2008 YAMAHA YBR125 torque

PERIODIC MAINTENANCE AND MINOR REPAIR
6-1
6
EAU17240
Safety is an obligation of the owner. Pe-
riodic inspection, adjustment and lubri-
cation will keep your vehicle in the
safest and most efficient condition pos-
sible. The most important points of in-
spection, adjustment, and lubrication
are explained on the following pages.
The intervals given in the periodic
maintenance and lubrication chart
should be simply considered as a gen-
eral guide under normal riding condi-
tions. However, DEPENDING ON THE
WEATHER, TERRAIN, GEOGRAPHI-
CAL LOCATION, AND INDIVIDUAL
USE, THE MAINTENANCE INTER-
VALS MAY NEED TO BE SHORT-
ENED.
WARNING
EWA10320
If you are not familiar with mainte-
nance work, have a Yamaha dealerdo it for you.
EAU17340
Owner’s tool kit The owner’s tool kit is located behind
panel A. (See page 6-6.)
The service information included in this
manual and the tools provided in the
owner’s tool kit are intended to assist
you in the performance of preventive
maintenance and minor repairs. How-
ever, additional tools such as a torque
wrench may be necessary to perform
certain maintenance work correctly.NOTE:If you do not have the tools or experi-
ence required for a particular job, havea Yamaha dealer perform it for you.
WARNING
EWA10350
Modifications not approved by
Yamaha may cause loss of perfor-
mance and render the vehicle un-
safe for use. Consult a Yamaha
dealer before attempting any chang-es.
1. Owner’s tool kit
1
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-8
6To 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 oper-
ating improperly. Do not attempt to
diagnose such problems yourself. In-
stead, have a Yamaha dealer checkthe 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.
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/CR6HSA1. 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)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-10
64. Install the engine oil drain bolt, and
then tighten it to the specified
torque.
5. Refill with the specified amount of
the recommended engine oil, and
then install and tighten the engine
oil filler 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.
EAU37121
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 B. (See page 6-6.)
2. Remove the air filter case cover by
removing the screws.
3. Remove the air filter element.
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)
1.“CD” specification
2.“ENERGY CONSERVING II”
1
2
1. Screw
2. Air filter case cover
2
11
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-21
6
EAU22760
Drive chain slack The drive chain slack should be
checked before each ride and adjusted
if necessary.
EAU22793
To check the drive chain slack
1. Place the motorcycle on the cen-
terstand.
2. Shift the transmission into the neu-
tral position.
3. Spin the rear wheel several times
to locate the tightest portion of the
drive chain.
4. Measure the drive chain slack as
shown.5. If the drive chain slack is incorrect,
adjust it as follows.
EAU37112
To adjust the drive chain slack
1. Loosen the brake pedal free play
adjusting nut, brake torque rod nut,
and axle nut.
2. Loosen the chain puller locknut at
each end of the swingarm.3. To tighten the drive chain, turn the
adjusting bolt at each end of the
swingarm in direction (a). To loos-
en the drive chain, turn the adjust-
ing bolt at each end of the
swingarm in direction (b), and then
push the rear wheel forward.
NOTE:Using the alignment marks on each
side of the swingarm, make sure that
both chain pullers are in the same posi-tion for proper wheel alignment.
1. Drive chain slack
Drive chain slack:
20.0–30.0 mm (0.79–1.18 in)
1. Drive chain slack adjusting bolt
2. Chain puller locknut
3. Axle nut
4. Brake torque rod nut
5. Brake pedal free play adjusting nut
4
5 12
3
1. Alignment marks
2. Chain puller locknut
3. Drive chain slack adjusting bolt
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-22
6
CAUTION:
ECA10570
Improper drive chain slack will over-
load the engine as well as other vital
parts of the motorcycle and can lead
to chain slippage or breakage. To
prevent this from occurring, keep
the drive chain slack within thespecified limits.
4. Tighten both locknuts, and then
tighten the axle nut and brake
torque rod nut to their specified
torques.
5. Adjust the brake pedal free play.
(See page 6-17.)
WARNING
EWA10660
After adjusting the brake pedal free
play, check the operation of thebrake light.
EAU23022
Cleaning and lubricating the
drive chain The drive chain must be cleaned and
lubricated at the intervals specified in
the periodic maintenance and lubrica-
tion chart, otherwise it will quickly wear
out, especially when riding in dusty or
wet areas. Service the drive chain as
follows.CAUTION:
ECA10581
The drive chain must be lubricated
after washing the motorcycle andriding in the rain.
1. Clean the drive chain with kero-
sene and a small soft brush.CAUTION:
ECA11120
To prevent damaging the O-rings, do
not clean the drive chain with steam
cleaners, high-pressure washers orinappropriate solvents.
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive
chain with a special O-ring chain
lubricant.
CAUTION:
ECA11110
Do not use engine oil or any other lu-
bricants for the drive chain, as they
may contain substances that coulddamage the O-rings.
Tightening torques:
Axle nut:
80 Nm (8.0 m·kgf, 58 ft·lbf)
Brake torque rod nut:
19 Nm (1.9 m·kgf, 13 ft·lbf)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-33
6 5. Pull the wheel axle out, and then
remove the wheel.
CAUTION:
ECA11070
Do not apply the brake after the
wheel has been removed together
with the brake disc, otherwise thebrake pads will be forced shut.
EAU37030
To install the front wheel
1. Install the speedometer gear unit
into the wheel hub so that the pro-
jections mesh with the slots.2. Lift the wheel up between the fork
legs.
NOTE:
Make sure that there is enough space
between the brake pads before insert-
ing the brake disc and that the slot in
the speedometer gear unit fits over theretainer on the fork leg.3. Insert the wheel axle, making sure
the washer on the left side is in-
stalled with the beveled side facing
outward, and then install the axle
nut.
4. Take the motorcycle off the center-
stand so that the front wheel is on
the ground.
5. Tighten the axle nut to the speci-
fied torque, and then install both
rubber caps so that they fit over the
washers.
1. Rubber cap
2. Wheel axle
3. Washer
1. Speedometer gear unit
1. Speedometer gear unit retainer
Tightening torque:
Axle nut:
59 Nm (5.9 m·kgf, 43 ft·lbf)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-34
66. While applying the front brake,
push down hard on the handlebars
several times to check if the front
fork compresses and rebounds
smoothly.
7. Connect the speedometer cable.
EAU25080
Rear wheel
EAU37180
To remove the rear wheel
WARNING
EWA10820


