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Yamaha DT125RE 2005 Service Manual

Summary of DT125RE 2005

  • Page 1

    Service manual dt125re 1d01-ae1 dt125x 2005.

  • Page 2

    Dt125re/x 1d01-1d02/2c81 service manual © 2005 yamaha motor españa, s.A. 1st edition, january 2005 all rights reserved. Any reprinting or unauthorized use without the written permission of yamaha motor españa, s.A. Is expressly prohibited. Printed in spain. Eas00001.

  • Page 3: Notice

    Eas00002 notice this manual was produced by the yamaha motor españa s.A. Primarily for use by yamaha dealers and their qualified mechanics. It is not possible to include all the knowledge of a mechanic in one manual. Therefore, anyone who uses this book to perform maintenance and repairs on yamaha v...

  • Page 4: How to Use This Manual

    Eas00007 how to use this manual this manual is intended as a handy, easy-to-read reference book for the mechanic. Comprehensive explanations of all installation, removal, disassembly, assembly, repair and check procedures are laid out with the individual steps in sequential order. The manual is divi...

  • Page 5

    Eas00008 symbols the following symbols are not relevant to every vehicle. Symbols to indicate the subject of each chapter. General information specifications periodic checks and adjustments chassis engine cooling system carburetor(s) electrical system troubleshooting symbols 10 to 17 indicate the fo...

  • Page 6: Specifications

    Spec 2 specifications chk adj 3 periodic checks and adjustments chas 4 chassis eng 5 engine cool 6 cooling system carb 7 carburetor elec 8 electrical system eas00010 table of contents trbl shtg 9 troubleshooting general information gen info 1.

  • Page 7: Gen

    Gen info.

  • Page 8

    1.

  • Page 9

    Gen info chapter 1 general information motorcycle identification ……………………………………………1-1 frame serial number ……………………………………………………1-1 engine serial number……………………………………………………1-1 important information …………………………………………………1-2 preparation for removal ……………………………………………1-2 all replacement parts ……………………………………...

  • Page 10: General Information

    Gen info motorcycle identifications 1-1 eas00014 general information motorcycle identification frame serial number the frame identification number is stamped onto the steering head pipe. Note: the frame serial number is used to identify the motorcycle and therefore it can be used for the enrollment ...

  • Page 11: Important Information

    Gen info important information 1-2 important information preparation for removal and disassembly 1. Before removal and disassembly, remove all dirt, mud, dust and foreign material. 2. Use only the proper tools and cleaning equipment. Refer to the “special tools”. 3. When disassembling, always keep m...

  • Page 12

    Gen info important information 1-3 eas00024 bearings and oil seals install bearings and oil seals so that the manu- facturer’s marks or numbers are visible. When installing oil seals, lubricate the oil seal lips with a light coat of lithium-soap-based grease. Oil bearings liberally when installing, ...

  • Page 13

    Gen info checking the connections 1-4 eas00026 checking the connections check the leads, couplers, and connectors for stains, rust, moisture, etc. 1. Disconnect: • lead • coupler • connector 2. Check: • lead • coupler • connector moisture dry with an air blower. Rust/stains connect and disconnect se...

  • Page 14: Special Tools

    Gen info special tools 1-5 eas00027 special tools the following special tools are necessary for complete and accurate tune-up and assembly. Use only the appropriate special tools as this will help prevent damage caused by the use of inappro- priate tools or improvised techniques. Special tools, part...

  • Page 15

    Gen info special tools 1-6 tool no. Tool name / usage illustration 90890-01135 crankcase separation tool this tool is used to remove the crankshaft or separate the crankcase. 90890-01274 (1) cranckshaft intalling tool -01275 (2) crankshaft pin -01278 (3) adapter(m12) 90890-01326 t-handle this tool i...

  • Page 17: Spec

    Spec.

  • Page 18

    2.

  • Page 19

    Spec chapter 2 specifications general specifications …………………………………………………2-1 engine specifications……………………………………………………2-4 chassis specifications …………………………………………………2-6 electrical specifications ……………………………………………2-8 conversion table …………………………………………………………2-10 general tightening torque specifications …...

  • Page 20: Specifications

    Spec general specifications 2-1 specifications general specifications model dt125re dt125x model code 1d01/1d02 2c81 dimensions: overall lenght 2210mm 2139mm overall width 795mm 1121mm overall height 1200mm 1200mm seatheight 900mm 886mm wheelbase 1415mm 1396mm minimum ground clearance 300mm 271 mm m...

