2000 YAMAHA XVS125 engine

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PERIODIC MAINTENANCE AND MINOR REPAIR
6Do not attempt to diagnose such
problems yourself. Instead, take the
motorcycle to a Yamaha dealer. You
should periodically remove and
inspect the spark plugs because heat
and deposits will cause any spark
plug to slowly break down and erode.
If electrode erosion becomes exces-
sive, or if carbon and other deposits
are excessive, you should replace
the spark plug with the specified plug.
1
2. Use the spark plug wrench in the
tool kit to remove the spark plugs
as shown.
1. Spark plug wrench
Specified spark plug:
CR7HSA (NGK) or
U22FSR-U (DENSO)
Inspection
The spark plug is an important
engine component and is easy to
inspect. The condition of the spark
plug can indicate the condition of the
engine.
Normally, all spark plugs from the
same engine should have the same
color on the white insulator around
the center electrode. The ideal color
at this point is a medium-to-light tan
color for a motorcycle that is being
ridden normally. If one spark plug
shows a distinctly different color,
there could be something wrong with
the engine.
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PERIODIC MAINTENANCE AND MINOR REPAIR
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To install the spark plugs
1. Measure the electrode gap with
a wire thickness gauge and, if
necessary, adjust the gap to
specification.
2. Clean the gasket surface. Wipe
off any grime from the threads.
3. Install the spark plug and tighten
it to the specified torque.
NOTE:
If a torque wrench is not available
when you are installing a spark plug,
a good estimate of the correct torque
is 1/4 to 1/2 turn past finger tight.
Have the spark plug tightened to the
specified torque as soon as possible.
4. Install the spark plug caps.
Spark plug gap:
0.6 – 0.7 mm
Tightening torque:
Spark plug:
12.5 Nm (1.25 m0kg)
a
a. Spark plug gap
EAU01523
Engine oil and oil filter
element
The engine oil level should be
checked before each ride. In addition,
the oil must be changed and the oil
filter element replaced at the intervals
specified in the periodic maintenance
and lubrication chart.
To check the engine oil level
1. Place the motorcycle on a level
surface and hold it in an upright
position.
NOTE:
Make sure that the motorcycle is
positioned straight up when checking
the oil level. A slight tilt to the side
can result in a false reading.
2. Start the engine, warm it up for
several minutes, and then turn it
off.
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PERIODIC MAINTENANCE AND MINOR REPAIR
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93. Wait a few minutes until the oil
settles, and then check the oil
level through the check window
located at the bottom-right side
of the crankcase.
NOTE:
The engine oil should be between the
minimum and maximum level marks.
4. If the engine oil is below the min-
imum level mark, add sufficient
oil of the recommended type to
raise it to the correct level.
1
To change the engine oil (with or
without oil filter element replace-
ment)
1. Start the engine, warm it up for
several minutes, and then turn it
off.
2. Place an oil pan under the
engine to collect the used oil.
1. Engine oil filler cap
3. Remove the engine oil filler cap
and drain bolt to drain the oil
from the crankcase.
NOTE:
Skip steps 4–6 if the oil filter element
is not being replaced.
1. Engine oil drain bolt
1
2
1
3
1. Oil level window
2. Maximum level mark
3. Minimum level mark
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6-11
5. Remove and replace the oil filter
element and O-ring.
6. Install the oil filter element cover
by installing the bolts, then tight-
ening them to the specified
torque.
NOTE:
Make sure that the O-ring is properly
seated.
1
7. Install the engine oil drain bolt,
and then tighten it to the speci-
fied torque.
8. Add the specified amount of the
recommended engine oil, and
then install and tighten the oil
filler cap.
Tightening torque:
Oil filter element cover bolt:
10 Nm (1.0 m·kg)
4. Remove the oil filter element
cover by removing the bolts.
1. Bolt (´3) 1. Oil filter element
2. O-ring
2
1
Tightening torque:
Engine oil drain bolt:
23 Nm (2.3 m·kg)
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PERIODIC MAINTENANCE AND MINOR REPAIR
EC000072
cC
8In order to prevent clutch slip-
page (since the engine oil also
lubricates the clutch), do not
mix any chemical additives
with the oil or use oils of a
higher grade than “CD”. In
addition, do not use oils
labeled “ENERGY CONSERV-
ING II” or higher.