It is advisable to have a Yamaha
dealer service the wheel.


Securely support the motor-
cycle so that there is no dangerof it falling over.
1. Loosen the axle nut and the brake
torque rod nut at the brake shoe
plate.
2. Disconnect the brake torque rod
from the brake shoe plate by re-
moving the cotter pin, the nut, and
the bolt.3. Place the motorcycle on the cen-
terstand.
4. Remove the brake pedal free play
adjusting nut, and then disconnect
the brake rod from the brake cam-
shaft lever.
1. Axle nut
2. Brake torque rod
3. Brake torque rod cotter pin
4. Brake torque rod nut and bolt
32 1
4
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-35
6 5. Loosen the chain puller locknut
and the drive chain slack adjusting
bolt on both ends of the swingarm.6. Remove the axle nut, and then pull
the wheel axle out.
7. Push the wheel forward, and then
remove the drive chain from the
rear sprocket.
NOTE:The drive chain does not need to be
disassembled in order to remove andinstall the wheel.
8. Remove the wheel.
EAU37192
To install the rear wheel
1. Install the wheel by inserting the
wheel axle from the left-hand side.
2. Install the drive chain onto the rear
sprocket.
3. Install the axle nut.
4. Install the brake rod onto the brake
camshaft lever, and then install the
brake pedal free play adjusting nut
onto the brake rod.
5. Connect the brake torque rod to
the brake shoe plate by installing
the bolt and nut.
6. Adjust the drive chain slack. (See
page 6-21.)7. Take the motorcycle off the center-
stand so that the rear wheel is on
the ground.
8. Tighten the brake torque rod nut
and axle nut to the specified
torques.
9. Insert a new cotter pin.
10. Adjust the brake pedal free play.
(See page 6-17.)
WARNING
EWA10660
After adjusting the brake pedal free
play, check the operation of thebrake light.
1. Brake pedal free play adjusting nut
2. Brake rod
3. Brake camshaft lever
1. Wheel axle
2. Chain puller locknut
3. Drive chain slack adjusting bolt1
23
Tightening torques:
Brake torque rod nut:
19 Nm (1.9 m·kgf, 13 ft·lbf)
Axle nut:
80 Nm (8.0 m·kgf, 58 ft·lbf)
U27SE0E0.book Page 35 Friday, February 22, 2008 8:54 AM