Yamaha a rep- utation for dependability. Please take the time to read this manual thoroughly, so as to enjoy all advantages of your DT125R. The owner’s manual does not only instruct you in how to operate, inspect and maintain your motorcy- cle, but also in how to safeguard yourself and others from trouble and injury.
8 This manual should be considered a permanent part of this motorcycle and should remain with it even if the motorcycle is subsequently sold. 8 Yamaha continually seeks advancements in product design and quality. Therefore, while this manual contains the most current product information available at the time of printing, there may be minor discrepancies between your motorcycle and this manual.
IMPORTANT MANUAL INFORMATION EW000002 PLEASE READ THIS MANUAL CAREFULLY AND COMPLETELY BEFORE OPERATING THIS MOTORCYCLE.
EAU00009 TABLE OF CONTENTS GIVE SAFETY THE RIGHT OF WAY ....1-1 Kickstarter ............ 3-10 Steering lock ..........3-10 DESCRIPTION ..........2-1 Seat .............. 3-11 Left view ............2-1 Helmet holder ..........3-12 Right view ............2-2 Adjusting the shock absorber assembly ..3-12 Controls and instruments .......
TABLE OF CONTENTS PERIODIC MAINTENANCE AND Checking and lubricating the MINOR REPAIR ..........6-1 throttle grip and cable ........ 6-29 Owner’s tool kit ..........6-1 Adjusting the Autolube pump ....... 6-30 Periodic maintenance and lubrication chart ... 6-2 Checking and lubricating the brake and Removing and installing cowlings ....
TABLE OF CONTENTS SPECIFICATIONS ..........8-1 Conversion table ..........8-5 CONSUMER INFORMATION ......9-1 Identification numbers ........9-1 Key identification number ....... 9-1 Vehicle identification number ......9-1 Model label ............. 9-2...
EAU00021 Q GIVE SAFETY THE RIGHT OF WAY Motorcycles 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.
3. If the warning light does not This indicator light flashes when the All electrical systems are supplied come on, have a Yamaha dealer turn signal switch is pushed to the left with power, and the engine can be check the electrical circuit.
INSTRUMENT AND CONTROL FUNCTIONS NOTE: Only for the German model equipped with a speed limiter: The speed limiter prevents the motor- cycle from exceeding a riding speed of 80 km/h. 1. Speedometer unit 1. Tachometer 2. Odometer 2. Red zone 3.
INSTRUMENT AND CONTROL FUNCTIONS EAU03889 Turn signal switch “4/6” To signal a right-hand turn, push this switch to “6”. To signal a left-hand turn, push this switch to “4”. When released, the switch returns to the center position. To cancel the turn signal lights, push the switch in after it has returned to the center position.
INSTRUMENT AND CONTROL FUNCTIONS 1. Engine stop switch “#/$” 1. Clutch lever 1. Shift pedal EAU03890 EAU00155 EAU00157 Clutch lever Shift pedal Engine stop switch “#/$” Set this switch to “#” before starting The clutch lever is located at the left The shift pedal is located on the left the engine.
INSTRUMENT AND CONTROL FUNCTIONS 1. Brake lever 1. Brake pedal 1. Fuel tank cap 2. Unlock. EAU00158 EAU00162 3. Open. Brake lever Brake pedal EAU00177 The brake lever is located at the right The brake pedal is on the right side Fuel tank cap handlebar grip.
INSTRUMENT AND CONTROL FUNCTIONS To install the fuel tank cap 1. Insert the fuel tank cap into the tank opening with the key insert- ed in the lock, and then turn the cap 1/3 turn clockwise. 2. Turn the key 1/4 turn clockwise, and then remove it.
The exhaust system is hot after EAU00185 operation. Make sure that the exhaust system has cooled down Your Yamaha engine has been Immediately wipe off spilled fuel before doing any maintenance designed to use regular unleaded with a clean, dry, soft cloth, since work.
INSTRUMENT AND CONTROL FUNCTIONS EC000114 Recommended oil: Yamalube 2 or equivalent The following precautions must be 2-stroke engine oil (JASO observed to prevent a fire hazard grade “FC”, or ISO grades or other damages. or “EG-D”) 8 Use only unleaded gasoline. Oil quantity: The use of leaded gasoline will 1.2 L...
INSTRUMENT AND CONTROL FUNCTIONS OFF: closed position ON: normal position RES: reserve position FUEL FUEL FUEL 1. Arrow mark positioned over “OFF” 1. Arrow mark positioned over “ON” 1. Arrow mark positioned over “RES” EAU03050 Fuel cock With the lever in this position, fuel This indicates reserve.
