spark plugs replace YAMAHA XVS250 2004 Owners Manual

PERIODIC MAINTENANCE AND MINOR REPAIR
6-2
6
EAU17701
Periodic maintenance and lubrication chart NOTE:

The annual checks must be performed every year, except if a kilometer-based maintenance is performed in-
stead.


From 50000 km, repeat the maintenance intervals starting from 10000 km.


Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools, data and technicalskills.
NO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING (× 1000 km)
ANNUAL
CHECK
1 10203040
1*Fuel lineCheck fuel and vacuum hoses for cracks or damage.√√√√ √
2 Spark plugsCheck condition.
Clean and regap.√ √
Replace.√ √
3*ValvesCheck valve clearance.
Adjust.√ √ √ √
4 Air filter elementClean.√ √
Replace.√ √
5ClutchCheck operation.
Adjust.√ √ √ √ √
6*Front brakeCheck operation, fluid level and vehicle for fluid leakage.√√√√√ √
Replace brake pads. Whenever worn to the limit
7*Rear brakeCheck operation and adjust brake pedal free play.√ √ √ √ √ √
Replace brake shoes. Whenever worn to the limit
8*Brake hoseCheck for cracks or damage.√√√√ √
Replace. Every 4 years
5KRE2.book Page 2 Monday, June 23, 2003 3:32 PM

PERIODIC MAINTENANCE AND MINOR REPAIR
6-7
6To check the spark plugs
1. Check that the porcelain insulator
around the center electrode on
each spark plug is a medium-to-
light tan (the ideal color when the
vehicle is ridden normally).
2. Check that all spark plugs installed
in the engine have the same color.
NOTE:If any spark plug shows a distinctly dif-
ferent color, the engine could be defec-
tive. Do not attempt to diagnose such
problems yourself. Instead, have aYamaha dealer check the vehicle.3. Check each spark plug for elec-
trode erosion and excessive car-
bon or other deposits, and replace
it if necessary.
To install a spark plug
1. Measure the spark plug gap with a
wire thickness gauge and, if nec-
essary, adjust the gap to specifica-
tion.2. Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the
spark plug threads.
3. Install the spark plug with the
spark plug wrench, and then tight-
en it to the specified torque.
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. However, the spark
plug should be tightened to the speci-fied torque as soon as possible.
4. Install the spark plug cap.
1. Spark plug wrench
Specified spark plug:
NGK/CR6HSA
DENSO/U20FSR-U1. Spark plug gapSpark plug gap:
0.6–0.7 mm (0.024–0.028 in)
Tightening torque:
Spark plug:
12.5 Nm (1.25 m·kgf, 9.0 ft·lbf)
5KRE2.book Page 7 Monday, June 23, 2003 3:32 PM

PERIODIC MAINTENANCE AND MINOR REPAIR
6-36
6
EAU25891
Troubleshooting chart
WARNING
EWA10840
Keep away open flames and do not smoke while checking or working on the fuel system.
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.
There is no fuel.
Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the electric starter.2. Compression
There is compression.
There is no compression.
Check the ignition.
Have a Yamaha dealer
check the vehicle.
Remove the spark plugs
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gaps, or replace the spark plugs.
Have a Yamaha dealer check the vehicle.
The engine does not start.
Have a Yamaha dealer
check the vehicle.
The engine does not start.
Check the battery.
Operate the electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and charge the battery if necessary.
DryWet
Open the throttle halfway and operate
the electric starter.
5KRE2.book Page 36 Monday, June 23, 2003 3:32 PM