IAME Parilla x30 125cc RL-TaG, Инструкция по сборке и руководство пользователя

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MAN-043/B 29
3.11 SPARK PLUG AND THERMAL DEGREE
The engine is supplied with a standard
NGK BR10EG
spark plug, which represents a
good compromise between the needs of a good break-in and the racing needs in
normal conditions.
Use of different spark plugs is possible and, as a general information, we are
attaching a correspondence list among spark plug of other brands, based on
thermal
degree
which represents the capacity of the spark plug to dissipate the internal heat.
The colour of the various parts of the spark plug more exposed to the combustion
flames gives a good indication on the adequacy of the thermal degree and on the
carburetion. It is necessary though to understand which of the two parameters has to
be changed and only the experience tells how to identify the most proper thermal
degree of a spark plug as lean or rich mixtures can generate the same final look
which can also be achieved with a hot or cold spark plug.
See table:
An excessive warm spark plug shows the
symptoms, listed aside.
ATTENTION:
Always use a warmer than standard spark plug
with cold or rainy climate.
ƒ
Extremely clear colour, porous look and
calcification of the electrodes and of the internal
insulation.
ƒ
Irregularities in the ignition, preignition and
detonation with tendency to perforate the top of
the piston.
ƒ
Note: some of these symptoms can be
achieved with lean mixtures.
A correct thermal degree shows:
ƒ
Colour of the insulator end from yellow grey to
dark brown for mixtures respectively lean or rich.
An excessively cold spark plug shows the
symptoms, listed aside.
ATTENTION:
Always use a colder than standard spark plug
with hot climates.
ƒ
Insulator end and electrodes covered with black
shady soot.
ƒ
Ignition difficulties
ƒ
Note: a wet or oily electrode could also mean
an excessively rich mixture.
COMPARISON TABLE BASED ON
THE THERMAL DEGREE
HOT
BOSCH NGK CHAMPION
WO8CS BR9EG N54R
WO7CS BR10EG N52R
WO6CS BR11EG
COLD