for
damage
and
wear.
OE
i
*
.
=
<<
2
If there
is
damage af
wear:
NL
ve
4
—
Change
the
O-ring.
L-
9
~
—
Check the
cylinder bearing
surface for
damage.
wa
1 oO
»
If the
cylinder bearing
surface is
damaged:
P
Se=
e
-—
Change
the
cylinder
and
piston.
re
x
—
Measure the
cylinder
diameter
at
several locations
on
a,
the
ae
and
@
axes
using
a
micrometerto
identify
oval
wear.
—
Guideline
Cylinder
-
bore
diameter
Size | 102.000
...
102.012
mm
(4.01574
...
4.01621
in)
Size Il 102.013
...
102.025
mm
(4.01625
...
4.01672 in)
—
The
cylinder
size
2
is marked
on
the side of the cylinder.
305588-10
-—
Using
a
straightedge
and the
special tool,
check the
sealing
surface of the
cylinder
head
for
distortion.
Feeler gauge (59029041100) (*—
p.
286)
Cylinder/cylinder
head
-
seal-
|
s
0.10
mm
(s
0.0039
in)
ing
area
distortion
»
If
the
measured value does not meet
specifications:
—
Change
the
cylinder.
305589-10 4
165