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EC000096
cCToo little chain slack will overload
the engine and other vital parts.
Keep the slack within the specified
limits.3.Tighten the wheel axle nut to the
specified torque.
EAU01533*
Drive chain slack adjustment1.Loosen the wheel axle nut.
2.To tighten the chain, turn the
chain adjusting plates in direction
a. To loosen the chain, turn the
chain adjusting plates in direction
band push the wheel forward.
Turn each chain adjusting plate
to exactly the same position to
maintain correct axle alignment.
a b
2
1
1.Wheel axle nut
2.Chain adjusting plate
Tightening torque:
Wheel axle nut:
90 Nm (9.0 m
0kg)
EAU03006
Drive chain lubricationThe chain consists of many parts
which work with each other. If the
chain is not maintained properly, it
will wear out quickly. Therefore, the
chain must be serviced regularly.
This service is especially necessary
when riding in dusty areas. This
motorcycle is equipped with a sealed
type chain. Steam cleaning, high-
pressure washers, and solvents can
damage the drive chain, so do not
use these for cleaning it. Use only
kerosene to clean the drive chain.
Wipe it dry, and thoroughly lubricate it
with SAE 30 ~ 50W motor oil. Do not
use any other lubricants on the drive
chain. They may contain solvents
that could damage the sealed chain.
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122
1.Disc cover
2.Screw (´2)
EAU00898
Front wheel removal
EW000122
w8
8
It is advisable to have a
Yamaha dealer service the
wheel.
8 8
Securely support the motorcy-
cle so there is no danger of it
falling over.1.Remove the disc cover.
2.Remove the speedometer cable
from the front wheel side.
EAU01579
Supporting the motorcycleSince the Yamaha DT125R has no
centerstand, follow these precautions
when removing the front and rear
wheel or performing other mainte-
nance requiring the motorcycle to
stand upright. Check that the motor-
cycle is in a stable and level position
before starting any maintenance. A
strong wooden box can be placed
under the engine for added stability.
Front wheel service
To stabilize the rear of the motorcy-
cle, either use a motorcycle stand or
place a motorcycle jack under the
frame in front of the rear wheel to
prevent it from moving from side to
side. Then use a motorcycle stand to
elevate the front wheel off of the
ground.Rear wheel service
Use a motorcycle stand or motorcycle
jack to elevate the motorcycle so the
rear wheel is off the ground.
Alternatively, two jacks can be placed
under the frame or swingarm.
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1.Swingarm end bolt (´2)
EAU03105
Rear wheel removal
EW000122
w8
8
It is advisable to have a
Yamaha dealer service the
wheel.
8 8
Securely support the motorcy-
cle so there is no danger of it
falling over.1.Loosen the rear axle nut.
2.Elevate the rear wheel by placing
a suitable stand under the
engine.
3.Remove the swingarm end bolts.4.Remove the axle nut.
5.Push the wheel forward and
remove the drive chain.
6.Pull out the rear axle and remove
the wheel assembly by pulling
backward.
NOTE:
8Do not depress the brake pedal
when the disc and caliper are
separated.
8You do not have to disassemble
the chain in order to remove or
install the rear wheel.
2
1
1.Axle nut
2.Chain adjusting plate
6.Tighten the axle holder nuts to
the specified tightening torque.
Tighten the upper nuts first and
then lower ones. When tightened
in this sequence, there should be
a gap formed at the bottom of
the axle holder.
7.After tightening the holder nuts,
push down on the handlebars
several times and check if the
fork rebounds smoothly. Tightening torque:
Axle holder nut:
10 Nm (1.0 m
0kg)1
1.Gap
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EAU03106
Rear wheel installation1.Install the rear wheel and chain.
Guide the brake disc between
the brake pads. Make sure there
is enough gap between the
brake pads before inserting the
brake disc.
2.Make sure the wheel axle is
inserted from the left side and
that the chain adjusting plates
are installed with the punched
side outward.
3.Install the swingarm end bolts.
4.Adjust the drive chain.
5.Tighten the following parts to the
specified torques.
Tightening torque:
Axle nut:
90 Nm (9.0 m
0kg)
Swingarm end bolt:
3 Nm (0.3 m0kg)
EAU01008
TroubleshootingAlthough Yamaha motorcycles
receive a rigid inspection before ship-
ment from the factory, trouble may
occur during operation.
Any problem in the fuel, compres-
sion, or ignition systems can cause
poor starting and loss of power. The
troubleshooting chart describes a
quick, easy procedure for making
checks.
If your motorcycle requires any
repair, bring it to a Yamaha dealer.
The skilled technicians at a Yamaha
dealership have the tools, experi-
ence, and know-how to properly ser-
vice your motorcycle. Use only gen-
uine Yamaha parts on your
motorcycle. Imitation parts may look
like Yamaha parts, but they are often
inferior. Consequently, they have a
shorter service life and can lead to
expensive repair bills.
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