torque YAMAHA YS125 2017 Owners Manual

Periodic maintenance an d a djustment
6-2
6
EAU17342
Owner’s tool kitThe owner’s tool kit is located behind
panel B. (See page 6-8.)
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
1
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Periodic maintenance an d a djustment
6-11
6
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.
4. Install the Y.R.C.S. (Yamaha Ram-Air Cooling System) cap by install-
ing the bolts.
5. Install the cowling.
EAU78803
En gine oil an d oil filter ele-
mentThe engine oil level should be checked
before each ride. In addition, the oil
must be changed and the oil filter ele-
ment replaced at the intervals specified
in the periodic maintenance and lubri-
cation chart.
To check the en gine oil level
1. Place the vehicle on the center- stand. A slight tilt to the side can
result in a false 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 engine oil filler
cap, wipe the dipstick clean, insert
it back into the oil filler hole (with-
out screwing it in), and then re-
move it again to check the oil level.
WARNING! Never remove the
engine oil filler cap after hi gh-
speed operation, otherwise hot
en gine oil coul d spout out an d
cause damag e or injury. Always
let the en gine oil cool down suf-
1. Spark plug gapSpark plu g g ap:
0.8–0.9 mm (0.031–0.035 in)
Ti ghtenin g torque:
Spark plug: 13 N·m (1.3 kgf·m, 9.4 lb·ft)
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Periodic maintenance an d a djustment
6-13
6 5. Remove and replace the oil filter
element and O-ring.
6. Install the oil filter element cover by installing the bolts, then tight-
ening them to the specified
torque.
TIPMake sure that the O-ring is properly
seated.7. Install the engine oil drain bolt andits new gasket, and then tighten
the bolt to the specified torque. 8. Refill with the specified amount of
the recommended engine oil.
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.
9. Check the O-ring for damage, and replace it if necessary.
10. Install and tighten the engine oil filler cap.NOTICE
ECA10441
After chan gin g the en gine oil, b e
sure to check the oil pressure as de-
scri bed b elow.To check the oil pressure
1. Remove cowling A. (See page 6-8.)
2. Remove the Y.R.C.S. (Yamaha Ram-Air Cooling System) cap.
(See page 6-10.)
1. Oil filter element
2. O-ringTightenin g torque:
Oil filter element cover bolt: 10 N·m (1.0 kgf·m, 7.2 lb·ft)
2 1
Ti
ghtenin g torque:
Engine oil drain bolt:
20 N·m (2.0 kgf·m, 14 lb·ft)
Recommen ded en gine oil:
See page 8-1.
Oil quantity:
Oil change:1.00 L (1.06 US qt, 0.88 Imp.qt)
With oil filter removal:
1.10 L (1.16 US qt, 0.97 Imp.qt)
1. Engine oil filler cap
2. O-ring
21
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Periodic maintenance an d a djustment
6-14
6
3. Loosen the bleed bolt, start the
engine and keep it idling until oil
flows out. If no oil comes out after
several minutes, turn the engine
off immediately and consult a
Yamaha dealer for inspection.
4. After checking the oil pressure, tighten the bleed bolt with the
specified torque.
5. Install the Y.R.C.S. (Yamaha Ram- Air Cooling System) cap.
6. Install the cowling. 7. 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.
8. Turn the engine off, check the oil level and correct it if necessary.
EAUW3321
Cleanin g the air filter element
an d cleanin g the check hoseThe 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. In addition, the air
filter check hose must be frequently
checked and cleaned if necessary.
To clean the air filter element
1. Remove panel A. (See page 6-8.)
2. Remove the air filter case cover by removing the screws, and then
pull the air filter element out.
1. Bleed boltTightenin g torque:
Bleed bolt: 7 N·m (0.7 kgf·m, 5.1 lb·ft)
1
1. Air filter case cover
2. Screw
2 2
1
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Periodic maintenance an d a djustment
6-24
6
EAU22762
Drive chain slackThe drive chain slack should be
checked before each ride and adjusted
if necessary.
EAU22799
To check the drive chain slack
1. Place the motorcycle on the cen- terstand.
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
overloa d the en gine as well as
other vital parts of the motorcy-
cle an d can lead to chain slip-
pa ge or b reakag e. To prevent
this from occurrin g, keep the
d rive chain slack within the
specifie d limits.
[ECA10572]
EAU78831
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. 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.
1. Drive chain slackDrive chain slack:40.0–50.0 mm (1.57–1.97 in)
1
1. Brake pedal free play adjusting nut
2. Brake torque rod nut
1. Axle nut
2. Drive chain slack adjusting nut
3. Drive chain puller locknut
4. Drive chain puller
1
2
4 31
2
(a)(b)
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Periodic maintenance an d a djustment
6-25
6 4. Place the motorcycle on the cen-
terstand.
5. To tighten the drive chain, turn the drive chain slack adjusting nut at
each end of the swingarm in direc-
tion (a). To loosen the drive chain,
turn the adjusting nut at each end
of the swingarm in direction (b),
and then push the rear wheel for-
ward.
TIPUsing the alignment marks on each
drive chain puller, make sure that both
drive chain pullers are in the same po-
sition 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. Adjust the brake pedal free play. (See page 6-21.)
