2002 YAMAHA DT125R air filter

PERIODIC MAINTENANCE AND
MINOR REPAIR ................................................ 6-1
Owner’s tool kit ............................................... 6-1
Periodic maintenance and lubrication chart ... 6-2
Removing and installing cowlings .................. 6-5
Removing and installing panels ...................... 6-7
Checking the spark plug ................................. 6-9
Transmission oil ........................................... 6-10
Coolant ......................................................... 6-12
Changing the coolant ................................... 6-14
Cleaning the air filter element........................ 6-16
Adjusting the carburetor ............................... 6-17
Adjusting the engine idling speed ................ 6-17
Adjusting the throttle cable free play ............ 6-18
Tires ............................................................. 6-19
Spoke wheels ............................................... 6-21
Adjusting the clutch lever free play ............... 6-22
Adjusting the brake lever free play ............... 6-23
Adjusting the brake pedal position ............... 6-23
Adjusting the rear brake light switch ............. 6-24
Checking the front and rear brake pads ....... 6-24
Checking the brake fluid level ...................... 6-25
Changing the brake fluid .............................. 6-26
Drive chain slack .......................................... 6-27
Lubricating the drive chain ........................... 6-28
Checking and lubricating the cables ............. 6-29Checking and lubricating the
throttle grip and cable ................................ 6-29
Adjusting the Autolube pump ....................... 6-30
Checking and lubricating the brake and
shift pedals ................................................ 6-30
Checking and lubricating the brake and
clutch levers .............................................. 6-30
Checking and lubricating the sidestand ....... 6-31
Checking the front fork ................................. 6-31
Checking the steering ................................... 6-32
Checking the wheel bearings ....................... 6-32
Battery .......................................................... 6-33
Replacing the fuse ....................................... 6-35
Replacing the headlight bulb ........................ 6-36
Replacing a turn signal light bulb ................. 6-37
Replacing the tail/brake light bulb ................ 6-38
Supporting the motorcycle ............................ 6-39
Front wheel ................................................... 6-39
Rear wheel ................................................... 6-42
Troubleshooting ............................................ 6-43
Troubleshooting charts ................................. 6-44
MOTORCYCLE CARE AND STORAGE ........... 7-1
Care ................................................................ 7-1
Storage ........................................................... 7-4
TABLE OF CONTENTS6
7
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2-1
EAU00026
DESCRIPTION
2
1. Headlight (page 6-36)
2. Radiator cap (page 6-14)
3. Fuel cock (page 3-9)
4. Air filter element (page 6-16)
5. Coolant reservoir tank (page 6-12)6. Helmet holder (page 3-12)
7. Starter (choke) lever (page 3-10)
8. Shift pedal (page 3-4, 5-2)
9. YEIS (page 3-14)
10. YPVS (page 3-14)
1
23 4 5 6
7 8
9 10
Left view
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6-2
PERIODIC MAINTENANCE AND MINOR REPAIR
6
NO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING (× 1,000 km)
ANNUAL
CHECK
1 6 12 18 24
1
*Fuel line•Check fuel hoses for cracks or damage.√√√√ √
2 Spark plug•Replace.√√√√ √
3 Air filter element•Clean.√√
•Replace.√√
4*Battery•Check electrolyte level and specific gravity.
•Make sure that the breather hose is properly routed.√√√√ √
5 Clutch•Check operation.
•Adjust.√√√√√
6*Front brake•Check operation, fluid level and vehicle for fluid leakage.
(See NOTE on page 6-4.)√√√√√ √
•Replace brake pads.Whenever worn to the limit
7*Rear brake•Check operation, fluid level and vehicle for fluid leakage.
(See NOTE on page 6-4.)√√√√√ √
•Replace brake pads.Whenever worn to the limit
8*Brake hoses•Check for cracks or damage.√√√√ √
•Replace. (See NOTE on page 6-4.)Every 4 years
EAU03686
Periodic maintenance and lubrication chart
NOTE:
8The annual checks must be performed every year, except if a kilometer-based maintenance is performed instead.
8From 30,000 km, repeat the maintenance intervals starting from 6,000 km.
8Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools, data and
technical skills.
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6-4
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU03884
NOTE:
8The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
8Hydraulic brake service
9Regularly check and, if necessary, correct the brake fluid level.
9Every two years replace the internal components of the brake master cylinders and calipers, and change the
brake fluid.
