YAMAHA YBR125 2009 Service Manual

PERIODIC MAINTENANCE AND ADJUSTMENT
6-10
6 4. 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.
NOTICE
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.
EAU37122
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 6-6.)
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. Screw
2. Air filter case cover
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-11
64. 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! Use only a
dedicated parts cleaning sol-
vent. To avoid the risk of fire or
explosion, do not use gasoline
or solvents with a low flash
point.
[EWA10431]
NOTICE: To avoid
damaging the sponge material,
handle it gently and carefully,
and do not twist it.
[ECA15101]
7. Install the sponge material into the
air filter element, and then install
the air filter element into the air fil-
ter case. NOTICE: Make sure that
the air filter element is properly
seated in the air filter case. The
engine should never be operat-
ed without the air filter element
installed, otherwise the pis-
ton(s) and/or cylinder(s) may
become excessively worn.
[ECA10481]
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.
1. Sponge material
2. Air filter element
1. Air filter element
1
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-12
6 10. Install the plug into the check
hose, and then install the clamp.
11. Install the panel.
EAU44734
Checking the engine idling
speed Check the engine idling speed and, if
necessary, have it corrected by a
Yamaha dealer.
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.TIPThe engine idling speed must be cor-
rectly adjusted before checking and ad-justing the throttle cable free play.
1. Loosen the locknut.
1. Clamp
2. Air filter check hose plug
Engine idling speed:
1300–1500 r/min
1. Throttle cable free play
2. Locknut
3. Adjusting nut
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-13
62. To increase the throttle cable free
play, turn the adjusting nut in direc-
tion (a). To decrease the throttle
cable free play, turn the adjusting
nut in direction (b).
3. Tighten the locknut.
EAU21401
Valve clearance The valve clearance changes with use,
resulting in improper air-fuel mixture
and/or engine noise. To prevent this
from occurring, the valve clearance
must be adjusted by a Yamaha dealer
at the intervals specified in the periodic
maintenance and lubrication chart.
EAU21562
Tires To maximize the performance, durabil-
ity, and safe operation of your motor-
cycle, 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.
WARNING
EWA10501
Operation of this vehicle with im-
proper tire pressure may cause se-
vere injury or death from loss of
control.

The tire air pressure must be
checked and adjusted on cold
tires (i.e., when the temperature
of the tires equals the ambient
temperature).


The tire air pressure must be ad-
justed in accordance with the
riding speed and with the total
weight of rider, passenger, car-
go, and accessories approvedfor this model.
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-14
6
WARNING
EWA10511
Never overload your vehicle. Opera-
tion of an overloaded vehicle couldcause an accident.Tire inspection
The tires must be checked before each
ride. If the center tread depth reaches
the specified limit, if the tire has a nail or
glass fragments in it, or if the sidewall is
cracked, have a Yamaha dealer re-
place the tire immediately.
TIPThe tire tread depth limits may differ
from country to country. Always complywith the local regulations.Tire information
This motorcycle is equipped with cast
wheels and tubeless tires.
WARNING
EWA10461
The front and rear tires should be of
the same make and design, other-
wise the handling characteristics of
the vehicle may be different, whichcould lead to an accident.
After extensive tests, only the tires list-
ed below have been approved for this
model by Yamaha Motor Co., Ltd.
WARNING
EWA10470


Have a Yamaha dealer replace
excessively worn tires. Besides
being illegal, operating the vehi-
Tire air pressure (measured on cold
tires):
0–90 kg (0–198 lb):
Front:
175 kPa (1.75 kgf/cm², 25 psi)
Rear:
200 kPa (2.00 kgf/cm², 29 psi)
90–196 kg (198–432 lb):
Front:
175 kPa (1.75 kgf/cm², 25 psi)
Rear:
280 kPa (2.80 kgf/cm², 41 psi)
Maximum load*:
196 kg (432 lb)
* Total weight of rider, passenger, car-
go and accessories
1. Tire sidewall
2. Tire tread depth
Minimum tire tread depth (front and
rear):
1.6 mm (0.06 in)
Front tire:
Size:
2.75-18 42P
Manufacturer/model:
CHENG SHIN/C-910
Rear tire:
Size:
90/90-18 57P
Manufacturer/model:
CHENG SHIN/C-905
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-15
6cle with excessively worn tires
decreases riding stability and
can lead to loss of control.


The replacement of all wheel
and brake related parts, includ-
ing the tires, should be left to a
Yamaha dealer, who has the
necessary professional knowl-edge and experience.
EAU21960
Cast wheels To maximize the performance, durabil-
ity, and safe operation of your vehicle,
note the following points regarding the
specified wheels.

The wheel rims should be checked
for cracks, bends or warpage be-
fore each ride. If any damage is
found, have a Yamaha dealer re-
place the wheel. Do not attempt
even the smallest repair to the
wheel. A deformed or cracked
wheel must be replaced.


The wheel should be balanced
whenever either the tire or wheel
has been changed or replaced. An
unbalanced wheel can result in
poor performance, adverse han-
dling characteristics, and a short-
ened tire life.