  • Page 21

    Spec general specifications 2-2 model code 1d01/1d02 2c81 spark plug: type br8es manufacturer ngk spark plug gap 0,7~0,8mm (0,0276~0,03315in) clutch type wet, multiple disc transmission: primary reduction system helical gear primary reduction ratio 71/22(3,227) secondary reduction system chain drive...

  • Page 22

    Spec general specifications 2-3 model code 1d01/1d02 2c81 wheel travel: front wheel travel 270mm(10.63in) 200mm (7,87in) rear wheel travel 260mm(10.24in) 230mm (9.05in) electrical: ignition system cdi charging system ac magneto battery type gt6b-3 capacity 12v 6ah headlight: bulb type bulb wattage x...

  • Page 23

    Spec general specifications 2-4 item standard limit cylinder head: warpage limit * lines indicate 0,03mm straightedge measurement. Cylinder: bore size 56.00~56.02mm *** taper limit 0.05mm *** out of round limit 0.01mm *** piston: piston size “d” 55.950~55.955 *** measurement point* 10mm *** piston t...

  • Page 24

    Spec general specifications 2-5 item standard limit crankshaft: crank width “a” 57.90~57.95mm *** runout limit “c” *** 0.03mm big end side clearance “d” 0.2~0.7mm *** small end free play “e” 0.026~0.040mm *** clutch: friction plate thickness 2.9~3.1mm 2.7mm quantity 7pcs *** clutch plate thickness 1...

  • Page 25

    Spec general specifications 2-6 chassis item standard limit model code 1d0 2c81 1d0 2c81 front wheel: type spoke wheels spoke wheels rim size 21x1.60 17 x 3.00 rim material steel steel front wheel travel: 270mm 270mm max. Radial wheel runout 1mm 1mm max. Lateral wheel runout 0.5mm 0.5mm rear wheel: ...

  • Page 26

    Spec general specifications 2-7 item standard limit model code 1d0 2c81 1d0 2c81 rear suspension: type swingarm swingarm (link suspension) (link suspension) rear shock absorber assemby travel 93mm 87 mm spring free lenght 245mm 250mm installed lenght 230mm 244mm spring preload (spring lenght) hard/s...

  • Page 27

    Gen info general specifications 2-8 electrical model 1d01/1d02 2c81 system voltage 12 v ignition system: ignition system type c.D.I. Ignition timing (b.T.D.C.) ((º)) 17 /1500r/min advancer type digital c.D.I.: magneto model/manufacturer f4fu/yamaha pick up coil resistance((ohm)) 310±20%w/r-w/l sourc...

  • Page 28

    Gen info general specifications 2-9 indicator light neutral indicator light 12v3wx1 turn indicator light 12v3wx1 oil level indicator light 12v3wx1 high beam indicator light 12v3wx1 starting system: system type electric starter starter motor: model/manufacturer 3mb / moric power output 0.2kw armature...

  • Page 29

    Spec conversion table / general tightening torques specifications 2-10 eas00028 conversion table all specification data in this manual are listed in si and metric units. Use this table to convert metric unit data to imperial unit data. Ex. Metric multiplier imperial ** mm x 0.03937 = ** in 2 mm x 0....

  • Page 30

    Spec definition of units 2-11 tightening torques engine tightening thread torque part to be tightened q’ty size nm m•kg remarks spark plug 1 m14x1.25 20 2,0 cylinder head nut 5 m8x1.25 22 2,2 cylinder stud bolt 9 m8x1.25 13 1,3 loctite screw glue nut 4 m8x1.25 28 2,8 power valve holder, valve cover ...

  • Page 31

    Spec definition of units 2-12 chassis tightened thread torque parts to be tightened size nm m•kg remarks engine stay (top) and frame m10 30-35 3,0-3,5 cylinder head stay (top) and frame m10 30-35 3,0-3,5 bottom screw (front) engine and frame m10 60-78 6,0-7,8 bottom screw (front) engine to swingarm ...

  • Page 32

    Spec coolant flow chart 2-13 coolant flow chart water pump crankcase cover crankcase cylinder cylinder head bypass hose thermostatic valve (thermostatic valve) outlet hose radiator inlet hose coolant cold (less than 65°c (149°f)) coolant hot (165°(149°f) or more).

  • Page 33

    Spec lubrication points and lubricant types 2-14 eas00031 engine lubrication points (part name) lubricant type oil seal lips (all) apply lightweight lithium-soap base grease o-rings (all) apply lightweight lithium-soap base grease bearing retainer crankshaft bearings (left and center) apply engine o...