8Make sure that no foreign
material enters the crankcase.
9. Start the engine, and then let it
idle for several minutes while
checking it for oil leakage. If oil is
leaking, immediately turn the
engine off and check for the
cause.
10. Turn the engine off, and then
check the oil level and correct it if
necessary. Recommended oil:
See page 8-1.
Oil quantity:
With oil filter element
replacement:
1.6 L
Without oil filter element
replacement:
1.4 L
Total amount (dry engine):
1.75 L
EAU03186*
Cleaning the air filter
element
The air filter element should be
cleaned at the intervals specified in
the periodic maintenance and lubrica-
tion chart. Clean the air filter element
more frequently if you are riding in
unusually wet or dusty areas.
1. Remove the air filter case by
removing the bolts and loosening
the clamp screw.
1. Bolt (´2)
2. Clamp screw
1
2
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EAU01168
Adjusting the engine idling
speed
The engine idling speed must be
checked and, if necessary, adjusted
as follows at the intervals specified in
the periodic maintenance and lubrica-
tion chart.
NOTE:
A diagnostic tachometer is needed to
make this adjustment.
1. Attach the tachometer to the
spark plug lead.
2. Start the engine and warm it up
for several minutes at 1,000–
2,000 r/min while occasionally
revving it to 4,000–5,000 r/min.
NOTE:
The engine is warm when it quickly
responds to the throttle.
EC000082
cC
8Make sure that the air filter ele-
ment is properly seated in the
air filter case.
8The engine should never be
operated without the air filter
element installed, otherwise
the piston(s) and/or cylinder(s)
may become excessively
worn.
6. Install the air filter case cover by
installing the screws.
7. Install the air filter case by
installing the bolts and tightening
the clamp screw.
EAU00629
Adjusting the carburetor
The carburetor is an important part of
the engine and requires very sophisti-
cated adjustment. Therefore, most
carburetor adjustments should be left
to a Yamaha dealer, who has the
necessary professional knowledge
and experience. The adjustment
described in the following section,
however, may be serviced by the
owner as part of routine mainte-
nance.
EC000094
cC
The carburetor has been set and
extensively tested at the Yamaha
factory. Changing these settings
without sufficient technical knowl-
edge may result in poor perfor-
mance of or damage to the engine.
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3. Check the engine idling speed
and, if necessary, adjust it to
specification by turning the throt-
tle stop screw. To increase the
engine idling speed, turn the
screw in direction a. To
decrease the engine idling
speed, turn the screw in direction
b.
1. Throttle stop screw
NOTE:
If the specified idling speed cannot
be obtained as described above,
have a Yamaha dealer make the
adjustment.
1
b
a
EAU00635
Adjusting the throttle cable
free play
The throttle cable free play should
measure 3–5 mm at the throttle grip.
Periodically check the throttle cable
free play and, if necessary, have a
Yamaha dealer adjust it.
Engine idling speed:
1,250–1,450 r/min
a. Throttle cable free play
a
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PERIODIC MAINTENANCE AND MINOR REPAIR
EAU00637
Adjusting the valve
clearance
The valve clearance changes with
use, resulting in improper air-fuel mix-
ture and/or engine noise. To prevent
this from occurring, the valve clear-
ance must be adjusted by a Yamaha
dealer at the intervals specified in the
periodic maintenance and lubrication
chart.
EAU00647
Tires
To ensure maximum performance as
well as the long and safe operation of
your motorcycle, note the following
points regarding the specified tires.
Tire air pressure
The tire air pressure should be
checked and, if necessary, adjusted
before each ride.
EW000082
w
8The tire air pressure must be
checked and adjusted on cold
tires (i.e., when the tempera-
ture of the tires equals the
ambient temperature).
8The tire air pressure must be
adjusted in accordance with
the riding speed and with the
total weight of rider, passen-
ger, cargo, and accessories
approved for this model.
*Total weight of rider, passenger, cargo and
accessories
Tire air pressure (measured on cold tires)
Load* Front Rear
175 kPa 200 kPa
Up to 90 kg (1.75 kg/cm
2, (2.0 kg/cm2,1.75 bar) 2.00 bar)
90 kg load–225 kPa 225 kPa
maximum load*(2.25 kg/cm
2, (2.25 kg/cm2,
2.25 bar) 2.25 bar)
Maximum load* 183 kg
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