wheel YAMAHA YZF-R125 2020 User Guide

Periodic maintenance and adjustment
6-25
6
EAU22762
Drive chain slack
The drive chain slack should be
checked before each ride and adjusted
if necessary.
EAU74253To check the drive chain slack
1. Place the motorcycle on the side-
stand.
TIP
When checking and adjusting the drive
chain slack, there should be no weight
on the motorcycle.
2. Shift the transmission into the
neutral position.
3. Measure the drive chain slack as
shown.
4. If the drive chain slack is incorrect,
adjust it as follows. NOTICE: Im-
proper drive chain slack will
overload the engine as well as
other vital parts of the motorcy-
cle and can lead to chain slip-
page or breakage. To prevent
this from occurring, keep the
drive chain slack within the
specified limits.
[ECA10572]EAU3431B
To adjust the drive chain slack
Consult a Yamaha dealer before ad-
justing the drive chain slack.
1. Loosen the axle nut and the lock-
nut on each side of the swingarm.
2. To tighten the drive chain, turn the
drive chain slack adjusting bolt on
each side of the swingarm in di-
rection (a). To loosen the drive
chain, turn the adjusting bolt on
each side of the swingarm in di-
rection (b), and then push the rear
wheel forward.
TIP
Using 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.
3. Tighten the axle nut, then the lock-
nuts to their specified torques.
1. Drive chain slack
Drive chain slack:
30.0–40.0 mm (1.18–1.57 in)
ZAUM1604
1
1. Drive chain slack adjusting bolt
2. Axle nut
3. Alignment marks
4. Locknut
Tightening torques:
Axle nut:
85 N·m (8.5 kgf·m, 63 lb·ft)
Locknut:
15 N·m (1.5 kgf·m, 11 lb·ft)
ZAUM1605
3 21
4
(b) (a)
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Periodic maintenance and adjustment
6-30
6
EAU23273
Checking the front fork
The condition and operation of the
front fork must be checked as follows
at the intervals specified in the periodic
maintenance and lubrication chart.
To check the condition
Check the inner tubes for scratches,
damage and excessive oil leakage.
To check the operation
1. Place the vehicle on a level sur-
face and hold it in an upright posi-
tion. WARNING! To avoid injury,
securely support the vehicle so
there is no danger of it falling
over.
[EWA10752]
2. 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.
NOTICE
ECA10591
If any damage is found or the front
fork does not operate smoothly,
have a Yamaha dealer check or re-
pair it.
EAU23285
Checking the steering
Worn or loose steering bearings may
cause danger. Therefore, the operation
of the steering must be checked as fol-
lows at the intervals specified in the
periodic maintenance and lubrication
chart.
1. Raise the front wheel off the
ground. (See page 6-36.)
WARNING! To avoid injury, se-
curely support the vehicle so
there is no danger of it falling
over.
[EWA10752]
2. Hold the lower ends of the front
fork legs and try to move them for-
ward and backward. If any free
play can be felt, have a Yamaha
dealer check or repair the steer-
ing.
ZAUM1187
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Periodic maintenance and adjustment
6-31
6
EAU23292
Checking the wheel bearings
The front and rear wheel bearings must
be checked at the intervals specified in
the periodic maintenance and lubrica-
tion chart. If there is play in the wheel
hub or if the wheel does not turn
smoothly, have a Yamaha dealer
check the wheel bearings.
EAU50583
Battery
The battery is located under the rider
seat. It is a VRLA (valve-regulated lead-
acid) battery. There is no need to check
the electrolyte or to add distilled water.
However, the battery lead connections
need to be checked, and tightened if
necessary.
WARNING
EWA10761
Electrolyte is poisonous and
dangerous since it contains sul-
furic acid, which causes severe
burns. Avoid any contact with
skin, eyes or clothing and al-
ways shield your eyes when
working near batteries. In case
of contact, administer the fol-
lowing FIRST AID.
EXTERNAL: Flush with plenty
of water.
INTERNAL: Drink large quan-
tities of water or milk and im-
mediately call a physician.
EYES: Flush with water for 15
minutes and seek prompt
medical attention.
