Yamaha MX175 Owner's Manual page 52

Troubleshooting
46
3. Check the spark plug.
WARNING
• To prevent FIRE HAZARDS be sure fuel is not
present in the spark plug area.
• To prevent FIRE HAZARDS be sure to place the
spark plug as far away as possible from the
spark plug hole and carburetor area.
• To prevent ELECTRIC SHOCK do not hold spark
plug lead with hand while testing.
a.
Turn the engine switch to "
b.
Check the spark plug for spark strength.
c.
Clean the spark plug if it has excessive carbon
deposits.
d. Check the spark plug gap, and adjust it if it is
incorrect.
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
e.
Replace the spark plug if it still does not spark.
Standard spark plug:
BPR4ES (NGK)
Spark plug tightening torque:
20 N·m (2.0 kgf·m, 15 lb·ft)
4. Check the fuel system.
" (START).