INSTRUMENT AND CONTROL FUNCTIONS 1. Starter (choke) lever “1” 1. Kickstarter 1. Steering lock cover 2. Steering lock EAU03839 EAU00212 EAU02934 Starter (choke) lever “1” Kickstarter Steering lock Starting a cold engine requires a rich- To start the engine, fold out the kick- To lock the steering er air-fuel mixture, which is supplied starter lever, move it down lightly with...
INSTRUMENT AND CONTROL FUNCTIONS To unlock the steering 1. Open the steering lock cover, and then insert the key. 2. Push the key in, turn it 1/8 turn counterclockwise that moves out, and then release it. 3. Remove the key, and then close the lock cover.
INSTRUMENT AND CONTROL FUNCTIONS EAU03591 Adjusting the shock absorber assembly This shock absorber assembly is equipped with spring preload adjusting nut. EC000015 Never attempt to turn an adjusting mechanism beyond the maximum 1. Open. 1. Locknut 2. Adjusting nut or minimum settings. EAU00261 Adjust the spring preload as follows.
Minimum (soft): this will result in poor damp- Distance A = 235 mm ing performance. Standard: 8 Always have a Yamaha dealer Distance A = 230 mm service the shock absorber. Maximum (hard): Distance A = 220 mm 3-13...
Improper installation of or damage to YPVS (Yamaha Power Valve any part of the YEIS (Yamaha 8 Do not exceed the load limit of System). This system boosts engine Energy Induction System) will result 2 kg for the carrier. performance and efficiency by means in poor performance.
Therefore, check this system key in the “ON” position. regularly as described below and EC000024 have a Yamaha dealer repair it if it does not function properly. If the YPVS does not operate, have a Yamaha dealer check it.
Periodically check the operation of the ignition circuit cut-off system according to the following procedure. EW000045 If a malfunction is noted, have a Yamaha dealer check the system before riding. 3-16...
5. Push the kickstarter lever down. Does the engine start? The neutral switch may be defective. The motorcycle should not be ridden until checked by a Yamaha dealer. With the engine still running: 6. Move the sidestand up. 7. Keep the clutch lever pulled.
• If necessary, add recommended coolant to specified level. 6-12–6-15 • Check cooling system for leakage. • Check operation. • If soft or spongy, have Yamaha dealer bleed hydraulic system. • Check lever free play. Front brake • Adjust if necessary.
• Adjust if necessary. • Make sure that operation is smooth. Throttle grip • Check free play. 6-18, 6-29 • If necessary, have Yamaha dealer make adjustment or lubricate. • Make sure that operation is smooth. Control cables 6-29 • Lubricate if necessary.
• Correct if necessary. • Check operation of ignition circuit cut-off system. Sidestand switch 3-15–3-17 • If system is defective, have Yamaha dealer check vehicle. • Check fluid level. Battery 6-33–6-35 • Fill with distilled water if necessary.
OPERATION AND IMPORTANT RIDING POINTS EAU01258 4. Turn the starter (choke) on and Starting a warm engine completely close the throttle. Follow the same procedure as for (See page 3-10 starter starting a cold engine with the excep- (choke) operation.) tion that the starter (choke) is not 5.
OPERATION AND IMPORTANT RIDING POINTS EC000048 EAU02937 EAU00424 Recommended shift points Tips for reducing fuel (for Switzerland only) consumption 8 Even with the transmission in The recommended shift points during Fuel consumption depends largely on the neutral position, do not acceleration are shown in the table your riding style.
1,000 km. The various parts in engine at one set throttle posi- in period, immediately have a the engine wear and polish them- tion. Yamaha dealer check the vehi- selves to the correct operating clear- cle. ances. During this period, prolonged 500–1,000 km...
OPERATION AND IMPORTANT RIDING POINTS EAU00458 Parking When parking, stop the engine, remove the key from the main switch, and then turn the fuel cock lever to “OFF”. EW000058 8 Since the engine and exhaust system can become very hot, park in a place where pedestri- ans or children are not likely to touch them.
If you do not have the tools or experi- Periodic inspection, adjustment and ence required for a particular job, lubrication will keep your vehicle in have a Yamaha dealer perform it for the safest and most efficient condi- you. tion possible. The most important...
