2014 YAMAHA YBR125 torque

PERIODIC MAINTENANCE AND ADJUSTMENT
6-2
6
EAU17342
Owner’s tool kitThe owner’s tool kit is located behind
panel B. (See page 6-7.)
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.TIPIf you do not have the tools or experi-
ence required for a particular job, have
a Yamaha dealer perform it for you.1. Owner’s tool kit
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-9
6To check the spark plu
g
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 vehi-
cle is ridden normally).
TIPIf 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 check
the vehicle.
2. Check the spark plug for electrodeerosion and excessive carbon or
other deposits, and replace it if
necessary.
3. Measure the spark plug gap with a wire thickness gauge and, if nec-
essary, adjust the gap to specifi-
cation. To install the spark plu
g
1. Clean the surface of the spark plug gasket and its mating surfa-
ce, and then wipe off any grime
from the spark plug threads.
2. Install the spark plug with the spark plug wrench, and then tight-
en it to the specified torque.
TIPIf 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
specified torque as soon as possible.3. Install the spark plug cap.
1. Spark plug wrench
Specifie d spark plu g:
NGK/CR6HSA1. Spark plug gapSpark plu g g ap:
0.6–0.7 mm (0.024–0.028 in)
Ti ghtenin g torque:
Spark plug: 13 Nm (1.3 m·kgf, 9.4 ft·lbf)
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-11
64. Install the engine oil drain bolt and
its new gasket, and then tighten
the bolt to the specified torque.
5. Refill with the specified amount of the recommended engine oil, and
then install and tighten the oil filler
cap.
NOTICE
ECA11621
In or der to prevent clutch slip-
pa ge (since the en gine oil also
lu bricates the clutch), do not
mix any chemical additives. Do
not use oils with a diesel speci-
fication of “CD” or oils of a hi gh-
er quality than specifie d. In
a ddition, do not use oils la beled
“ENERGY CONSERVING II” or
hi gher.
 Make sure that no forei gn 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,
immediately turn the engine off
and check for the cause.
7. Turn the engine off, wait a few mi- nutes until the oil settles, and then
check the oil level and correct it if
necessary.
EAU37124
Cleanin g the air filter elementThe air filter element should be cleaned
at the intervals specified in the periodic
maintenance and lubrication chart.
Clean or, if necessary, replace the air
filter element more frequently if you are
riding in unusually wet or dusty areas.
1. Remove panel A. (See page 6-7.)
2. Remove the air filter case cover by removing the screws.
3. Remove the air filter element.
1. Engine oil drain bolt
2. Gasket
3. Oil panTi ghtenin g 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)3
2
1
1. Screw
2. Air filter case cover
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-22
6
EAU51241
To adjust the drive chain slack
Consult a Yamaha dealer before ad-
justing the drive chain slack. 1. Take the motorcycle off the cen- terstand, and then put the side-
stand down.
2. Remove the brake torque rod cot- ter pin, and then loosen the brake
pedal free play adjusting nut,
brake torque rod nut, and axle nut.
3. Loosen the drive chain puller lock- nut at each end of the swingarm. 4. Place the motorcycle on the cen-
terstand.
5. To tighten the drive chain, turn the drive chain slack adjusting bolt at
each end of the swingarm in direc-
tion (a). To loosen the drive chain,
turn the adjusting bolt at each end
of the swingarm in direction (b),
and then push the rear wheel for-
ward. NOTICE: Improper d rive
chain slack will overloa d the en-
g ine as well as other vital parts
of the motorcycle an d can lead
to chain slippa ge or b reakage.
To prevent this from occurrin g,
keep the drive chain slack with-
in the specifie d limits.
[ECA10572]
TIPUsing the alignment marks on each
side of the swingarm, make sure that
both drive chain pullers are in the same
position for proper wheel alignment.
6. Take the motorcycle off the cen-
terstand, and then put the side-
stand down.
7. Tighten both locknuts, and then tighten the axle nut and brake
torque rod nut to their specified
torques.
8. Insert a new cotter pin.
1. Drive chain slack adjusting bolt
2. Drive chain puller locknut
3. Axle nut
4. Brake torque rod nut
5. Brake torque rod cotter pin
6. Brake pedal free play adjusting nut
1
2
34
5
6
1. Alignment marks
2. Drive chain puller
3. Drive chain puller locknut
4. Drive chain slack adjusting bolt
Ti ghtenin g torques:
Axle nut: 80 Nm (8.0 m·kgf, 58 ft·lbf)
Brake torque rod nut: 19 Nm (1.9 m·kgf, 14 ft·lbf)
1
2
3
4
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-34
6
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.
TIPMake 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 the
retainer on the fork leg.3. Insert the wheel axle, and then in-stall the washer and axle nut.
4. Take the motorcycle off the cen- terstand so that the front wheel is
on the ground, and then put the
sidestand down.
5. Tighten the axle nut to the speci- fied torque, and then install the
rubber cap so that it fits over the
washer. 6. While applying the front brake,
push down hard on the handle-
bars several times to check if the
front fork compresses and re-
bounds smoothly.
7. Connect the speedometer cable.
1. Wheel axle
1. Speedometer gear unit
1
1. Speedometer gear unit retainer
Ti ghtenin g torque:
Axle nut:
59 Nm (5.9 m·kgf, 43 ft·lbf)
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-35
6
EAU25081
Rear wheel
EAU56650
To remove the rear wheel
WARNING
EWA10822
To avoid injury, securely support the
vehicle so there is no dan ger of it
fallin g 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 brake torque rod cot-
ter 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 discon-
nect the brake rod from the brake
camshaft lever. 5. Loosen the drive chain puller lock-
nut and the drive chain slack ad-
justing bolt on both ends of the
swingarm.
1. Axle nut
2. Brake torque rod
3. Brake torque rod nut and bolt
4. Brake torque rod cotter pin
13
2
4
1. Brake pedal free play adjusting nut
2. Brake rod
3. Brake camshaft lever
1. Wheel axle
2. Drive chain puller locknut
3. Drive chain slack adjusting bolt
3
1
2
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-36
6
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.
TIPThe drive chain does not need to be
disassembled in order to remove and
install the wheel.8. Remove the wheel.
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 in-
stall the brake pedal free play ad-
justing 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 cen-
terstand so that the rear wheel is
on the ground, and then put the
sidestand down.
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 6-18.)
WARNING
EWA10661
After a djustin g the brake ped al free
play, check the operation of the
b rake li ght.
EAU25852
Trou bleshootin gAlthough Yamaha motorcycles receive
a thorough inspection before shipment
from the factory, trouble may occur
during operation. Any problem in the
fuel, compression, or ignition systems,
for example, can cause poor starting
and loss of power.
The following troubleshooting chart
represents a quick and easy procedure
for checking these vital systems your-
self. However, should your motorcycle
require any repair, take it to a Yamaha
dealer, whose skilled technicians have
the necessary tools, experience, and
know-how to service the motorcycle
properly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look
like Yamaha parts, but they are often
inferior, have a shorter service life and
can lead to expensive repair bills.
WARNING
EWA15142
When checkin g the fuel system, d o
not smoke, an d make sure there are
no open flames or sparks in the ar-
ea, inclu din g pilot li ghts from water
Ti ghtenin g torques:
Brake torque rod nut: 19 Nm (1.9 m·kgf, 14 ft·lbf)
Axle nut:
80 Nm (8.0 m·kgf, 58 ft·lbf)
U51DE1E0.book Page 36 Thursday, August 29, 2013 4:41 PM