WARNING
EWA10661
After a djustin g the brake pe dal free
play, check the operation of the
b rake li ght.9. Make sure that the drive chain
pullers are in the same position,
the drive chain slack is correct,
and the drive chain moves
smoothly.
EAU23018
Cleanin g an d lu bricatin g the
d rive chainThe 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.NOTICE
ECA10584
The drive chain must be lu bricated
after washin g the motorcycle, ri din g
in the rain or ri din g in wet areas.1. Remove all dirt and mud from the
drive chain with a brush or cloth.TIPFor a thorough cleaning, have a
Yamaha dealer remove the drive chain and soak it in solvent.2. Spray Yamaha chain lubricant or other suitable chain lubricant on
the entire chain, making sure that
all side plates and rollers have
been sufficiently oiled.
1. Washer
2. Alignment marks
1
2
Tightenin g torques:
Locknut: 7 N·m (0.7 kgf·m, 5.1 lb·ft)
Axle nut:
90 N·m (9.0 kgf·m, 65 lb·ft)
Brake torque rod nut: 18 N·m (1.8 kgf·m, 13 lb·ft)
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Periodic maintenance an d a djustment
6-34
6
4. Disconnect the headlight coupler,
then remove the headlight bulb
cover.
5. Unhook the headlight bulb holder, then remove the burnt-out bulb. 6. Place a new headlight bulb into
position, then secure it with the
bulb holder.
7. Install the headlight bulb cover, then connect the headlight cou-
pler.
8. Place the headlight unit in its orig- inal position, and then tighten the
headlight unit stay bolt to the
specified torque.
9. Install the bolt on each side.
10. Place the headlight unit side cov- ers in their original position, and
then install the screw on each
side.
11. Have a Yamaha dealer adjust the headlight beam if necessary.
EAU45226
Replacin g the auxiliary li ght
b ul b If the auxiliary light bulb burns out, re-
place it as follows.
1. Remove the headlight unit. (See page 6-33.)
2. Remove the auxiliary light bulb socket (together with the bulb) by
pulling it out.
3. Remove the burnt-out bulb by pulling it out.
4. Insert a new bulb into the socket.
5. Install the socket (together with the bulb) by pushing it in.
6. Install the headlight unit.
1. Headlight coupler
2. Headlight bulb holder
1. Headlight bulb holder
2. Headlight bulb
1 21
2
Ti
ghtenin g torque:
Headlight unit stay bolt: 7 N·m (0.7 kgf·m, 5.1 lb·ft)
1. Auxiliary light bulb
2. Auxiliary light bulb socket
1
2
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Periodic maintenance an d a djustment
6-37
6 3. Place the vehicle on the center-
stand, and then remove the axle
nut.
4. Pull the wheel axle out, and then remove the wheel. NOTICE: Do
not apply the b rake after the
wheel an d b rake disc have b een
remove d, otherwise the brake
pa ds will be forced shut.
[ECA11073]
To install the front wheel
1. 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 into the caliper.
2. Insert the wheel axle, and then in-stall the axle nut.
3. Take the vehicle off the center- stand so that the front wheel is on
the ground, and then put the side-
stand down.
4. Tighten the axle nut to the speci- fied torque.
5. Push down hard on the handlebar several times to check for proper
fork operation.
EAU25081
Rear wheel
EAU78751
To remove the rear wheel
WARNING
EWA10822
To avoi d injury, securely support the
vehicle so there is no dan ger of it
fallin g over.1. Take the motorcycle off the cen-
terstand so that the rear wheel is
on the ground, and then put the
sidestand down.
2. Loosen the axle nut.
3. Disconnect the brake torque rod from the brake shoe plate by re-
moving the nut and the bolt.
1. Wheel axle
1
Tightenin g torque:
Axle nut: 59 N·m (5.9 kgf·m, 43 lb·ft)
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Periodic maintenance an d a djustment
6-38
6
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 nut on both ends of the
swingarm.
6. Place the motorcycle on the cen- terstand.
7. Remove the axle nut and the washer, then pull the wheel axle
together with the washer out from
the right side, and then remove
the collars.
TIPA rubber mallet may be useful to tap
the wheel axle out.8. Push the wheel forward, and thenremove the drive chain from the
rear sprocket.
1. Axle nut
1
1. Brake pedal free play adjusting nut
2. Brake camshaft lever
3. Drive chain puller locknut
4. Drive chain slack adjusting nut
5. Brake shoe plate
6. Brake rod
7. Brake torque rod
8. Brake torque rod bolt
9. Brake torque rod nut
234
5
67
1
98
1. Washer
2. Collar
3. Wheel axle
2
1
2
31
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Periodic maintenance an d a djustment
6-39
6
TIPThe drive chain does not need to be
disassembled in order to remove and
install the wheel.9. Remove the wheel.
To install the rear wheel 1. Install the drive chain onto the rear sprocket.
2. Install the wheel by installing the collars on both sides and installing
the washer and the wheel axle
from the right side.
3. Install the washer and the axle nut.
4. Connect the brake rod to 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 the nut.
6. Adjust the drive chain slack. (See page 6-24.)
7. Take the motorcycle off the cen- terstand so that the rear wheel is
on the ground, and then put the
sidestand down. 8. Adjust the brake pedal free play.
(See page 6-21.)
WARNING
EWA10661
After a djustin g the brake pe dal free
play, check the operation of the
b rake li ght.
EAU25853
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, do
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
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