9Replace the brake hoses every four years and if cracked or damaged.21
*Carburetor•Check starter (choke) operation.
•Adjust engine idling speed.√√√√√ √
22*Autolube pump•Check operation.
•Bleed if necessary.√√√√
23 Transmission oil•Check oil level.√√√√√ √
•Change.√√
24*Cooling system•Check coolant level and vehicle for coolant leakage.√√√√ √
•Change.Every 3 years
25*Front and rear brake
switches•Check operation.√√√√√ √
26 Moving parts and cables•Lubricate.√√√√ √
27*Lights, signals and
switches•Check operation.
•Adjust headlight beam.√√√√√ √ NO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING (× 1,000 km)
ANNUAL
CHECK
1 6 12 18 24
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6-16
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU04233
Cleaning the air filter
elementThe air filter element should be
cleaned at the intervals specified in
the periodic maintenance and lubrica-
tion chart. Clean the air filter element
more frequently if you are riding in
unusually wet or dusty areas.
1. Remove panel A. (See page 6-8
for panel removal and installation
procedures.)
2. Remove the air filter case cover
by removing the screws.
1
2
1. Screw (×3)
2. Air filter case cover
4. Remove the wing nut, and then
separate the air filter element
from the guide.
5. Remove the sponge material
from the frame, clean it with sol-
vent, and then squeeze the
remaining solvent out.
6. Apply oil of the recommended
type to the entire surface of the
sponge material, and then
squeeze the excess oil out.NOTE:
The sponge material should be wet
but not dripping.
12
3
4
1. Air filter element guide
2. Air filter element frame
3. Sponge material
4. Wing nut
3. Remove the air filter element
from the case.
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6-17
PERIODIC MAINTENANCE AND MINOR REPAIR
67. Pull the sponge material over the
frame.
8. Install the air filter element onto
the guide, and then tighten the
wing nut.
9. Insert the air filter element into
the case.
10. Install the air filter case cover by
installing the screws.
11. Install the panel.
EC000082
cC8Make sure that the air filter ele-
ment is properly seated in the
air filter case.
8The engine should never be
operated without the air filter
element installed, otherwise
the piston and/or cylinder may
become excessively worn.
EAU00632
Adjusting the engine idling
speedThe engine idling speed must be
checked and, if necessary, adjusted
as follows at the intervals specified in
the periodic maintenance and lubrica-
tion chart.
1. Start the engine and warm it up
for several minutes at 1,000–
2,000 r/min while occasionally
revving it to 4,000–5,000 r/min.NOTE:
The engine is warm when it quickly
responds to the throttle.2. Check the engine idling speed
and, if necessary, adjust it to
specification by turning the throt-
tle stop screw.
EAU00629
Adjusting the carburetorThe 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
described in the following section,
however, may be serviced by the
owner as part of routine mainte-
nance.
EC000094
cCThe carburetor has been set and
extensively tested at the Yamaha
factory. Changing these settings
without sufficient technical knowl-
edge may result in poor perfor-
mance of or damage to the engine.
Recommended oil:
2-stroke engine oil
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8-1
EAU01038
SPECIFICATIONS
8
Specifications
Model DT125R
Dimensions
Overall length 2,170 mm
2,235 mm (N, S, SF, CH, A only)
Overall width 830 mm
Overall height 1,255 mm
Seat height 885 mm
Wheel base 1,415 mm
Ground clearance 315 mm
Minimum turning radius 2,100 mm
Basic weight (with oil and
full fuel tank)127 kg
129 kg (CH, A only)
Engine
Engine type Liquid-cooled 2-stroke
Cylinder arrangement Forward-inclined single
cylinder
Displacement 124 cm
3
Bore ×Stroke 56.0 ×50.7 mm Compression ratio 6.7:1
Starting system Kickstarter
Lubrication system Separate lubrication
(Yamaha Autolube)
Engine oil (2-cycle)
Type 2-stroke engine oil
Capacity
Total amount 1.2 L
Transmission oil
Type SAE 10W30 type SE motor oil
Capacity
Periodic oil change 0.75 L
Total amount 0.8 L
Cooling system capacity
(total amount)0.92 L
Air filterWet type element
Fuel
Type REGULAR UNLEADED
GASOLINE ONLY
Fuel tank capacity 10 L
Reserve amount 1.8 L
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