Yamaha DT125R- Manuals

1-1 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 motorcycledoes not ignore the laws of physics. Regular care and maintenance are essential for preserving your moto...

EAU00026 DESCRIPTION 1 2 3 4 5 6 7 8 9 2-1 1 2 3 4 5 6 7 8 9 10 Left view 1. Headlight (page 6-33) 2. Radiator cap (page 6-13) 3. Fuel cock (page 3-9) 4. Air filter (page 6-15) 5. Coolant reservoir tank (page 6-13) 6. Helmet holder (page 3-12) 7. Starter (choke) (page 3-10) 8. Shift pedal (page 3-5,...

DESCRIPTION 1 2 3 4 5 6 7 8 9 2-2 11 12 13 14 15 Right view 11. Tool kit (page 6-1) 12. Fuse (page 6-33) 13. Engine oil tank (page 3-9) 14. Rear brake pedal (page 3-6, 6-22) 15. Rear shock absorber spring preload adjusting nut (page 3-13) 3MB-9-E7 12/27/00 2:52 PM Page 11

1 2 3 4 5 6 7 8 9 DESCRIPTION 2-3 16. Clutch lever (page 3-5, 6-21) 17. Left handlebar switches (page 3-4) 18. Speedometer (page 3-3) 19. Coolant temperature gauge (page 3-4) 20. Tachometer (page 3-3) 21. Right handlebar switches (page 3-5) 22. Front brake lever (page 3-6, 6-27) 23. Throttle grip (p...

3-1 ON OFF EAU00028 Main switch The main switch controls the ignitionand lighting systems. Its operation isdescribed below. EAU00036 ONElectrical circuits are switched on.The engine can be started. The keycannot be removed in this position. EAU00038 OFFAll electrical circuits are switched off.The ke...

EAU00075 Oil level indicator circuit check 3-2 INSTRUMENT AND CONTROL FUNCTIONS 1 2 3 4 5 6 7 8 9 Turn the main switch to “ON”. Put the transmission in neutral. Oil level indicator lightdoes not come on. Ask a Yamaha dealer toinspect electrical circuit. Oil level indicator lightcomes on. Oil level i...

3-3 INSTRUMENT AND CONTROL FUNCTIONS 1 2 3 4 5 6 7 8 9 1 2 1. Tachometer 2. Red zone EAU00102 Tachometer This model is equipped with atachometer so the rider can monitorthe engine speed and keep it withinthe ideal power range. EC000003 c C Do not operate in the red zone.Red zone: 10,500 r/min and ab...

3-4 INSTRUMENT AND CONTROL FUNCTIONS 1 2 3 4 5 6 7 8 9 EAU00127 Turn signal switchTo signal a right-hand turn, push theswitch to “ 6 ”. To signal a left-hand turn, push the switch to “ 4 ”. Once the switch is released it will return tothe center position. To cancel the sig-nal, push the switch in af...

3-5 INSTRUMENT AND CONTROL FUNCTIONS 1 2 3 4 5 6 7 8 9 1 1. Engine stop switch EAU00138 Engine stop switchThe engine stop switch is a safetydevice for use in an emergency suchas when the motorcycle overturns orif trouble occurs in the throttle sys-tem. Turn the switch to “ # ” to start the engine. I...

3-6 INSTRUMENT AND CONTROL FUNCTIONS 1 2 3 4 5 6 7 8 9 1 1. Front brake lever EAU00158 Front brake lever The front brake lever is located onthe right handlebar. Pull it toward thehandlebar to apply the front brake. 1 1. Rear brake pedal EAU00162 Rear brake pedal The rear brake pedal is on the rights...

3-7 INSTRUMENT AND CONTROL FUNCTIONS 1 2 3 4 5 6 7 8 9 NOTE:The tank cap cannot be reinstalledunless it is unlocked. The key mustremain in the cap until the cap isproperly installed and locked onto thefuel tank. EW000023 w Be sure the cap is properlyinstalled and locked in placebefore riding the mot...

3-8 INSTRUMENT AND CONTROL FUNCTIONS 1 2 3 4 5 6 7 8 9 EW000130 w Do not overfill the fuel tank. Avoidspilling fuel on the hot engine. Donot fill the fuel tank above the bot-tom of the filler tube or it mayoverflow when the fuel heats uplater and expands. EAU00185 c C Always wipe off spilled fuel im...

3-9 INSTRUMENT AND CONTROL FUNCTIONS 1 2 3 4 5 6 7 8 9 EC000114 c C The following must be observed toprevent a fire hazard or other dam-ages. 8 8 Use only unleaded gasoline.Use of leaded gasoline willcause unrepairable damage tothe catalytic converter. 8 8 Never park this motorcycle inan area that w...

