Checking The Spark Plug; Transmission Oil - Yamaha TZR50 Owner's Manual

PERIODIC MAINTENANCE AND MINOR REPAIR

Checking the spark plug

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1. Spark plug
The spark plug is an important engine
component, which should be chec-
6
ked periodically, preferably by a
Yamaha dealer. Since heat and depo-
sits will cause any spark plug to
slowly erode, it should be removed
and checked in accordance with the
periodic maintenance and lubrication
chart. In addition, the condition of the
spark plug can reveal the condition of
the engine.
The porcelain insulator around the
center electrode of the spark plug
should be a medium-to-light tan (the
ideal color when the vehicle is ridden
EAU19620 normally). If the spark plug shows a
distinctly different color, the engine
could be defective. Do not attempt to
diagnose such problems yourself.
Instead, have a Yamaha dealer check
the vehicle.
If the spark plug shows signs of elec-
trode erosion and excessive carbon
or other deposits, it should be repla-
ced.
Specified spark plug:
BR9ES (NGK)
Before installing a spark plug, the
spark plug gap should be measured
with a wire thickness gauge and, if
necessary, adjusted to specification.
Spark plug gap:
0,6 ~ 0,7 mm (0,023~0,027 in)
Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the
spark plug threads.
NOTE:
If a torque wrench is not available
when installing a spark plug, a good
estimate of the correct torque is
1/4~1/2 turn past finger tight. Howe-
ver, the spark plug should be tighte-
ned to the specified torque as soon
as possible.

Transmission oil

1. Oil level check bolt
2. Oil drain bolt
3. Oil filler cap
6-6
Tightening torque:
Spark plug:
20 Nm (2,0 m•kgf)
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EAUM1270
3
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