1. Rubber cover
2. Negative battery lead (black)
3. Battery
4. Battery band
5. Positive battery lead (red)
ZAUM1613
123
4
5
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Periodic maintenance and adjustment
6-36
6
EAU67131
Supporting the motorcycle
Since this model is not equipped with a
centerstand, use maintenance stands
when removing the front or rear wheel
or when performing other maintenance
that requires the motorcycle to stand
up right.
Check that the motorcycle is in a stable
and level position before starting any
maintenance.
EAU25872
Troubleshooting
Although 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 charts
represent quick and easy procedures
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 checking the fuel system, do
not smoke, and make sure there are
no open flames or sparks in the ar-
ea, including pilot lights from water
heaters or furnaces. Gasoline or
gasoline vapors can ignite or ex-
plode, causing severe injury or prop-
erty damage.
1. Maintenance stand (example)
1
UB5GE1E0.book Page 36 Monday, August 26, 2019 3:02 PM

Motorcycle care and storage
7-1
7
EAU37834
Matte color caution
NOTICE
ECA15193
Some models are equipped with
matte colored finished parts. Be
sure to consult a Yamaha dealer for
advice on what products to use be-
fore cleaning the vehicle. Using a
brush, harsh chemical products or
cleaning compounds when cleaning
these parts will scratch or damage
their surface. Wax also should not
be applied to any matte colored fin-
ished parts.
EAU83443
Care
Frequent, thorough cleaning of the ve-
hicle will not only enhance its appear-
ance but also will improve its general
performance and extend the useful life
of many components. Washing, clean-
ing, and polishing will also give you a
chance to inspect the condition of the
vehicle more frequently. Be sure to
wash the vehicle after riding in the rain
or near the sea, because salt is corro-
sive to metals.
TIP
The roads of heavy snowfall areas
may be sprayed with salt as a de-
icing method. This salt can stay on
the roads well into spring, so be
sure to wash the underside and
chassis parts after riding in such
areas.
Genuine Yamaha care and main-
tenance products are sold under
the YAMALUBE brand in many
markets worldwide.
See your Yamaha dealer for addi-
tional cleaning tips.
NOTICE
ECA26280
Improper cleaning can cause cos-
metic and mechanical damage. Do
not use:
high-pressure washers or
steam-jet cleaners. Excessive
water pressure may cause wa-
ter seepage and deterioration of
wheel bearings, brakes, trans-
mission seals and electrical de-
vices. Avoid high-pressure
detergent applications such as
those available in coin-operated
car washers.
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Motorcycle care and storage
7-2
7harsh chemicals, including
strong acidic wheel cleaners,
especially on spoke or magne-
sium wheels.
harsh chemicals, abrasive
cleaning compounds, or wax on
matte-finished parts. Brushes
can scratch and damage the
matte-finish, use soft sponge or
towel only.
towels, sponges, or brushes
contaminated with abrasive
cleaning products or strong
chemicals such as, solvents,
gasoline, rust removers, brake
fluid, or antifreeze, etc.
Before washing
1. Park the vehicle out of direct sun-
light and allow it to cool. This will
help avoid water spots.
2. Make sure all caps, covers, elec-
trical couplers and connectors are
tightly installed.
3. Cover the muffler end with a plas-
tic bag and a strong rubber band.
4. Pre-soak stubborn stains like in-
sects or bird droppings with a wet
towel for a few minutes.
5. Remove road grime and oil stains
with a quality degreasing agent
and a plastic-bristle brush or
sponge. NOTICE: Do not use
degreasing agent on areas re-
quiring lubrication such as
seals, gaskets, and wheel axles.
Follow product instructions.
[ECA26290]
Washing
1. Rinse off any degreaser and spray
down the vehicle with a garden
hose. Use only enough pressure
to do the job. Avoid spraying wa-
ter directly into the muffler, instru-
ment panel, air inlet, or other inner
areas such as underseat storage
compartments.
2. Wash the vehicle with a quality au-
tomotive-type detergent mixed
with cool water and a soft, clean
towel or sponge. Use an old tooth-
brush or plastic-bristle brush for
hard-to-reach places. NOTICE:
Use cold water if the vehicle has
been exposed to salt. Warm wa-
ter will increase salt’s corrosive
properties.
