2005 YAMAHA DT125R engine oil

To clean the air filter element
1. Remove panel E. (See page 6-6.)
2. Remove the air filter case cover
by removing the screws.
3. Pull the air filter element out.
1. Guide
2. Filter
4. Remove the sponge material
from the air filter element frame,
clean it with solvent, and then
squeeze the remaining solvent
out.5. Apply oil of the recommended
type to the entire surface of the
sponge material, and then sque-
eze the excess oil out.
NOTE:
The sponge material should be wet
but not dripping.
Recommended oil:
Foam air filter oil
6. Pull the sponge material over the
air filter element frame.
7. Insert the element into the air fil-
ter case.
ECA10480
CAUTION
Make sure that the air filter ele-
ment is properly seated in the
air filter case.
The engine should never be
operated without the air filter
element installed, otherwise
the piston(s) and/or cylinder(s)
may become excessively worn.
8. Install the air filter case cover by
installing the screws.
9. Install the panel.To clean the air filter check hose
1. Check the hose at the bottom of
the air filter case for accumulated
dirt or water.
2. If dirt or water is visible, remove
the hose, clean it, and then install
it.
EAU21280
Adjusting the carburetor
The carburetor is an important part of
the engine and requires very sophisti-
cated adjustment. Therefore, most
carburetor adjustments should be left
to a Yamaha dealer, who has the
necessary professional knowledge
and experience. The adjustment des-
cribed in the following section, howe-
ver, may be serviced by the owner as
part of routine maintenance.
ECA10550
CAUTION
The carburetor has been set and
extensively tested at the Yamaha
factory. Changing these settings
without sufficient technical know-
ledge may result in poor perfor-
mance of or damage to the engine.
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EAU22960
To adjust the drive chain slack
1. Axle nut
2. Chain tensioner
1. Loosen the axle nut.
2. To tighten the drive chain, turn
the adjusting plate on each side
of the swingarm in direction (a).
To loosen the drive chain, turn
the adjusting plate on each side
of the swingarm in direction (b),
and then push the rear wheel for-
ward.
NOTE:
Make sure that both adjusting plates
are in the same position for proper
wheel alignment.
ECA10570
CAUTION
Improper drive chain slack will
overload the engine as well as
other vital parts of the motorcycle
and can lead to chain slippage or
breakage. To prevent this from
occurring, keep the drive chain
slack within the specified limits.
3. Tighten the axle nut to the speci-
fied torque.
Tightening torque:
Axle nut:
90 Nm (9,0 m•kgf)
EAU23021
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.
ECA10581
CAUTION
The drive chain must be lubricated
after washing the motorcycle and
riding in the rain.
1. Clean the drive chain with kero-
sene and a small soft brush.
ECA11120
CAUTION
To prevent damaging the O-rings,
do not clean the drive chain with
steam cleaners, high-pressure
washers or inappropriate solvents.
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive
chain with a special O-ring chain
lubricant.
ECA11110
CAUTION
Do not use engine oil or any other
lubricants for the drive chain, as
they may contain substances that
could damage the O-rings.
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EAU23100
Checking and lubricating the
cables
The operation of all control cables
and the condition of the cables
should be checked before each ride,
and the cables and cable ends should
be lubricated if necessary. If a cable is
damaged or does not move smoothly,
have a Yamaha dealer check or repla-
ce it.
Recommended lubricant:
Engine oil
EWA10720
s s
WARNING
Damage to the outer sheath may
interfere with proper cable opera-
tion and will cause the inner cable
to rust. Replace a damaged cable
as soon as possible to prevent
unsafe conditions.
EAU23110
Checking and lubricating the
throttle grip and cable
The operation of the throttle grip
should be checked before each ride.
In addition, the cable should be lubri-
cated or replaced at the intervals spe-
cified in the periodic maintenance
chart.
EAU23120
Adjusting the Autolube pump
The Autolube pump is a vital and sop-
histicated component of the engine,
which must be adjusted by a Yamaha
dealer at the intervals specified in the
periodic maintenance and lubrication
chart.
EAU23131
Checking and lubricating the
brake and shift pedals
The operation of the brake and shift
pedals should be checked before
each ride, and the pedal pivots
should be lubricated if necessary.
Recommended lubricant:
Lithium-soap-based grease (all-pur-
pose grease)
EAU23140
Checking and lubricating the
brake and clutch levers
The operation of the brake and clutch
levers should be checked before each
ride, and the lever pivots should be
lubricated if necessary.
Recommended lubricant:
Lithium-soap-based grease (all-pur-
pose grease)
EAU23200
Checking and lubricating the
sidestand
The operation of the sidestand should
be checked before each ride, and the
sidestand pivot and metal-to-metal
contact surfaces should be lubricated
if necessary.
EWA10730
s s
WARNING
If the sidestand does not move up
and down smoothly, have a Yama-
ha dealer check or repair it.
