Check the colour of the ceramic insulation around the central electrode: an even, light brown colour indicates the engine is in good condition and running at the right temperature.
Inspect the centre electrode for wear and check spark plug gap, which should be: 0.8+/-0.1 Mm.

Important
Check the gap between the central and side electrodes. Replace the spark plug if taken value is different from the specified one or the spark plug shows clear signs of carbon settling.
Important
Do not use spark plugs with inadequate thermal rating or incorrect thread length.
The spark plug must be securely installed.
If a spark plug is loose, it can overheat and damage the engine.
Spark plug type
Make: ngk
Type: mar9a-j


Remove the coil-spark plugs wires (1), loosening the screws (2) of both spark plugs.
Using the appropriate tool 88713.2877 To replace the spark plugs.


Place the coil-spark plugs wires (1) in the relevant seats and tighten the screws (2) to a torque of 10 nm (min. 9 Nm - max. 11 Nm) (sect. 3 - 3, Engine torque settings).



Checking valve clearances
Changing and cleaning the air filtersRefitting the side stand
Place the stand plate on the rear shock absorber support; bring adjuster (14)
in line with bracket (s) and start the screw
(12) in the nut behind the bracket (s).
Insert the screws (11), (3) and (10) fully home in this order, but do not
tighten.
Loosen the screw (12) with the relative nut ...
Overhaul of cylinder head components
Cylinder heads
Remove any carbon deposits from the combustion chamber and its ducts.
Remove any scale from the coolant ducts.
Check for cracking and inspect the sealing surfaces for scoring, ridges or other
damage.
Check that the cylinder barrel mating surfaces of the cylinder head are ...
Removal of the control unit
Loosen the screws (1) and remove the relay supporting bracket (2), disconnect
the connectors (3) and remove the control
unit (4) from the vehicle.
...