YAMAHA YBR125 2008 Service Manual

PERIODIC MAINTENANCE AND MINOR REPAIR
6-9
6
EAU37171
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.4. 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.1. Engine oil filler cap
1. Dipstick
2. Maximum level mark
3. Minimum level mark
1. Engine oil drain bolt
2. Oil pan
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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
6-11
6 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.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.
1. Air filter element
2. Sponge material
2
1
1. Air filter element
1
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-12
69. 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.
EAU44730
Checking the engine idling
speed The engine idling speed must be
checked as follows and, if necessary,
adjusted by a Yamaha dealer at the in-
tervals specified in the periodic mainte-
nance and lubrication chart.
Start the engine and warm it up for sev-
eral minutes at 1000–2000 r/min while
occasionally revving it to 4000–5000
r/min.
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. Clamp
2. Air filter check hose plug
Engine idling speed:
1300–1500 r/min
1. Throttle cable free play
2. Locknut
3. Throttle cable free play adjusting nut
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-13
6 2. 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.
EAU21561
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
EWA10500


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 MINOR REPAIR
6-14
6
WARNING
EWA11020
Because loading has an enormous
impact on the handling, braking,
performance and safety characteris-
tics of your motorcycle, you should
keep the following precautions in
mind.

NEVER OVERLOAD THE
MOTORCYCLE! Operation of an
overloaded motorcycle may re-
sult in tire damage, loss of con-
trol, or severe injury. Make sure
that the total weight of rider,passenger, cargo, and accesso-
ries does not exceed the speci-
fied maximum load for the
vehicle.


Do not carry along loosely
packed items, which can shift
during a ride.


Securely pack the heaviest
items close to the center of the
motorcycle and distribute the
weight evenly on both sides.


Adjust the suspension and tire
air pressure with regard to the
load.


Check the tire condition and airpressure before each ride.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.
NOTE:The tire tread depth limits may differ
from country to country. Always complywith the local regulations.
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)
90–190 kg (198–419 lb):
Front:
175 kPa (1.75 kgf/cm², 25 psi)
Rear:
280 kPa (2.80 kgf/cm², 41 psi)
Maximum load*:
190 kg (419 lb)
* Total weight of rider, passenger, car-
go and accessories
1. Tire sidewall
2. Tire tread depthMinimum tire tread depth (front and
rear):
1.6 mm (0.06 in)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-15
6 Tire information
This motorcycle is equipped with cast
wheels and tubeless tires.
WARNING
EWA10460


The front and rear tires should
be of the same make and de-
sign, otherwise the handling
characteristics of the vehicle
cannot be guaranteed.


After extensive tests, only the
tires listed below have been ap-
proved for this model byYamaha Motor Co., Ltd.
WARNING
EWA10470


Have a Yamaha dealer replace
excessively worn tires. Besides
being illegal, operating the vehi-
cle 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.
Front tire:
Size:
3.00-18 47P
Manufacturer/model:
CHENG SHIN/C-6039
Rear tire:
Size:
3.50-16 58P
Manufacturer/model:
CHENG SHIN/C-289
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-16
6
EAU22032
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. Loosen the locknut at the clutch le-
ver.
2. To increase the clutch lever free
play, turn the clutch lever free play
adjusting bolt in direction (a). To
decrease the clutch lever free play,
turn the adjusting bolt in direction
(b).3. If the specified clutch lever free
play could be obtained as de-
scribed above, tighten the locknut
and skip the rest of the procedure,
otherwise, proceed as follows.
4. Fully turn the adjusting bolt in di-
rection (a) to loosen the clutch ca-
ble.
5. Loosen the locknut further down
the clutch cable.
6. To increase the clutch lever free
play, turn the clutch lever free play
adjusting nut in direction (a). To
decrease the clutch lever free play,
turn the adjusting nut in direction
(b).7. Tighten both locknuts.1. Locknut (clutch lever)
2. Clutch lever free play adjusting bolt
3. Clutch lever free play
1. Locknut (clutch cable)
2. Clutch lever free play adjusting nut (clutch
cable)
1
2
(a) (b)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-17
6
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.
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.
1. Brake lever free play
1. Brake pedal free play
1. Brake pedal free play adjusting nut
1(a)
(b)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-18
6
EAU44820
Checking the shift pedal The operation of the shift pedal should
be checked before each ride. If opera-
tion is not smooth, have a Yamaha
dealer check the vehicle.
EAU22291
Adjusting the rear brake light
switch The rear brake light switch, which is ac-
tivated by the brake pedal, is properly
adjusted when the brake light comes
on just before braking takes effect. If
necessary, adjust the brake light switch
as follows.
1. Remove panel B. (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. Rear brake light switch
2. Rear brake light switch adjusting nut
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