2006 YAMAHA YBR125 maintenance

PERIODIC MAINTENANCE AND MINOR REPAIR
6-6
6To install the cowling
1. Place the cowling in the original
position, and then install the
screws.
2. Install the carrier by installing the
bolts, and then tightening them to
the specified torque.3. Place the seat in the original posi-
tion, and then tighten the bolts.
4. Install the panels.
EAU37070
Panel A
To remove the panel1. Remove the screw.2. Pull the front of the panel out, and
then slide the panel forward to re-
lease it in the rear.
To install the panel
1. Secure the rear of the panel, and
then push the front of the panel in.
1. Screw
2. Cowling
Tightening torque:
Carrier bolt:
30 Nm (3.0 m·kgf, 22 ft·lbf)
1. Screw
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-7
6 2. Install the screw.
EAU36960
Panel B
To remove the panel1. Slide the panel lock cover open, in-
sert the key into the lock, and then
turn it 1/4 turn clockwise.2. Pull the front of the panel out with
the key inserted in the lock, and
then slide the panel forward to re-
lease it in the rear.To install the panel
1. Secure the rear of the panel, and
then push the front of the panel in
with the key inserted in the lock.
2. Turn the key counterclockwise to
the original position, remove it, and
then close the panel lock cover.
1. Panel lock cover
2. Unlock.
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-8
6
EAU19602
Checking the spark plug The spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic mainte-
nance and lubrication chart. In addition,
the condition of the spark plug can re-
veal the condition of the engine.
To remove the spark plug
1. Remove the spark plug cap.
2. Remove the spark plug as shown,
with the spark plug wrench includ-
ed in the owner’s tool kit.To check the spark plug
1. Check that the porcelain insulator
around the center electrode of the
spark plug is a medium-to-light tan
(the ideal color when the vehicle is
ridden normally).
NOTE:
If the 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.
2. Check the spark plug for electrode
erosion and excessive carbon or
other deposits, and replace it if
necessary.To install the 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.
1. Spark plug cap
1. Spark plug wrench
Specified spark plug:
NGK/CR6HSA1. Spark plug gapSpark plug gap:
0.6–0.7 mm (0.024–0.028 in)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-9
6 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.
EAU37170
Engine oil The engine oil level should be checked
before each ride. In addition, the oil
must be changed at the intervals spec-
ified in the periodic maintenance and
lubrication chart.
To check the engine oil level
1. Place the vehicle on the center-
stand.NOTE:Make sure that the vehicle is positioned
straight up when checking the oil level.
A slight tilt to the side can result in afalse reading.
2. Start the engine, warm it up for
several minutes, and then turn it
off.
3. Wait a few minutes until the oil set-
tles, remove the oil filler cap, wipe
the dipstick clean, insert it back
into the oil filler hole (without
screwing it in), and then remove it
again to check the oil level.
NOTE:
The engine oil should be between theminimum and maximum level marks.
Tightening torque:
Spark plug:
12.5 Nm (1.25 m·kgf, 9.0 ft·lbf)
1. Engine oil filler cap
1. Dipstick
2. Maximum level mark
3. Minimum level mark
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-10
64. If the engine oil is at or below the
minimum level mark, add sufficient
oil of the recommended type to
raise it to the correct level.
5. Insert the dipstick into the oil filler
hole, and then tighten the oil filler
cap.
To change the engine oil
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.
3. Remove the engine oil filler cap
and drain bolt to drain the oil from
the crankcase.4. Install the engine oil drain bolt, and
then tighten it to the specified
torque.
5. Add the specified amount of the
recommended engine oil, and then
install and tighten the engine oil fill-
er cap.
CAUTION:
ECA11620


In order to prevent clutch slip-
page (since the engine oil also
lubricates the clutch), do not
mix any chemical additives. Do
not use oils with a diesel speci-
fication of “CD” or oils of a high-
er quality than specified. In
addition, do not use oils labeled
“ENERGY CONSERVING II” or
higher.


