APRILIA TUONO 1000 - 2006 Manual page 120

NOTE
The vehicle is equipped with one
spark plug for each cylinder.
The following operations refers to the
spark plug installed in one cylinder only,
but applies to the spark plugs of both
cylinders.
TO REMOVE THE SPARK PLUG
CAUTION
Never disconnect the spark plug cap
with the engine running, since this can
cause electric shock from the ignition
system.
Do not reverse the position of the two
spark plug caps.
Do not remove the two spark plug caps
at the same time.
Remove the spark plug cap (1).
WARNING
During this operation, always wear
goggles which provide your eyes with
360° protection. Be very careful using
compressed air jets, they can cause
serious personal injury if directed
towards your body.
Using compressed air, blow all the dirt
away from the base of the spark plug.
NOTE
Use the special wrenches from
the tool kit, see page 45 (GLOVE/TOOL
KIT COMPARTMENT).
120 use and maintenance TUONO 1000
7
9
Place the special spark plug socket wrench
(2) completely over the spark plug (3).
Place the 11–13 mm open-end wrench (4)
over the hexagonal seat of the special
spark plug wrench (2).
Make sure that no dirt falls into the
cylinder through the spark plug hole.
Unscrew the spark plug and extract it from
its seat.
TO CHECK AND CLEAN THE SPARK
PLUG
This vehicle is fitted with spark plugs
featuring platinum-type electrodes.
When cleaning, do not use wire brushes
and/or abrasive products. Use a jet of
compressed air only.
Key:
5) center electrode;
6) ceramic nose;
USA
10
12
5
8 11
6
CAUTION
CAUTION
7) side electrode.
Inspect the spark plug, and make sure that
there are neither carbon deposits, nor
corrosion marks on the electrodes (5) and (7)
and on the ceramic nose (6); if necessary,
clean them with a jet of compressed air.
If the spark plug ceramic nose is cracked, or if
the electrodes are corroded, or there are
excessive deposits on the electrodes of the
nose, or the tip (8) of the central electrode (5)
is rounded, the spark plug must be replaced.
CAUTION
When replacing a spark plug, always
check the pitch (9) and length (10) of the
thread.
The use of a spark plug with too short a
threaded portion will result in carbon
deposits building up on the internal thread
of the head. This can result in damage to
the engine when the appropriate spark
plug is installed.
The use of the spark plug with too long a
threaded portion can cause the plug to
strike the piston, with consequent
irreparable damage.
Use only the recommended spark plug
type, see page 137 (TECHNICAL DATA).
Failure to observe this caution will result in
reduction in the service life and
performance of the engine.
Use a round wire feeler gauge (11) to
check the spark plug gap, in order to avoid
damaging the platinum coating.
Using a round wire feeler gauge (11), check
the spark plug gap.