[ECA26301]
3. For windshield-equipped vehicles:
Clean the windshield with a soft
towel or sponge dampened with
water and a pH neutral detergent.
If necessary, use a high-quality
windshield cleaner or polish for
motorcycles. NOTICE: Never use
any strong chemicals to clean
the windshield. Additionally,
some cleaning compounds for
plastic may scratch the wind-
shield, so be sure to test all
cleaning products before gen-
eral application.
[ECA26310]
4. Rinse off thoroughly with clean
water. Be sure to remove all deter-
gent residues, as they can be
harmful to plastic parts.
After washing
1. Dry the vehicle with a chamois or
absorbent towel, preferably mi-
crofiber terrycloth.
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Motorcycle care and storage
7-5
7 8. Check and correct the tire air
pressure, and then lift the vehicle
so that all wheels are off the
ground. Otherwise, turn the
wheels a little once a month in or-
der to prevent the tires from be-
coming degraded in one spot.
9. Cover the muffler outlet with a
plastic bag to prevent moisture
from entering it.
10. Remove the battery and fully
charge it, or attach a maintenance
charger to keep the battery opti-
mally charged. NOTICE: Confirm
that the battery and its charger
are compatible. Do not charge a
VRLA battery with a convention-
al charger.
[ECA26330]
TIP
If the battery will be removed,
charge it once a month and store
it in a temperate location between
0-30 °C (32-90 °F).
See page 6-31 for more informa-
tion on charging and storing the
battery.
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Specifications
8-1
8
Dimensions:
Overall length:
1990 mm (78.3 in)
Overall width:
755 mm (29.7 in)
Overall height:
1140 mm (44.9 in)
Seat height:
820 mm (32.3 in)
Wheelbase:
1325 mm (52.2 in)
Ground clearance:
160 mm (6.30 in)
Minimum turning radius:
2.9 m (9.51 ft)
Weight:
Curb weight:
142 kg (313 lb)
Engine:
Combustion cycle:
4-stroke
Cooling system:
Liquid cooled
Valve train:
SOHC
Number of cylinders:
Single cylinder
Displacement:
124 cm³
Bore × stroke:
52.0 × 58.6 mm (2.05 × 2.31 in)
Starting system:
Electric starter
Engine oil:
Recommended brand:
SAE viscosity grades:
10W-40
Recommended engine oil grade:
API service SG type or higher, JASO
standard MA
Engine oil quantity:
Oil change:
0.85 L (0.90 US qt, 0.75 Imp.qt)
With oil filter removal:
0.95 L (1.00 US qt, 0.84 Imp.qt)
Coolant quantity:
Coolant reservoir (up to the maximum level
mark):
0.15 L (0.16 US qt, 0.13 Imp.qt)
Radiator (including all routes):
0.49 L (0.52 US qt, 0.43 Imp.qt)
Fuel:
Recommended fuel:
Unleaded gasoline (E10 acceptable)
Octane number (RON):
95
Fuel tank capacity:
11 L (2.9 US gal, 2.4 Imp.gal)
Fuel reserve amount:
3.0 L (0.79 US gal, 0.66 Imp.gal)
Fuel injection:
Throttle body:
ID mark:
B5G1 00
Drivetrain:
Gear ratio:
1st:
2.833 (34/12)
2nd:
1.875 (30/16)
3rd:
1.364 (30/22)
4th:
1.143 (24/21)
5th:
0.957 (22/23)
6th:
0.840 (21/25)
Front tire:
Type:
Tubeless
Size:
100/80-17M/C 52S
Manufacturer/model:
MICHELIN PILOT STREET
Rear tire:
Type:
Tubeless
Size:
140/70-17M/C 66S
Manufacturer/model:
MICHELIN PILOT STREET
Loading:
Maximum load:
178 kg (392 lb)
UB5GE1E0.book Page 1 Monday, August 26, 2019 3:02 PM

Index
10-2
10
Turn signal switch ................................. 3-12
V
Valve clearance..................................... 6-16
Vehicle identification number ................. 9-1
Vehicle lights ......................................... 6-34
W
Wheel bearings, checking..................... 6-31
Wheels .................................................. 6-19
Y
Yamalube .............................................. 6-12
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