8 The annual checks must be performed every year, except if a kilometer-based maintenance is performed instead. 8 From 30,000 km, repeat the maintenance intervals starting from 6,000 km. 8 Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools, data and technical skills.
PERIODIC MAINTENANCE AND MINOR REPAIR ODOMETER READING (× 1,000 km) ANNUAL ITEM CHECK OR MAINTENANCE JOB CHECK • Check runout, spoke tightness and for damage. √ √ √ √ Wheels • Tighten spokes if necessary. • Check tread depth and for damage. •...
PERIODIC MAINTENANCE AND MINOR REPAIR 1. Cowling A 1. Cowling C 1. Screw (×2) 2. Cowling B EAU01534 Refer to this section each time a EAU01065 Cowling A Removing and installing cowling needs to be removed and To remove the cowling cowlings installed.
PERIODIC MAINTENANCE AND MINOR REPAIR 1. Screw (×3) EAU01534 To install the cowling To install the cowling Cowling B Place the cowling in the original posi- Place the cowling in the original posi- To remove the cowling tion, and then install the screws. tion, and then install the screws.
PERIODIC MAINTENANCE AND MINOR REPAIR 1. Screw (×3) 1. Panel A EAU01534 EAU01122 To install the cowling Removing and installing Cowling C Place the cowling in the original posi- panels To remove the cowling tion, and then install the screws. Remove the cowling screws, and The panels shown above need to be then pull the cowling off as shown.
PERIODIC MAINTENANCE AND MINOR REPAIR 1. Panel B 1. Screw 1. Screw 2. Panel A 2. Panel B Refer to this section each time a EAU04003 To install the panel panel needs to be removed and Panels A and B Place the panel in the original posi- installed.
Instead, shown, with the spark plug The spark plug is an important have a Yamaha dealer check the wrench included in the owner’s engine component, which is easy to motorcycle. tool kit. check. Since heat and deposits will cause any spark plug to slowly erode, 2.
PERIODIC MAINTENANCE AND MINOR REPAIR EAU04272 Tightening torque: Transmission oil Spark plug: The transmission oil level should be 20 Nm (2.0 m0kgf) checked before each ride. In addition, the transmission oil must be changed NOTE: at the intervals specified in the peri- If a torque wrench is not available odic maintenance and lubrication when installing a spark plug, a good...
PERIODIC MAINTENANCE AND MINOR REPAIR 1. Transmission oil level check window 1. Oil filler cap 1. Transmission oil drain bolt 2. Minimum level mark To change the transmission oil 4. Install the transmission oil drain 3. Wait a few minutes until the oil 1.
PERIODIC MAINTENANCE AND MINOR REPAIR EAU01808 Recommended transmission oil: Coolant See page 8-1. Oil quantity: To check the coolant level Periodic oil change: 1. Place the motorcycle on a level 0.75 L surface and hold it in an upright Total amount (dry transmission): position.
8 If water has been added to the coolant, have a Yamaha dealer check the antifreeze content of the coolant as soon as possi- ble, otherwise the effective- ness of the coolant will be reduced.
PERIODIC MAINTENANCE AND MINOR REPAIR 1. Radiator stopper bolt 1. Coolant drain bolt 1. Reservoir tank hose 2. Radiator cap 4. Place a container under the 5. Disconnect the reservoir tank EAU03101 Changing the coolant engine and remove the coolant hose on the reservoir tank side drain bolt.
NOTE: sion. If any leakage is found, ask a 8 If water has been added to the Yamaha dealer to inspect the cooling coolant, have a Yamaha dealer system. check the antifreeze content of the coolant as soon as possi- 15.
PERIODIC MAINTENANCE AND MINOR REPAIR 1. Screw (×3) 1. Air filter element guide 2. Air filter case cover 2. Air filter element frame 3. Remove the air filter element 3. Sponge material EAU04233 4. Wing nut from the case. Cleaning the air filter 4.
NOTE: NOTE: If the specified idling speed cannot The engine idling speed must be cor- be obtained as described above, rectly adjusted before checking and have a Yamaha dealer make the adjusting the throttle cable free play. adjustment. 6-18...
PERIODIC MAINTENANCE AND MINOR REPAIR EAU04259 8 NEVER OVERLOAD Tire air pressure Tires (measured on cold tires) MOTORCYCLE! Operation of To maximize the performance, dura- Load* Front Rear an overloaded motorcycle may bility, and safe operation of your 125 kPa 150 kPa result in tire damage, loss of Up to 90 kg...
