2002 YAMAHA DT125R maintenance

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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1-1
EAU00021
QGIVE SAFETY THE RIGHT OF WAY
1Motorcycles are fascinating vehicles, which can give you an unsurpassed feeling of power and free-
dom. However, they also impose certain limits, which you must accept; even the best motorcycle
does not ignore the laws of physics.
Regular care and maintenance are essential for preserving value and operating condition of your
motorcycle. Moreover, what is true for the motorcycle is also true for the rider: good performance
depends on being in good shape. Riding under the influence of medication, drugs and alcohol is, of
course, out of the question. Motorcycle riders—more than car drivers—must always be at their mental
and physical best. Under the influence of even small amounts of alcohol, there is a tendency to take
dangerous risks.
Protective clothing is as essential for the motorcycle rider as seat belts are for car drivers and passen-
gers. Always wear a complete motorcycle suit (whether made of leather or tear-resistant synthetic
materials with protectors), sturdy boots, motorcycle gloves and a properly fitting helmet. Optimum pro-
tective wear, however, should not encourage carelessness. Although full-coverage helmets and suits,
in particular, create an illusion of total safety and protection, motorcyclists will always be vulnerable.
Riders who lack critical self-control run the risk of going too fast and are apt to take chances. This is
even more dangerous in wet weather. The good motorcyclist rides safely, predictably and defensive-
ly—avoiding all dangers, including those caused by others.
Enjoy your ride! 3MB-9-E8 6/13/01 10:55 AM Page 8

3-7
INSTRUMENT AND CONTROL FUNCTIONS
3
EW000130
w8Do not overfill the fuel tank,
otherwise it may overflow
when the fuel warms up and
expands.
8Avoid spilling fuel on the hot
engine.
EAU00185
cCImmediately wipe off spilled fuel
with a clean, dry, soft cloth, since
fuel may deteriorate painted sur-
faces or plastic parts.
EAU04206
Your Yamaha engine has been
designed to use regular unleaded
gasoline with a research octane num-
ber of 91 or higher. If knocking (or
pinging) occurs, use a gasoline of a
different brand or premium unleaded
fuel. Use of unleaded fuel will extend
spark plug life and reduce mainte-
nance costs.
EAU01084
Catalytic converter(for Switzerland and Austria)
This motorcycle is equipped with a
catalytic converter in the exhaust
chamber.
EW000128
wThe exhaust system is hot after
operation. Make sure that the
exhaust system has cooled down
before doing any maintenance
work.
Recommended fuel:
REGULAR UNLEADED
GASOLINE ONLY
Fuel tank capacity:
Total amount:
10.0 L
Reserve amount:
1.8 L
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6-1
EAU00462
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU00464
Safety is an obligation of the owner.
Periodic inspection, adjustment and
lubrication will keep your vehicle in
the safest and most efficient condi-
tion possible. The most important
points of inspection, adjustment, and
lubrication are explained on the fol-
lowing pages.
The intervals given in the periodic
maintenance and lubrication chart
should be simply considered as a
general guide under normal riding
conditions. However, DEPENDING
ON THE WEATHER, TERRAIN,
GEOGRAPHICAL LOCATION, AND
INDIVIDUAL USE, THE MAINTE-
NANCE INTERVALS MAY NEED TO
BE SHORTENED.
EW000060
wIf you are not familiar with motor-
cycle maintenance work, have a
Yamaha dealer do it for you.
EAU01175
Owner’s tool kitThe owner’s tool kit is located behind
panel B. (See page 6-8 for panel
removal and installation procedures.)
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 pre-
ventive maintenance and minor
repairs. However, additional tools
such as a torque wrench may be nec-
essary to perform certain mainte-
nance work correctly.
1
1. Owner’s tool kit
NOTE:
If you do not have the tools or experi-
ence required for a particular job,
have a Yamaha dealer perform it for
you.
EW000063
wModifications not approved by
Yamaha may cause loss of perfor-
mance and render the vehicle
unsafe for use. Consult a Yamaha
dealer before attempting any
changes.
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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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6-3
PERIODIC MAINTENANCE AND MINOR REPAIR
6
9
*Wheels•Check runout, spoke tightness and for damage.
•Tighten spokes if necessary.√√√√
10*Tires•Check tread depth and for damage.
•Replace if necessary.
•Check air pressure.
•Correct if necessary.√√√√ √
11*Wheel bearings•Check bearing for looseness or damage.√√√√
12*Swingarm•Check operation and for excessive play.√√√√
13 Drive chain•Check chain slack.
•Make sure that the rear wheel is properly aligned.
•Clean and lubricate.Every 500 km and after washing
the motorcycle or riding in the rain.
14*Steering bearings•Check bearing play and steering for roughness.√√√√√
•Lubricate with lithium-soap-based grease.Every 24,000 km
15*Chassis fasteners•Make sure that all nuts, bolts and screws are properly tightened.√√√√ √
16 Sidestand•Check operation.
•Lubricate.√√√√ √
17*Sidestand switch•Check operation.√√√√√ √
18*Front fork•Check operation and for oil leakage.√√√√
19*Shock absorber
assembly•Check operation and shock absorber for oil leakage.√√√√
20*Rear suspension relay
arm and connecting arm
pivoting points•Check operation.√√√√
•Lubricate with lithium-soap-based grease.√√ NO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING (× 1,000 km)
ANNUAL
CHECK
1 6 12 18 24
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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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6-5
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU01065
Removing and installing
cowlingsThe cowlings shown above need to
be removed to perform some of the
maintenance jobs described in this
chapter.
2
1
1. Cowling A
2. Cowling B
EAU01534
Cowling A
To remove the cowlingRemove the cowling screws, and
then pull the cowling off as shown.
1
1. Screw (×2)
Refer to this section each time a
cowling needs to be removed and
installed.
1
1. Cowling C
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