3-10 INSTRUMENT AND CONTROL FUNCTIONS 1 2 3 4 5 6 7 8 9 ON FUEL RES OFF 1 ON 1. Arrow mark positioned “ON” ONWith the lever in this position, fuelflows to the carburetor. Normal ridingis done with the lever in this position. ON: normal position a b 1 RESThis indicates reserve. If you run outof fuel ...

3-11 INSTRUMENT AND CONTROL FUNCTIONS 1 2 3 4 5 6 7 8 9 1 EAU00212 Kick starter Rotate the kick starter away from theengine. Push the starter down lightlywith your foot until the gears engage,then kick smoothly and forcefully tostart the engine. This model has aprimary-coupled kick starter so theeng...

3-12 INSTRUMENT AND CONTROL FUNCTIONS 1 2 3 4 5 6 7 8 9 To install 1. Insert the projections on the front of the seat into the holders, thentighten the seat bolts. 2. Install the panels. NOTE:Make sure that the seat is securelyfitted. 1 EAU00261 Helmet holder To open the helmet holder, insert thekey...

3-15 INSTRUMENT AND CONTROL FUNCTIONS 1 2 3 4 5 6 7 8 9 EC000023 c C The Y.P.V.S. was set at theYamaha factory after many tests. Ifthe settings are disturbed bysomeone without sufficient techni-cal knowledge, poor engine perfor-mance and damage may result. The Y.P.V.S. operation can be heardin the f...

4-1 EAU01114 PRE-OPERATION CHECKS 1 2 3 4 5 6 7 8 9 Owners are personally responsible for their vehicle’s condition. Your motorcycle’s vital functions can start to deterioratequickly and unexpectedly, even if it remains unused (for instance, if it is exposed to the elements). Any damage, fluidleak o...

5-1 1 2 3 4 5 6 7 8 9 EAU00373 w 8 8 Before riding this motorcycle,become thoroughly familiarwith all operating controls andtheir functions. Consult aYamaha dealer regarding anycontrol or function that you donot thoroughly understand. 8 8 Never start your engine or letit run for any length of time i...

5-3 OPERATION AND IMPORTANT RIDING POINTS 1 2 3 4 5 6 7 8 9 1. Turn the fuel cock to “ON”.2. Turn the main switch to “ON” and the engine stop switch to “ # ”. 3. Shift the transmission into neu- tral. NOTE:When the transmission is in neutral,the neutral indicator light should beon. If the light does...

5-4 OPERATION AND IMPORTANT RIDING POINTS 1 2 3 4 5 6 7 8 9 EAU00423 Shifting The transmission lets you control theamount of power you have availableat a given speed for starting, acceler-ating, climbing hills, etc. The use ofthe shift pedal is shown in the illustra-tion.To shift into neutral, depre...

1,000 km and beyond Full throttle can be used. EC000053 c C 8 8 Never let engine speeds enterthe red zone. 8 8 If any engine trouble shouldoccur during the break-in peri-od, consult a Yamaha dealerimmediately. EAU00458 Parking When parking the motorcycle, stopthe engine and remove the ignitionkey. T...

6-1 EAU00462 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 EAU00464 Periodic inspection, adjustment andlubrication will keep your motorcyclein the safest and most efficient condi-tion possible. Safety is an obligationof the motorcycle owner. The mainte-nance and lubrication schedule charts...

6-3 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 EAU03686 Periodic maintenance and lubrication chart NOTE: 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...

6-5 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 EAU03884 NOTE: 8 The air filter needs more frequent service if you are riding in unusually wet or dusty areas. 8 Hydraulic brake service 9 Regularly check and, if necessary, correct the brake fluid level. 9 Every two years replace the inter...

6-6 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 1 2 1 1 EAU01065 Cowling removal andinstallation The cowlings indicated in the illustra-tion need to be removed to performsome of the maintenance describedin this chapter.Refer to this section each time acowling has to be removed or rein-st...

6-7 PERIODIC MAINTENANCE AND MINOR REPAIR 6 1 1. Screw ( × 3) EAU01534* Cowling B To removeRemove the screws and pull outwardas shown. To installPlace in the original position andinstall the screws. To installPlace in the original position andinstall the screws. 3MB-9-E7 12/27/00 2:52 PM Page 43

6-8 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 1 1 EAU01534* Cowling C To removeRemove the screws and pull outwardas shown. 1. Screw ( × 3) 1. Panel D To installPlace in the original position andinstall the screws. EAU01122 Panel removal and installation The panels illustrated need to b...

6-10 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 1 EAU01833 Spark plug Removal 1. Remove the spark plug cap. 2. Use the spark plug wrench in the tool kit to remove the spark plugas shown. InspectionThe spark plug is an importantengine component and is easy toinspect. The condition of the...