PERIODIC MAINTENANCE AND MINOR REPAIR EAU00681 Tire information This motorcycle is equipped with tube 8 Have a Yamaha dealer replace tires. excessively worn tires. EW000078 Besides being illegal, operat- ing the motorcycle with exces- 8 The front and rear tires should...
PERIODIC MAINTENANCE AND MINOR REPAIR 3. If the specified clutch lever free play could obtained described above, tighten the locknut and skip the rest of the procedure, otherwise proceed as follows. 4. Fully turn the adjusting bolt at the clutch lever in direction a to loosen the clutch cable.
If there is air in the hydraulic sys- and lubrication chart. tem, have a Yamaha dealer bleed the system before operating the motorcycle. Air in the hydraulic 1. Brake light switch system will diminish the braking 2.
EAU03976 REAR Changing the brake fluid fluid. Mixing fluids may result in a Have a Yamaha dealer change the harmful chemical reaction and brake fluid at the intervals specified in lead to poor braking perfor- the NOTE after the periodic mainte- mance.
PERIODIC MAINTENANCE AND MINOR REPAIR EAU00744 Drive chain slack The drive chain slack should be checked before each ride and adjust- ed if necessary. To check the drive chain slack 1. Place the motorcycle on a level surface and hold it in an upright position.
PERIODIC MAINTENANCE AND MINOR REPAIR EAU03006 2. Wipe the drive chain dry. NOTE: Lubricating the drive chain 3. Thoroughly lubricate the drive Make sure that both adjusting plates The drive chain must be cleaned and chain with a special O-ring chain are in the same position for proper lubricated at the intervals specified in lubricant.
Securely support the motorcycle 1. Place the motorcycle on a level Yamaha dealer check or repair it. so that there is no danger of it surface and hold it in an upright falling over. position. 2. While applying the front brake,...
PERIODIC MAINTENANCE AND MINOR REPAIR 3. If the electrolyte is at or below the minimum level mark, add dis- tilled water to raise it to the maxi- mum level mark. 1. Battery 1. Maximum level mark 2. Battery breather hose 2.
PERIODIC MAINTENANCE AND MINOR REPAIR EW000117 8 Take care not to spill elec- To store the battery trolyte on the drive chain, as 1. If the motorcycle will not be used 8 Electrolyte is poisonous and this may weaken it, shorten more than month,...
Replacing the fuse 4. If the fuse immediately blows The fuse holder is located behind again, have a Yamaha dealer panel B. (See page 6-8 for panel check the electrical system. removal and installation procedures.) If the fuse is blown, replace it as fol- lows.
PERIODIC MAINTENANCE AND MINOR REPAIR 1. Bolt (×2) 1. Headlight coupler 1. Headlight bulb holder 2. Headlight bulb cover EAU01158 4. Remove the headlight bulb hold- 3. Disconnect the headlight cou- Replacing the headlight bulb er by turning it counterclockwise, pler, and then remove the head- If the headlight bulb burns out, and then remove the defective...
PERIODIC MAINTENANCE AND MINOR REPAIR 7. Install the headlight unit by installing the bolts. 8. Install the cowling. 9. Have a Yamaha dealer adjust the headlight beam if necessary. a. Do not touch this area. 1. Screw 2. Lens EW000119 3.
PERIODIC MAINTENANCE AND MINOR REPAIR ECA00065 EC000108 Do not overtighten the screw, oth- Do not overtighten the screws, erwise the lens may break. otherwise the lens may break. 1. Screw (×2) 2. Lens 3. Bulb EAU01623 Replacing the tail/brake light bulb 1.
8 It is advisable to have a stand is not available, by placing Yamaha dealer service the a jack under the frame in front of wheel. the rear wheel.
PERIODIC MAINTENANCE AND MINOR REPAIR ECA00048 Do not apply the brake after the wheel has been removed together with the brake disc, otherwise the brake pads will be forced shut. 1. Speedometer cable 1. Speedometer gear unit 2. Axle holder nut (×4) EAU03555 3.
PERIODIC MAINTENANCE AND MINOR REPAIR 7. After tightening the holder nuts, while applying the front brake, push down on the handlebars several times to check if the front fork compress and rebounds smoothly. 8. Connect the speedometer cable. 1. Retainer a.
5. Push the wheel forward, and then remove the drive chain from 8 It is advisable to have a the rear sprocket. Yamaha dealer service the wheel. NOTE: 8 Securely support the motorcy- The drive chain does not need to be...
