YAMAHA YS125 2017 Service Manual

Periodic maintenance an d a djustment
6-6
6
19 Shift pe
dal pivot
shaft • Lubricate with lithium-soap-
based grease. √√√√√
20 *Unifie
d b rake sys-
tem • Check cable free play, and adjust
if necessary. √√√√√√
• Lubricate link pivot of brake pedal with lithium-soap-based grease. √√√√√
21 Si
destan d, center-
stan d • Check operation.
• Lubricate with lithium-soap-
based grease. √√√√√
22 *Sidestan d switch • Check operation and replace if
necessary. √√√√√√
23 *Front fork • Check operation and for oil leak-
age.
• Replace if necessary. √√√√
24 *Shock a
bsor ber as-
sem blies • Check operation and for oil leak-
age.
• Replace if necessary. √√√√
25 En gine oil • Change (warm engine before
draining).
• Check oil level and vehicle for oil leakage. √√√√√√
26 En
gine oil filter ele-
ment •Replace.
√√√
27 *Front an
d rear
b rake switches • Check operation.
√√√√√√
28 *Movin
g parts an d
ca bles • Lubricate.
√√√√√
NO. ITEM CHECK OR MAINTENANCE JOB
OD OMETER READING
ANNUAL
CHECK
1000 km
(600 mi) 6000 km
(3500 mi) 12000 km
(7000 mi) 18000 km
(10500 mi) 24000 km
(14000 mi)
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Periodic maintenance an d a djustment
6-7
6
EAU72690
TIP The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
 Hydraulic brake service
• Regularly check and, if necessary, correct the brake fluid level.
• Every two years replace the internal components of the brake master cylinder and caliper, and change the brake fluid.
• Replace the brake hoses every four years and if cracked or damaged.29 *Throttle
grip hous-
in g an d cab le • Check operation and free play.
• Adjust the throttle cable free play
if necessary.
• Lubricate the throttle grip housing and cable. √√√√√
30 *Li
ghts, si gnals an d
switches • Check operation.
• Adjust headlight beam.
√√√√√√
NO. ITEM CHECK OR MAINTENANCE JOB
ODOMETER READING
ANNUAL
CHECK
1000 km
(600 mi) 6000 km
(3500 mi) 12000 km
(7000 mi) 18000 km
(10500 mi) 24000 km
(14000 mi)UBT4E0E0.book Page 7 Thursday, November 17, 2016 10:55 AM

Periodic maintenance an d a djustment
6-8
6
EAU18724
Removin g an d installin g the
cowlin g an d panelsThe cowling and panels shown need to
be removed to perform some of the
maintenance jobs described in this
chapter. Refer to this section each time
the cowling or a panel needs to be re-
moved and installed.
EAU78741
Cowlin g A
To remove the cowlingRemove the bolt, and then take the
cowling off. To install the cowling
Place the cowling in the original posi-
tion, and then install the bolt.
EAU56050
Panel A
To remove the panel1. Remove the screw.
1. Panel A
1
1. Panel B
2. Cowling A
1. Cowling A
2. Bolt
1
2
12
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Periodic maintenance an d a djustment
6-9
6 2. Pull the front of the panel out, and
then slide the panel forward to re-
lease it in the rear.
To install the panel
1. Secure the rear of the panel, and then push the front of the panel in.
2. Install the screw. Panel B
To remove the panel
1. Slide the panel lock cover open,
insert the key into the lock, and
then turn it 1/4 turn clockwise.
2. Pull the front of the panel out with the key inserted in the lock, and
then slide the panel forward to re-
lease it in the rear. To install the panel
1. Secure the rear of the panel, and
then push the front of the panel in
with the key inserted in the lock.
2. While pushing the panel inward, turn the key counterclockwise to
the original position, remove it,
and then close the panel lock cov-
er.
1. Screw
1
1. Panel B
2. Panel lock cover
3. Unlock.
1
2
3
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Periodic maintenance an d a djustment
6-10
6
EAU78710
Checkin g the spark plugThe spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic main-
tenance and lubrication chart. In addi-
tion, the condition of the spark plug
can reveal the condition of the engine.
To remove the spark plu g
1. Remove cowling A. (See page 6-8.)
2. Remove the Y.R.C.S. (Yamaha Ram-Air Cooling System) cap by
removing the bolts and then, re-
move the spark plug cap. 3. Remove the spark plug as shown,
with the spark plug wrench includ-
ed in the owner’s tool kit. To 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.
1. Cowling A
2. Y.R.C.S (Yamaha Ram–Air Cooling System) cap
3. Bolt
4. Spark plug cap
1. Spark plug wrench
4 32
1
1
Specified
spark plu g:
NGK/CPR8EA-9
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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
6-12
6
ficiently
before removin g the oil
filler cap.
[EWA17640]
NOTICE: Do not
operate the vehicle until you
know that the en gine oil level is
sufficient.
[ECA10012]
TIPThe engine oil should be between the
minimum and maximum level marks.4. If the engine oil is below the mini- mum level mark, add sufficient oil
of the recommended type to raise
it to the correct level.
5. Check the O-ring for damage, and replace it if necessary.
6. Install and tighten the engine oil filler cap.
To chan ge the en gine oil (with or
without oil filter element replace-
ment) 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, the engine oil drain bolt and its
gasket to drain the oil from the
crankcase.
TIPSkip steps 4–6 if the oil filter element is
not being replaced.4. Remove the oil filter element coverby removing the bolts.
1. Engine oil filler cap
1. O-ring
2. Engine oil dipstick
3. Maximum level mark
4. Minimum level mark
1
4 321
1. Engine oil drain bolt
2. Gasket
1. Bolt
2. Oil filter element cover
12
1
2
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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
6-15
6 3. Lightly tap the air filter element to
remove most of the dust and dirt,
and then blow the remaining dirt
out with compressed air as
shown.
TIPReplace the air filter element if it is ex-
cessively worn or damaged.4. Insert the air filter element into theair filter case. NOTICE: Make
sure that the air filter element is
properly seate d in the air filter
case. The en gine shoul d never
b e operated without the air filter
element installe d, otherwise the piston(s) an
d/or cylin der(s) may
b ecome excessively worn.
[ECA10482]
5. Install the air filter case cover by
installing the screws.
6. Install the panel.
To clean the air filter check hose 1. Remove panel A. (See page 6-8.)
2. Check the hose shown for accu- mulated dirt, water or oil. 3. If dirt, water or oil is visible, re-
move the hose, clean it, and then
install it in its original position.
4. Install the panel.
1. Air filter element
1
1. Air filter element
1
1. Air filter check hose
1
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