Checking The Spark Plug - Yamaha JOGR JOGRR CS50 Owner's Manual

Panel A
To remove the panel
1. Open the storage compartment.
(See page 3-11).
2. Remove the screw, and then take
the panel off.
1
2
1. Screw
2. Panel A
To install the panel
1. Place the panel in the original
position, and then install the
screw.
2. Close the storage compartment.
PERIODIC MAINTENANCE AND ADJUSTMENT
EAUM1250

Checking the spark plug

The spark plug is an important engine
component, which should be chec-
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
normally). If the spark plug shows a
distinctly different color, the engine
could be operating improperly. 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.
EAU19622
Before installing a spark plug, the
spark plug gap should be measured
with a wire thickness gauge and, if
necessary, adjusted to specification.
ZAUM0037
1. Spark plug gap
Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the
spark plug threads.
6-6
Specified spark plug:
NBR8HS/NGK (for CS50 CS50Z)
BPR4HS/NGK (for CS50M)
1
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
6