6-11 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 Spark plug gap: 0.7 ~ 0.8 mm Tightening torque: Spark plug: 20 Nm (2.0 m 0 kg) 1 3 2 EAU03109 Transmission oil Oil level inspection 1. Place the motorcycle on a level place and hold it in an uprightposition. Warm up the engine forseveral m...

6-12 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 5. Fill the engine with sufficient oil to reach the specified level.Install the oil filler cap and tight-en it. EC000079 c C Do not put in any chemical addi-tives. Transmission oil also lubri-cates the clutch and additivescould cause clutc...

6-13 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 EAU01808 Cooling system 1. Remove panel D. (See page 6-9 for panel removal and installationprocedures.) 2. Check the coolant level in the reservoir tank when the engine iscold as the coolant level will varywith engine temperature. Thecoola...

6-15 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 EC000080 c C Hard water or salt water is harmfulto the engine. You may use dis-tilled water if you can’t get softwater. 10. Install the radiator cap.11. Run the engine several minutes. Stop the engine and recheck thecoolant level in the ra...

6-16 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 6. Insert the air filter guide into the air filter and install it in the case. 7. Install the air filter case cover and panel by installing thescrews. EC000082 c C 8 8 Make sure the air filter is prop-erly seated in the air filtercase. 8 8...

6-17 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 b a 1 EAU00632 Idle speed adjustment 1. Start the engine and warm it up for a few minutes at approxi-mately 1,000 to 2,000 r/min.Occasionally rev the engine to4,000 to 5,000 r/min. The engineis warm when it quickly respondsto the throttle....

6-18 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 EAU00652 Tires To ensure maximum performance,long service and safe operation, notethe following:Tire air pressureAlways check and adjust the tirepressure before operating the motor-cycle. EW000082 w Tire inflation pressure should bechecked...

6-20 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 EAU00685 Wheels To ensure maximum performance,long service, and safe operation, notethe following: 8 Always inspect the wheelsbefore a ride. Check for cracks,bends or warpage of the wheel.Be sure the spokes are tight andundamaged. If any a...

6-24 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 8 Use only the designated qualitybrake fluid. Otherwise, the rub-ber seals may deteriorate, caus-ing leakage and poor brake per-formance. NOTE:If DOT 4 is not available, DOT 3 canbe used. EAU00732 Inspecting the brake fluidlevel Insufficie...

6-25 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 EAU00742 Brake fluid replacement The brake fluid should be replacedonly by trained Yamaha service per-sonnel. Have the Yamaha dealerreplace the following componentsduring periodic maintenance or whenthey are damaged or leaking: 8 oil seals...

6-26 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 EC000096 c C Too little chain slack will overloadthe engine and other vital parts.Keep the slack within the specifiedlimits. 3. Tighten the wheel axle nut to the specified torque. EAU01533* Drive chain slack adjustment 1. Loosen the wheel ...

6-27 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 EC000097 c C Be sure to oil the chain after wash-ing the motorcycle or riding in therain. EAU02962 Cable inspection and lubrication EW000112 w Damage to the outer housing ofcables may lead to internal rustingand interfere with the cable mo...

6-28 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 EAU00774 Autolube pump adjustment The autolube pump is a vital part ofthe engine and requires very sophisti-cated adjustment.Adjusting should be left to a Yamahadealer who has the professionalknowledge and experience to do so. EAU02984 Bra...

6-29 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 EAU02986 Sidestand lubrication Lubricate the sidestand pivoting pointand metal-to-metal contact surfaces.Check that the sidestand moves upand down smoothly. EW000113 w If the sidestand does not movesmoothly, consult a Yamaha deal-er. Recom...

6-30 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 EAU00794 Steering inspection Periodically inspect the condition ofthe steering. Worn out or loose steer-ing bearings may be dangerous.Place a stand under the engine toraise the front wheel off the ground.Hold the lower end of the front for...

6-32 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 Replenishing the battery fluidA poorly maintained battery will cor-rode and discharge quickly. The bat-tery fluid should be checked at leastonce a month. The level should bebetween the minimum level and max-imum level marks. Use only disti...

6-33 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 EAU00804 Fuse replacement If the fuse is blown, turn off the mainswitch and the switch of the circuit inquestion. Install a new fuse of speci-fied amperage. Turn on the switchesand see if the electrical device oper-ates. If the fuse immedi...

6-34 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 3. Remove the headlight connector and the bulb holder cover. 4. Turn the bulb holder counter- clockwise to remove it and thenremove the defective bulb. EW000119 w Keep flammable products and yourhands away from a bulb while it ison, as it ...