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Recommended lubricant:
Lithium-soap-based grease (all-pur-
pose grease)
EAU23271
Checking the front fork
The condition and operation of the
front fork must be checked as follows
at the intervals specified in the perio-
dic maintenance and lubrication
chart.
To check the condition
EWA10750
s s
WARNING
Securely support the motorcycle so
that there is no danger of it falling
over.
Check the inner tubes for scratches,
damage and excessive oil leakage.To check the operation
1. Place the motorcycle on a level
surface and hold it in an upright
position.
2. While applying the front brake,
push down hard on the handle-
bars several times to check if the
front fork compresses and
rebounds smoothly.ECA10590
CAUTION
If any damage is found or the front
fork does not operate smoothly,
have a Yamaha dealer check or
repair it.
EAU23280
Checking the steering
Worn or loose steering bearings may
cause danger. Therefore, the opera-
tion of the steering must be checked
as follows at the intervals specified in
the periodic maintenance and lubrica-
tion chart.
1. Place a stand under the engine to
raise the front wheel off the
ground.
EWA10750
s s
WARNING
Securely support the motorcycle so
that there is no danger of it falling
over.
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EAU26000
Care
While the open design of a motorcy-
cle reveals the attractiveness of the
technology, it also makes it more vul-
nerable. Rust and corrosion can
develop even if high-quality compo-
nents are used. A rusty exhaust pipe
may go unnoticed on a car, however,
it detracts from the overall appearan-
ce of a motorcycle. Frequent and pro-
per care does not only comply with
the terms of the warranty, but it will
also keep your motorcycle looking
good, extend its life and optimize its
performance.
Before cleaning
1. Cover the muffler outlet with a
plastic bag after the engine has
cooled down.
2. Make sure that all caps and
covers as well as all electrical
couplers and connectors, inclu-
ding the spark plug cap, are
tightly installed.3. Remove extremely stubborn dirt,
like oil burnt onto the crankcase,
with a degreasing agent and a
brush, but never apply such pro-
ducts onto seals, gaskets, sproc-
kets, the drive chain and wheel
axles. Always rinse the dirt and
degreaser off with water.
Cleaning
ECA10770
CAUTION
Avoid using strong acidic whe-
el cleaners, especially on spo-
ked wheels. If such products
are used on hard-to-remove
dirt, do not leave the cleaner on
the affected area any longer
than instructed. Also, tho-
roughly rinse the area off with
water, immediately dry it, and
then apply a corrosion protec-
tion spray.
Improper cleaning can damage
windshields, cowlings, panels
and other plastic parts. Use
only a soft, clean cloth or spon-
ge with mild detergent and
water to clean plastic.
Do not use any harsh chemical
products on plastic parts. Be
sure to avoid using cloths or
sponges which have been in
contact with strong or abrasive
cleaning products, solvent or
thinner, fuel (gasoline), rust
removers or inhibitors, brake
fluid, antifreeze or electrolyte.
Do not use high-pressure was-
hers or steam-jet cleaners sin-
ce they cause water seepage
and deterioration in the follo-
wing areas: seals (of wheel and
swingarm bearings, fork and
brakes), electric components
(couplers, connectors, instru-
ments, switches and lights),
breather hoses and vents.
For motorcycles equipped with
a windshield: Do not use strong
cleaners or hard sponges as
they will cause dulling or scrat-
ching. Some cleaning com-
pounds for plastic may leave
scratches on the windshield.
Test the product on a small hid-
den part of the windshield to
make sure that it does not lea-
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ve any marks. If the windshield
is scratched, use a quality
plastic polishing compound
after washing.
After normal use
Remove dirt with warm water, a mild
detergent, and a soft, clean sponge,
and then rinse thoroughly with clean
water. Use a toothbrush or bottle-
brush for hard-to-reach areas. Stub-
born dirt and insects will come off
more easily if the area is covered with
a wet cloth for a few minutes before
cleaning.
After riding in the rain, near the sea or
on salt-sprayed roads
Since sea salt or salt sprayed on
roads during winter are extremely
corrosive in combination with water,
carry out the following steps after
each ride in the rain, near the sea or
on salt-sprayed roads.
NOTE:
Salt sprayed on roads in the winter
may remain well into spring.
1. Clean the motorcycle with cold
water and a mild detergent, after
the engine has cooled down.
ECA10790
CAUTION
Do not use warm water since it
increases the corrosive action of
the salt.
2. Apply a corrosion protection
spray on all metal, including
chrome- and nickel-plated, surfa-
ces to prevent corrosion.
After cleaning
1. Dry the motorcycle with a cha-
mois or an absorbing cloth.
2. Immediately dry the drive chain
and lubricate it to prevent it from
rusting.