  • Page 34

    Spec lubrication points and lubricant types 2-15 eas00032 chassis lubrication points (part name) lubricant type ball bearing (steering shaft) apply lightweight lithium-soap base grease bearing (steering shafts) apply lightweight lithium-soap base grease oil seal clutch to lever apply lightweight lit...

  • Page 35

    Spec cable routing 2-16 cable routing clutch wire right turn signal lead left turn signal lead throttle cable indicator light wire lead meter wire lead headlight bulb wire handle wire lead (right) a cover with cap after connecting wires. B route the installation between lower brac- ket and headlight...

  • Page 36

    Spec cable routing 2-17 cable routing master cylinder front brake hose wire throttle clutch sw wire lead sw handle wire lead (left) clip a.I.S. Pipe overflow pipe to air filter pipe i license light wire lead oil gauge a turn the hose to obtain the desired angle. B route clutch wire first for the ins...

  • Page 37

    Spec cable routing 2-18 cable routing main switch wire lead pipe overflow ignition coil horn flasher relay air vent hose fuel pipe oil pipe a route speedometer cable to frame guide. B route pipe overflow behind engine holder. C screw ground wire and rectifier with the same bolt. D pipe overflow pass...

  • Page 38

    Spec cable routing 2-19 cable routing front brake hose clutch wire ignition coil throttle wire therm switch sidestand switch wire lead oil hose a route brake hose through the guide. B clamp clutch wire. C guide wire (chassis): sw handle wire lead (r), sw handle wire lead (l), clutch sw wire lead, fr...

  • Page 39: Chk

    Chk adj.

  • Page 40

    3.

  • Page 41

    Chapter 3 periodic checks and adjustments introduction/periodic maintenance/lubrication …………………3-1 engine ……………………………………………………………………………3-2 y.P.V.S. Cable adjustment ………………………………………………3-2 idle speed adjustment …………………………………………………3-3 throttle cable free play adjustment……………………………3-4 carburetor cable f...

  • Page 42

    Chk adj introduction/periodic maintenance/ lubrication intervals 3-1 periodic checks and adjustments note: • the annual checks must be performed every year, except if a kilometer-based maintenance is performed instead. • from 30000 km, repeat the maintenance intervals starting from 6000 km. • items ...

  • Page 43

    Chk adj y.P.V.S. Cable adjustment 3-2 2 1 engine y.P.V.S. Cable adjustment 1. Remove • pulley cover (power valve) 2. Turn on the main switch note if the y.P.V.S. Doesn’t operate, refeer to the “y.P.V.S. System” in chapter 9 3. Check • alignment mark not aligned adjust the y.P.V.S. Cables 4. Adjust •...

  • Page 44

    Chk adj idle speed adjustment 3-3 idle speed adjustment 1. Adjust: • engine idle speed eas00054 adjusting the engine idling speed note: prior to adjusting the engine idling speed, the air filter element should be clean, and the engi- ne should have adequate compression. 1. Start the engine and let i...

  • Page 45

    Chk adj adjusting the throttle cable free play 3-4 eas00058 adjusting the throttle cable free play note: prior to adjusting the throttle cable free play, the engine idling speed and carburetor synch- ronization should be adjusted properly. 1. Check: • throttle cable free play a out of specification ...

  • Page 46

    Chk adj adjusting the throttle cable free play/ carburetor cable free play adjustmen 3-5 carburetor cable free play adjustment note: before adjusting carburetor cable, throttle cable free play should be adjusted. 1. Pull back the adjuster cover. 2. Check: • carburetor cable free play a out of specif...

  • Page 47

    Chk adj autolube pump stroke adjustmen/ autolube pump air bleeding 3-6 autolube pump stroke adjustment 1. Remove: • autolube pump cover 2. Adjusting mark not aligned adjust the autolube pump 3. Adjust • autolube pump the adjusting marks a and b has to match when the throttle cable free play ends. Ad...

  • Page 48

    Chk adj autolube pump air bleeding/ checking the spark plug 3-7 3. Air blled: • pump case and/or oil pipe air bleeding steps • remove the bleed cap • start the engine. • keep the oil running out until air bubbles dissapear. • keep the engine running at about 2.000r/min for two minutes or so • when a...

  • Page 49

    Chk adj checking the spark plug/ checking the ignition timing 3-8 6. Measure: • spark plug gap a (with a wire thickness gauge) out of specification regap. 7. Install: • spark plug note: before installing the spark plug, clean the spark plug and gasket surface. 8. Connect: • spark plug cap eas00064 c...

