2019 YAMAHA YZF-R125 torque

Instrument and control functions
3-19
3
EAUE3431
Seats
Passenger seat
To remove the passenger seat
1. Remove the plastic cover.
2. Remove the nut and then slide in
forward direction to remove the
passenger seat as shown.
To install the passenger seat
1. Insert the projections on the front
of the passenger seat into the seat
holders as shown, and then place
the seat in the original position.2. Install the passenger seat by in-
stalling and tightening the nut to
the specified torque.
3. Install the plastic cover.
Rider seat
To remove the rider seat
1. Insert the key into the seat lock,
and then turn it clockwise.
2. While holding the key in the posi-
tion “2”, lift from rear of the rider
seat and pull it backward.
1. Plastic cover
1. Nut
1
ZAUE3363
ZAUE3364
1
1. Projection
2. Seat holder
Tightening torque:
Passenger seat nut:
13 N·m (1.3 kgf·m, 9.6 lb·ft)
1. Rider seat lock
2. Unlock.
ZAUE3365
1
2
2
1
ZAUE3366
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Periodic maintenance and adjustment
6-2
6
EAU17303
Emission controls not only function to
ensure cleaner air, but are also vital to
proper engine operation and maximum
performance. In the following periodic
maintenance charts, the services relat-
ed to emissions control are grouped
separately. These services require
specialized data, knowledge, and
equipment. Maintenance, replace-
ment, or repair of the emission control
devices and systems may be per-
formed by any repair establishment or
individual that is certified (if applicable).
Yamaha dealers are trained and
equipped to perform these particular
services.
EAU17362
Owner’s tool kit
The owner’s tool kit is located under
the rider seat. (See page 3-19.)
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.
TIP
If you do not have the tools or experi-
ence required for a particular job, have
a Yamaha dealer perform it for you.
1.
ZAUM1593
1
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Periodic maintenance and adjustment
6-9
6
EAU19623
Checking the spark plug
The spark plug is an important engine
component, which should be checked
periodically, preferably by a Yamaha
dealer. Since heat and deposits will
cause any spark plug to slowly erode,
it should be removed and checked in
accordance with the periodic mainte-
nance and lubrication chart. In addi-
tion, the condition of the spark plug
can reveal the condition of the engine.
The porcelain insulator around the
center electrode of the spark plug
should be a medium-to-light tan (the
ideal color when the vehicle is ridden
normally). If the spark plug shows a
distinctly different color, the engine
could be operating improperly. Do not
attempt to diagnose such problems
yourself. Instead, have a Yamaha deal-
er check the vehicle.
If the spark plug shows signs of elec-
trode erosion and excessive carbon or
other deposits, it should be replaced.
Before installing a spark plug, the
spark plug gap should be measured
with a wire thickness gauge and, if
necessary, adjusted to specification.Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the spark
plug threads.
TIP
If 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.
Specified spark plug:
NGK/MR8E9
1. Spark plug gap
Spark plug gap:
0.8–0.9 mm (0.031–0.035 in)
Tightening torque:
Spark plug:
12.5 N·m (1.25 kgf·m, 9.22 lb·ft)
1
ZAUM0037
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Periodic maintenance and adjustment
6-11
65. Clean the engine oil strainer with
solvent.
TIP
Skip to step 9 when only changing
the oil.
Perform steps 6–8 when replacing
the oil filter element.
6. Remove the oil filter element cover
by removing the bolts.
7. Remove and replace the oil filter
element and O-ring.8. Install the oil filter element cover
by installing the bolts, then tight-
ening them to the specified
torque.
TIP
Make sure that the O-ring is properly
seated.
9. Install the engine oil strainer, com-
pression spring, O-ring and the
engine oil drain bolt, and then
tighten it to the specified torque.
NOTICE: Before installing the
engine oil drain bolt, do not for-
get to install the O-ring, com-
pression spring, and oil strainer
in position.
[ECA10422]
10. Refill with the specified amount of
the recommended engine oil, and
then install and tighten the oil filler
cap.
1. Engine oil drain bolt
2. O-ring
3. Compression spring
4. Strainer
5. Oil pan
1. Bolt
2. Oil filter element cover
2 3 4
51
ZAUE0672
1. Oil filter element
2. O-ring
Tightening torques:
Oil filter element cover bolt:
10 N·m (1.0 kgf·m, 7.4 lb·ft)
Tightening torques:
Engine oil drain bolt:
32 N·m (3.2 kgf·m, 24 lb·ft)
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Periodic maintenance and adjustment
6-26
6 3. Tighten the axle nut, then the lock-
nuts to their specified torques.
4. Make sure that the drive chain
pullers are in the same position,
the drive chain slack is correct,
and the drive chain moves
smoothly.
EAU23026
Cleaning and lubricating the
drive chain
The 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 lubricated
after washing the motorcycle, riding
in the rain or riding in wet areas.
1. Clean the drive chain with kero-
sene and a small soft brush.
NOTICE: To prevent damaging
the O-rings, do not clean the
drive chain with steam cleaners,
high-pressure washers or inap-
propriate solvents.
[ECA11122]
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive
chain with a special O-ring chain
lubricant. NOTICE: Do not use
engine oil or any other lubri-
cants for the drive chain, as they
may contain substances that
could damage the O-rings.
[ECA11112]
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)
UB5GE0E0.book Page 26 Thursday, August 23, 2018 10:05 AM