6-36 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 1 2 2 1. Disc cover 2. Screw ( × 2) EAU00898 Front wheel removal EW000122 w 8 8 It is advisable to have aYamaha dealer service thewheel. 8 8 Securely support the motorcy-cle so there is no danger of itfalling over. 1. Remove the disc cover...

6-37 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 3 2 1 3. Elevate the front wheel by plac- ing a suitable stand under theengine. 4. Loosen the wheel axle holder nuts. 5. Remove the wheel axle and the front wheel. Make sure themotorcycle is properly supported. NOTE:Do not depress the brak...

6-38 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 1 1 1. Swingarm end bolt ( × 2) EAU03105 Rear wheel removal EW000122 w 8 8 It is advisable to have aYamaha dealer service thewheel. 8 8 Securely support the motorcy-cle so there is no danger of itfalling over. 1. Loosen the rear axle nut.2...

6-39 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 EAU03106 Rear wheel installation 1. Install the rear wheel and chain. Guide the brake disc betweenthe brake pads. Make sure thereis enough gap between thebrake pads before inserting thebrake disc. 2. Make sure the wheel axle is inserted fr...

6-40 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 EAU03108 Troubleshooting charts EW000125 w Never check the fuel system while smoking or in the vicinity of an open flame. Check if there is fuel 1. Fuel Enough fuel. No fuel. Go to compression check. Supply fuel. Engine doesn’t start, go t...

6-41 PERIODIC MAINTENANCE AND MINOR REPAIR 1 2 3 4 5 6 7 8 9 4. Engine overheating EW000070 w Do not remove the radiator cap when the engine and radiator are hot. Scalding hot fluid and steam may beblown out under pressure, which could cause serious injury. Open the radiator cap as follows. Wait unt...

7-1 EAU01518 MOTORCYCLE CARE AND STORAGE 1 2 3 4 5 6 7 8 9 Care The exposure of its technologymakes a motorcycle charming butalso vulnerable. Although high-qualitycomponents are used, they are notall rust-resistant. While a rustyexhaust pipe may remain unnoticedon a car, it does look unattractive on...

7-2 MOTORCYCLE CARE AND STORAGE 1 2 3 4 5 6 7 8 9 8 8 Improper cleaning can damagewindshields, cowlings, panelsand other plastic parts. Useonly a soft, clean cloth orsponge with mild detergentand water to clean plastic. 8 8 Do not use any harsh chemicalproducts on plastic parts. Besure to avoid usin...

7-3 MOTORCYCLE CARE AND STORAGE 1 2 3 4 5 6 7 8 9 After cleaning 1. Dry the motorcycle with a chamois or an absorbing cloth. 2. Immediately dry the drive chain and lubricate it to prevent it fromrusting. 3. Use a chrome polish to shine chrome, aluminum and stainless-steel parts, including the exhaus...

7-4 MOTORCYCLE CARE AND STORAGE 1 2 3 4 5 6 7 8 9 Storage Short-termAlways store your motorcycle in acool, dry place and, if necessary, pro-tect it against dust with a porouscover. ECA00014 c C 8 8 Storing the motorcycle in apoorly ventilated room or cov-ering it with a tarp while it isstill wet wil...

7-5 MOTORCYCLE CARE AND STORAGE 1 2 3 4 5 6 7 8 9 6. Lubricate all control cables and the pivoting points of all leversand pedals as well as of thesidestand/centerstand. 7. Check and, if necessary, correct the tire air pressure, then raisethe motorcycle so that both of itswheels are off the ground.A...

8-1 1 2 3 4 5 6 7 8 9 EAU01038 SPECIFICATIONS Specifications Model DT125R Dimensions Overall length 2,170 mm2,235 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 o...

8-5 1 2 3 4 5 6 7 8 9 SPECIFICATIONS EAU01064 HOW TO USE THE CONVERSION TABLE All specification data in this manual are listed in SI andMETRIC UNITS.Use this table to convert METRIC unit data to IMPERIAL unit data. Ex. METRIC MULTIPLIER IMPERIAL ** mm × 0.03937 = ** in 2 mm × 0.03937 = 0.08 in METRI...

1 2 3 4 5 6 7 8 9 9-1 EAU01039 CONSUMER INFORMATION 1 1 EAU02944 Identification numberrecords Record the key identification number,vehicle identification number andmodel label information in the spacesprovided for assistance when order-ing spare parts from a Yamaha deal-er or for reference in case t...

PRINTED ON RECYCLED PAPER PRINTED IN JAPAN 2000·12–0.4 × 1(E) ! OWNER’S MANUAL 3MB-28199-E7 DT125R YAMAHA MOTOR CO., LTD.