Ride at moderate speeds after
changing a tire since the tire sur-
face must first be “broken in” for it
to develop its optimal characteris-
tics.
EAU22043
Adjusting the clutch lever free
play The clutch lever free play should mea-
sure 10.0–15.0 mm (0.39–0.59 in) as
shown. Periodically check the clutch le-
ver free play and, if necessary, adjust it
as follows.
1. Slide the rubber cover back at the
clutch lever.
2. Loosen the locknut.
3. To increase the clutch lever free
play, turn the adjusting bolt in di-
rection (a). To decrease the clutch
lever free play, turn the adjusting
bolt in direction (b).1. Locknut
2. Clutch lever free play adjusting bolt
3. Clutch lever free play
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-16
6
TIPIf the specified clutch lever free play
could be obtained as described above,skip steps 4–7.
4. Fully turn the adjusting bolt at the
clutch lever in direction (a) to loos-
en the clutch cable.
5. Loosen the locknut at the crank-
case.
6. To increase the clutch lever free
play, turn the adjusting nut in direc-
tion (a). To decrease the clutch le-
ver free play, turn the adjusting nut
in direction (b).7. Tighten the locknut at the crank-
case.
8. Tighten the locknut at the clutch le-
ver and then slide the rubber cover
to its original position.
EAUT1221
Checking the front brake lever
free play The brake lever free play should mea-
sure 0.0–7.0 mm (0.00–0.28 in) as
shown. Periodically check the brake le-
ver free play and, if necessary, have a
Yamaha dealer check the brake sys-
tem.
WARNING
EWA10641
An incorrect brake lever free play in-
dicates a hazardous condition in the
brake system. Do not operate the ve-
hicle until the brake system has
been checked or repaired by aYamaha dealer.
1. Locknut (crankcase)
2. Clutch lever free play adjusting nut (crank-
case)
1. Brake lever free play
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-17
6
EAU39812
Adjusting the brake pedal free
play The brake pedal free play should mea-
sure 20.0–30.0 mm (0.79–1.18 in) at
the brake pedal end as shown. Period-
ically check the brake pedal free play
and, if necessary, adjust it as follows.
To increase the brake pedal free play,
turn the adjusting nut at the brake rod in
direction (a). To decrease the brake
pedal free play, turn the adjusting nut in
direction (b).
WARNING
EWA10680


After adjusting the drive chain
slack or removing and installing
the rear wheel, always check the
brake pedal free play.


If proper adjustment cannot be
obtained as described, have a
Yamaha dealer make this ad-
justment.


After adjusting the brake pedal
free play, check the operation ofthe brake light.
EAU22292
Adjusting the rear brake light
switch The rear brake light, which is activated
by the brake pedal, should come on just
before braking takes effect. If neces-
sary, adjust the brake light switch as
follows.
1. Remove panel A. (See page 6-6.)
2. Turn the adjusting nut while hold-
ing the rear brake light switch in
place. To make the brake light
come on earlier, turn the adjusting
nut in direction (a). To make the
brake light come on later, turn the
adjusting nut in direction (b).
3. Install the panel.
1. Brake pedal free play
1. Brake pedal free play adjusting nut
1. Rear brake light switch
2. Rear brake light switch adjusting nut
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-18
6
EAU22380
Checking the front brake pads
and rear brake shoes The front brake pads and the rear brake
shoes must be checked for wear at the
intervals specified in the periodic main-
tenance and lubrication chart.
EAU22430
Front brake pads
Each front brake pad is provided with
wear indicator grooves, which allow
you to check the brake pad wear with-
out having to disassemble the brake.
To check the brake pad wear, check
the wear indicator grooves. If a brake
pad has worn to the point that the wearindicator grooves have almost disap-
peared, have a Yamaha dealer replace
the brake pads as a set.
EAU43170
Rear brake shoes
The rear brake is provided with a wear
indicator, which allows you to check the
brake shoe wear without having to dis-
assemble the brake. To check the
brake shoe wear, check the position of
the wear indicator while applying the
brake. If a brake shoe has worn to the
point that the wear indicator reaches
the wear limit mark, have a Yamaha
dealer replace the brake shoes as a
set.
EAU37001
Checking the front brake fluid
level Insufficient brake fluid may allow air to
enter the brake system, possibly caus-
ing it to become ineffective.
Before riding, check that the brake fluid
is above the minimum level mark and
replenish if necessary. A low brake fluid
level may indicate worn brake pads
and/or brake system leakage. If the
brake fluid level is low, be sure to check
the brake pads for wear and the brake
system for leakage.
Observe these precautions:
1. Brake pad wear indicator
1. Brake shoe wear limit mark
2. Brake shoe wear indicator
1
2
1. Minimum level mark
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-19
6


When checking the fluid level,
make sure that the top of the mas-
ter cylinder is level by turning the
handlebars.


Use only the recommended quality
brake fluid, otherwise the rubber
seals may deteriorate, causing
leakage and poor braking perfor-
mance.
TIPIf DOT 4 is not available, DOT 3 can beused.

Refill with the same type of brake
fluid. Mixing fluids may result in a
harmful chemical reaction and
lead to poor braking performance.


Be careful that water does not en-
ter the master cylinder when refill-
ing. Water will significantly lower
the boiling point of the fluid and
may result in vapor lock.


Brake fluid may deteriorate paint-
ed surfaces or plastic parts. Al-
ways clean up spilled fluid
immediately.


As the brake pads wear, it is nor-
mal for the brake fluid level to grad-
ually go down. However, if the
brake fluid level goes down sud-
denly, have a Yamaha dealer
check the cause.
EAU22721
Changing the brake fluid Have a Yamaha dealer change the
brake fluid at the intervals specified in
the TIP after the periodic maintenance
and lubrication chart. In addition, have
the oil seals of the brake master cylin-
der and caliper as well as the brake
hose replaced at the intervals listed be-
low or whenever they are damaged or
leaking.

Oil seals: Replace every two
years.


Brake hose: Replace every four
years.
Recommended brake fluid:
DOT 4
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