Use only genuine Yamaha replace- fied torques. ment parts. Imitation parts may look like Yamaha parts, but they are often Tightening torques: inferior, have a shorter service life Axle nut: and can lead to expensive repair 90 Nm (9.0 m0kgf)
Open throttle half-way and start Wipe clean with dry cloth and correct Wet. spark gap or replace spark plug. the engine. Remove spark plug and check electrodes. Engine doesn’t start, ask a Yamaha Dry. Ask a Yamaha dealer to inspect. dealer to inspect. 6-44...
Restart the engine. If the engine overheats again, ask a Level is OK. Yamaha dealer to inspect and repair the cooling system. NOTE: If it is difficult to get the recommended coolant, tap water can be temporarily used, provided that it is changed to the rec- ommended coolant as soon as possible.
EAU03521 MOTORCYCLE CARE AND STORAGE Before cleaning Cleaning Care 1. Cover the muffler outlet with a ECA00010 While the open design of a motorcy- plastic bag after the engine has cle reveals the attractiveness of the 8 Avoid using strong acidic cooled down.
MOTORCYCLE CARE AND STORAGE 8 Do not use any harsh chemical 8 For motorcycles equipped After riding in the rain, near the sea products on plastic parts. Be with a windshield: Do not use or on salt-sprayed roads sure to avoid using cloths or strong cleaners hard...
8 Before operating the motorcy- removed through polishing.) NOTE: cle test its braking perfor- 4. To prevent corrosion, it is recom- Consult a Yamaha dealer for advice mance and cornering behav- mended to apply a corrosion pro- on what products to use. ior.
MOTORCYCLE CARE AND STORAGE Long-term a. Remove the spark plug cap Storage Before storing your motorcycle for and spark plug. Short-term several months: b. Pour a teaspoonful of engine Always store your motorcycle in a 1. Follow all the instructions in the oil into the spark plug bore.
MOTORCYCLE CARE AND STORAGE 6. Lubricate all control cables and NOTE: the pivoting points of all levers Make any necessary repairs before and pedals as well as of the storing the motorcycle. sidestand/centerstand. 7. Check and, if necessary, correct the tire air pressure, and then lift the motorcycle so that both of its wheels ground.
EAU01038 SPECIFICATIONS Specifications Compression ratio 6.7:1 Model DT125R Starting system Kickstarter Dimensions Lubrication system Separate lubrication Overall length 2,170 mm (Yamaha Autolube) 2,235 mm (N, S, SF, CH, A only) Engine oil (2-cycle) Overall width 830 mm Type 2-stroke engine oil...
SPECIFICATIONS Carburetor Chassis Manufacturer MIKUNI Frame type Semi double cradle Model × quantity TM28SS × 1 Caster angle 27°30’ Spark plug Trail 113 mm Manufacturer/model NGK / BR9ES Tire NGK / BR8ES (CH, A only) Front Spark plug gap 0.7–0.8 mm Type With tube Clutch type...
SPECIFICATIONS 90 kg load–maximum Rear load* Type Single disc brake Front 150 kPa (1.50 kgf/cm , 1.50 bar) Operation Right foot operation Rear 175 kPa (1.75 kgf/cm , 1.75 bar) Fluid DOT 4 Off-road riding Suspension Front 125 kPa (1.25 kgf/cm , 1.25 bar) Front Telescopic fork...
SPECIFICATIONS Battery Type GM3-3B Voltage, capacity 12 V, 3 AH Headlight type Conventional incandescent bulb Bulb voltage, wattage × quantity 12 V, 45/40 W × 1 Headlight 12 V, 5/21 W × 1 Tail/brake light 12 V, 21 W × 2 Front turn signal light 12 V, 21 W ×...
SPECIFICATIONS EAU03941 Conversion table CONVERSION TABLE Conver s i o n t a bl e All specification data in this manual are listed in SI and METRIC TO IMPERIAL METRIC UNITS. Metric unit Multiplier Imperial unit m • kgf 7.233 ft •...
Record the key identification number, vehicle identification number and model label information in the spaces provided below for assistance when ordering spare parts from a Yamaha dealer or for reference in case the vehicle is stolen. 1. Key identification number 1.
CONSUMER INFORMATION 1. Model label EAU03757 Model label The model label is affixed to the loca- tion shown. Record the information on this label in the space provided. This information will be needed when ordering spare parts from a Yamaha dealer.
YAMAHA MOTOR CO., LTD. PRINTED ON RECYCLED PAPER PRINTED IN JAPAN 2001·6–0.3×1(E)