Make sure that no foreign mate-rial enters the crankcase.
6. Start the engine, and then let it idle
for several minutes while checking
it for oil leakage. If oil is leaking, im-
mediately turn the engine off and
check for the cause.
7. Turn the engine off, and then
check the oil level and correct it if
necessary.
1. Engine oil drain bolt
2. Oil pan
Tightening torque:
Engine oil drain bolt:
20 Nm (2.0 m·kgf, 14 ft·lbf)
Recommended engine oil:
See page 8-1.
Oil change quantity:
1.00 L (1.06 US qt) (0.88 Imp.qt)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-11
6
EAU37120
Cleaning the air filter element The air filter element should be cleaned
at the intervals specified in the periodic
maintenance and lubrication chart.
Clean the air filter element more fre-
quently if you are riding in unusually
wet or dusty areas.
1. Remove panel A. (See page 6-5.)
2. Remove the air filter case cover by
removing the screws.
3. Remove the air filter element.4. Remove the sponge material from
the air filter element.
5. Lightly tap the air filter element to
remove most of the dust and dirt,
and then blow the remaining dirt
out with compressed air on the
mesh side as shown. If the air filter
element is damaged, replace it.6. Clean the sponge material with
solvent, then squeeze the remain-
ing solvent out, and be sure to let
the sponge material dry before in-
stalling it into the air filter element.
If the sponge material is damaged,
replace it.
WARNING
EWA10430
Use only a dedicated parts cleaning
solvent. To avoid the risk of fire or
explosion, do not use gasoline orsolvents with a low flash point.
1. Screw
2. Air filter case cover
1. Sponge material
2. Air filter element
1. Air filter element
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-12
6
CAUTION:
ECA15100
To avoid damaging the sponge ma-
terial, handle it gently and carefully,and do not twist it.
7. Install the sponge material into the
air filter element, and then install
the air filter element into the air fil-
ter case.CAUTION:
ECA10480


Make sure that the air filter ele-
ment is properly seated in the
air filter case.


The engine should never be op-
erated without the air filter ele-
ment installed, otherwise the
piston(s) and/or cylinder(s) maybecome excessively worn.
8. Install the air filter case cover by in-
stalling the screws.
9. Check the hose at the bottom of
the air filter case for accumulated
dust or water, and if necessary,
drain it by removing the clamp, and
then removing the plug.10. Install the plug into the check
hose, and then install the clamp.
11. Install the panel.
EAU21280
Adjusting the carburetor The carburetor is an important part of
the engine and requires very sophisti-
cated adjustment. Therefore, most car-
buretor adjustments should be left to a
Yamaha dealer, who has the neces-
sary professional knowledge and expe-
rience. The adjustment described in the
following section, however, may be ser-
viced by the owner as part of routine
maintenance.CAUTION:
ECA10550
The carburetor has been set and ex-
tensively tested at the Yamaha fac-
tory. Changing these settings
without sufficient technical knowl-
edge may result in poor perfor-mance of or damage to the engine.
1. Clamp
2. Air filter check hose plug
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-13
6
EAU21320
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 lubrication
chart.
The engine should be warm before
making this adjustment.NOTE:
The engine is warm when it quickly re-sponds to the throttle.
Check the engine idling speed and, if
necessary, adjust it to specification by
turning the throttle stop screw. To in-
crease the engine idling speed, turn the
screw in direction (a). To decrease the
engine idling speed, turn the screw in
direction (b).
NOTE:
If the specified idling speed cannot be
obtained as described above, have aYamaha dealer make the adjustment.
EAU21370
Adjusting the throttle cable
free play The throttle cable free play should mea-
sure 3.0–7.0 mm (0.12–0.28 in) at the
throttle grip. Periodically check the
throttle cable free play and, if neces-
sary, adjust it as follows.NOTE:The engine idling speed must be cor-
rectly adjusted before checking and ad-justing the throttle cable free play.
1. Loosen the locknut.
1. Throttle stop screw
Engine idling speed:
1300–1500 r/min
1. Throttle cable free play
2. Locknut
3. Adjusting nut
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