Spark Plug Inspection - Yamaha Virago XV1100L Owner's Manual

PERIODIC
MAINTENANCE
AND
MINOR REPAIR
a.
Spark
plug
gap
EAU00496
Spark
plug inspection
The
spark plug
is
an
important
engine
component and
is
easy
to inspect.
The
condition of
the spark plug
can
indicate
the condition
of
the engine.
Normally,
all
spark plugs from the
same
engine should
have
the
same
color
on
the white insulator
around
the
center electrode.
The
ideal
color
at this
point
is
a
medium-to-light tan color
for
a
motorcycle
that
is
being ridden normal-
ly.
If
one
spark plug
shows a
distinctly
different color,
there could
be some-
thing
wrong
with
the engine.
Do
not
attempt
to
diagnose such
prob-
lems
yourself. Instead,
take the motor-
cycle
to
a
Yamaha
dealer.
You
should
periodically
remove and
inspect the
spark plugs
because
heat
and
deposits
will
cause any
spark plug
to
slowly
break
down
and
erode.
If
electrode
ero-
sion
becomes
excessive, or
if
carbon
and
other deposits are excessive,
you
should replace
the
spark plug
with the
specified plug.
Specified
spark
plug:
BPR7ES
(NGK)
or
W22EPR-U
(DENSO)
Before
installing
any
spark
plug,
mea-
sure the electrode
gap
with
a
wire
thickness
gauge.
Adjust the
gap
to
specification.
Spark
plug gap:
0.7 ~ 0.8
mm
(0.028 ~ 0.031
in)
When
installing
the spark
plug,
always
clean the gasket surface
and use a
new
gasket.
Wipe
off
any grime from
the threads
and
tighten the spark
plug
to
the specified torque.
Tightening torque:
Spark
plug:
20
Nm
(2.0 rrvkg,
14.5 fMb)
NOTE:
If
a
torque
wrench
is
not available
when
you
are
installing
a spark
plug,
a good
estimate
of
the
correct
torque
is
1/4 to
1/2 turn
past
finger
tight.
Have
the
spark plug tightened
to
the
specified
torque as
soon
as
possible.
6-7