3. Use a chrome polish to shine
chrome, aluminum and stainless-
steel parts, including the exhaust
system. (Even the thermally indu-
ced discoloring of stainless-steel
exhaust systems can be removed
through polishing.)4. To prevent corrosion, it is recom-
mended to apply a corrosion pro-
tection spray on all metal, inclu-
ding chrome- and nickel-plated,
surfaces.
5. Use spray oil as a universal clea-
ner to remove any remaining dirt.
6. Touch up minor paint damage
caused by stones, etc.
7. Wax all painted surfaces.
8. Let the motorcycle dry comple-
tely before storing or covering it.
EWA10930
s s
WARNING
Make sure that there is no oil or
wax on the brakes or tires. If
necessary, clean the brake
discs and brake linings with a
regular brake disc cleaner or
acetone, and wash the tires
with warm water and a mild
detergent.
Before operating the motorcy-
cle test its braking performan-
ce and cornering behavior.
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ECA10800
CAUTION
Apply spray oil and wax spa-
ringly and make sure to wipe
off any excess.
Never apply oil or wax to any
rubber and plastic parts, but
treat them with a suitable care
product.
Avoid using abrasive polishing
compounds as they will wear
away the paint.
NOTE:
Consult a Yamaha dealer for advice
on what products to use.
EAU26150
Storage
Short-term
Always store your motorcycle in a
cool, dry place and, if necessary, pro-
tect it against dust with a porous
cover.
ECA10810
CAUTION
Storing the motorcycle in a
poorly ventilated room or cove-
ring it with a tarp, while it is still
wet, will allow water and humi-
dity to seep in and cause rust.
To prevent corrosion, avoid
damp cellars, stables (because
of the presence of ammonia)
and areas where strong chemi-
cals are stored.
Long-term
Before storing your motorcycle for
several months:
1. Follow all the instructions in the
“Care” section of this chapter.
2. For motorcycles equipped with a
fuel cock that has an “OFF” posi-
tion: Turn the fuel cock lever to
“OFF”.
3. Drain the carburetor float cham-
ber by loosening the drain bolt;
this will prevent fuel deposits
from building up. Pour the drai-
ned fuel into the fuel tank.4. Fill up the fuel tank and add fuel
stabilizer (if available) to prevent
the fuel tank from rusting and the
fuel from deteriorating.
5. Perform the following steps to
protect the cylinder, piston rings,
etc. from corrosion.
a. Remove the spark plug cap and
spark plug.
b. Pour a teaspoonful of engine oil
into the spark plug bore.
c. Install the spark plug cap onto
the spark plug, and then place
the spark plug on the cylinder
head so that the electrodes are
grounded. (This will limit sparking
during the next step.)
d. Turn the engine over several
times with the starter. (This will
coat the cylinder wall with oil.)
e. Remove the spark plug cap from
the spark plug, and then install
the spark plug and the spark plug
cap.
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DimensionsOverall length
DT125RE 2210 mm
DT125X 2139 mm
Overall width
795 mm
Overall height
DT125RE 1200 mm
DT125X 1121 mm
Seat height
DT125RE 900 mm
DT125X 886 mm
Wheelbase
DT125RE 1415 mm
DT125X 1396 mm
Ground clearance
DT125RE 300 mm
DT125X 271 mm
Minimum turning radius
DT125RE 2100 mm
DT125X 2016 mm
WeightWith oil and fuel
DT125RE 126.0 kg
DT125X 134.0 kg
EngineEngine type
Liquid cooled 2-stroke
Cylinder arrangement
Forward-inclined single cylinder
Displacement
124.0 cm
3
Bore x stroke
56.0 x 50.7 mmCompression ratio
6.70 :1
Starting system
Electric starter
Lubrication system
Separate lubrication (Yamaha autolube)
Type
YAMALUBE 2-cycle oil or 2-stroke engine
oil (JASO FC g
Engine oil quantityQuantity
1.3 L
Transmission oilType
SAE10W30 type SE motor oil
Oil change quantity
0.75 L
Cooling systemCoolant reservoir capacity (up to the maxi-
mum leve
0.30 L
Radiator capacity (including all routes)
0.92 L
Air filterAir filter element
Wet element
FuelRecommended fuel
Regular unleaded gasoline only
Fuel tank capacity
10.7 L
Fuel reserve amount
1.8 L
CarburetorManufacturer
MIKUNI
Type x quantity
TM28-92 x1
Spark plug(s)Manufacturer/model
NGK/BR8ES
Spark plug gap
0.7-0.8 mm
Clutch type
Wet, multiple-disc
TransmissionPrimary reduction system
Helical gear
Primary reduction ratio
71/22 (3.227)
Secondary reduction system
Chain drive
Secondary reduction ratio
57/16 (3.563)
Transmission type
Constant mesh 6-speed
Operation
Left foot operation
Gear ratio1st
34/12 (2.833)
2nd
30/16 (1.875)
3rd
24/17 (1.412)
4th
24/21 (1.143)
8
SPECIFICATIONS
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