  • Page 50

    Chk adj checking the ignition timing/ engine oil level inspection 3-9 3. Check: • ignition timing a. Start the engine, warm it up for several minutes, and then let it run at the specified engine idling speed. B. Check that the stationary pointer is within the firing range on the generator rotor. Inc...

  • Page 51

    Chk adj engine oil level inspection 3-10 0 km/h 4 0 6 0 8 0 1 0 0 1 2 0 1 3 0 2 0 y 0 0 0 0 1 5 0 0 0 8 b j z n caution always use the same type of engine oil; mixing oils may result in a harmful chemical reaction and lead to poor performance. “oil” indicator light oil warning light checking method ...

  • Page 52

    Chk adj transmission oil level inspection/ transmission oil replacement 3-11 transmission oil level inspection 1. Inspect: • transmission oil level oil level low add sufficient oil transmission oil level steps: • place the machine on a level surface. • warm up the engine for several minutes and stop...

  • Page 53

    Chk adj transmission oil replacement/ adjusting the clutch cable free play 3-12 5. Install: • drain plug 6. Fill: • crankcase caution • do not add any chemical additives. Transmission oil also lubricates the clutch and additives could cause clutch slippage. • be sure no foreign materials enters the ...

  • Page 54

    Chk adj adjusting the clutch cable free play 3-13 c. Tighten the locknut. Note: if the specified clutch cable free play cannot be obtained on the handlebar side of the cable, use the adjusting nut on the engine side. Engine side a. Loosen the locknuts . B. Turn the adjusting bolt in direction a or b...

  • Page 55

    Chk adj adjusting the clutch cable free play 3-14 7. Disconnect: • autolube pump cable • autolube pump hose refer to the “autolube pump cable and hose” section in the chapter 4. 8. Drain: • transmission oil refer to the ”transmission oil repla- cement” section. 9. Remove: • return spring • bolt (mas...

  • Page 56

    Chk adj adjusting the clutch cable free play 3-15 note: • when installing the crankcase cover, engage the autolube pump drive gear with its driven gear as slowly turn the autolube pump shaft. • tighten the screws (crankcase cover) in stage, using a crisscross pattern. • before installing the brake p...

  • Page 57

    Chk adj adjusting the clutch cable free play/ cleaning the air filter element 3-16 20. Air bleeding: • autolube pump refer to the “autolube pump air blee- ding section. 21. Install: • autolube pump cover eas00089 cleaning the air filter element note: on the bottom of the air filter case is a check h...

  • Page 58

    Chk adj cleaning the air filter element 3-17 caution do not twist the air filter element when squeezing it. 4. Check: • air filter element damage replace. 5. Apply the recommended oil to the entire surface of the air filter element and squeeze out the excess oil. The air filter element should be wet...

  • Page 59

    Chk adj carburetor joint inspections /fuel line inspection/checking the crankcase breather hose 3-18 carburetor joint inspection 1. Inspect: • carburetor joint crack-damage replace refer to the “reed valve” section in chap- ter 7 for replacement 2. Check the tightening torque of the carbure- tor joi...

  • Page 60

    Chk adj exhaust system inspection/engine oil line inspection/ coolant level inspection 3-19 full low exhaust system inspection 1 .Inspect: • gasket (exhaust pipe) • joint (silencer) damage replace exhaust gas leakage repair • exhaust pipe • silencer cracked/dent/damage repair or replace 2. Tighten: ...

  • Page 61

    Chk adj coolant level inspection/ changing the coolant 3-20 s s warning do not remove the radiator cap when the engine is hot. Caution hard water or salt water is harmful to the engine parts; use boiled or distilled water if you can’t get soft water. 4. Add: • soft water (tap water) until the coolan...

  • Page 62

    Chk adj changing the coolant 3-21 tor cap and slowly turn the radiator cap counterclockwise toward the detent to allow any residual pressure to escape. When the hissing sound has stopped, press down on the radiator cap and turn it coun- terclockwise to remove. The following procedure applies to all ...

  • Page 63

    Chk adj changing the coolant 3-22 with soap and water. • if coolant is swallowed, induce vomiting and get immediate medical attention. Caution • adding water instead of coolant lowers the antifreeze content of the coolant. If water is used instead of coolant check, and if necessary, correct the anti...

  • Page 64

    Chk adj cooling system inspection 3-23 cooling system inspection 1. Inspect: • radiator • inlet hose • outlet hose • water outlet pipe cracks-damage replace refer to the “cooling system” section ins chapter 6. 1 4.

  • Page 65

    Chk adj adjusting the front brake/ adjusting the rear brake 3-24 eas00108 chassis adjusting the front brake 1. Check: • brake lever free play out of specification adjust. 2. Adjust: • brake lever free play a. Loosen the locknut . B. Turn the adjusting bolt in direction a or b until the specified bra...

  • Page 66

    Chk adj adjusting the rear brake/ checking the brake fluid level 3-25 2. Adjust: • brake pedal position a. Loosen the locknut . B. Turn the adjusting bolt in direction a or b until the specified brake pedal position is obtained. S s warning after adjusting the brake pedal position, check that the en...

  • Page 67

    3-26 2. Check: • brake fluid level below the minimum level mark add the recommended brake fluid to the proper level. A front brake b rear brake s s warning • use only the designated brake fluid. Other brake fluids may cause the rubber seals to deteriorate, causing leakage and poor brake performance....

  • Page 68

    Chk adj checking the front and rear brake pads/ adjusting the rear brake light switch 3-27 eas00119 checking the front and rear brake pads the following procedure applies to all of the brake pads. 1. Remove: • rubber plug 2. Operate the brake. 3. Check: • front brake pad • rear brake pad wear indica...

  • Page 69

    Chk adj checking the front and rear brake hoses/ adjusting the drive chain slack 3-28 eas00131 checking the front and rear brake hoses the following procedure applies to all of the brake hoses and brake hose clamps. 1. Check: • brake hose cracks/damage/wear replace. 2. Check: • brake hose clamp loos...

  • Page 70

    Chk adj adjusting the drive chain slack 3-29 3. Check: • drive chain slack a out of specification adjust. 4. Remove: • cotter pin 5. Loosen: • wheel axle nut 6. Adjust: • drive chain slack a. Loosen both locknuts. B. Turn both adjusters in direction a or b until the specified drive chain slack is ob...

  • Page 71

    Chk adj lubricating the drive chain/ cheeking and adjusting the steering head 3-30 09*92/61 *0139 vtld e0610 0000000 5 83 db (a ) - 4000 m in- 1 eas00142 lubricating the drive chain the drive chain consists of many interacting parts. If the drive chain is not maintained pro- perly, it will wear out ...

  • Page 72

    Chk adj cheeking and adjusting the steering head 3-31 a. Remove the lock washer , the upper ring nut , and the rubber washer . B. Loosen the lower ring nut and then tigh- ten it to specification with a steering nut wrench. C. Loosen the lower ring nut completely, then tighten it to specification. S ...

  • Page 73

    Chk adj cheeking and adjusting the steering head/ checking the front fork 3-32 6. Measure: • steering head tension note: make sure all of the cables and wires are pro- perly routed. A. Point the front wheel straight ahead. B. Install a plastic locking tie loosely around the end of the handlebar as s...

  • Page 74

    Chk adj checking the front fork/adjusting the rear shock absorber assembly 3-33 2. Check: • inner tube damage/scratches replace. • oil seal oil leakage replace. 3. Hold the motorcycle upright and apply the front brake. 4. Check: • front fork operation push down hard on the handlebar several times an...

  • Page 75

    Chk adj adjusting the rear shock absorber assembly/checking the tires 3-34 2. Tighten: • tighten the locknut eas00164 checking the tires the following procedure applies to both of the tires. 1. Check: • tire pressure out of specification regulate. S s warning • the tire pressure should only be check...

  • Page 76

    Chk adj checking the tires 3-35 s s warning it is dangerous to ride with a worn-out tire. When the tire tread reaches the wear limit, replace the tire immediately. 2. Check: • tire surfaces damage/wear replace the tire. Tire tread depth sidewall s s warning • do not use a tubeless tire on a wheel de...

  • Page 77

    Chk adj checking the tires/ checking and tightening the spokes 3-36 s s warning • new tires have a relatively low grip on the road surface until they have been slightly worn. Therefore, approximately 100 km should be traveled at normal speed before any high-speed riding is done. • after a tire has b...

  • Page 78

    Chk adj checking and tightening the spokes/ checking and lubricating the cables 3-37 2. Tighten: • spoke (with a spoke wrench) note: be sure to tighten the spokes before and after break-in. Eas00170 checking and lubricating the cables the following procedure applies to all of the inner and outer cab...

  • Page 79

    Chk adj lubricating the levers and pedals/lubricating the sidestand/lubricanting the rear suspension 3-38 eas00171 lubricating the levers and pedals lubricate the pivoting point and metal-to- metal moving parts of the levers and pedals. Eas00172 lubricating the sidestand lubricate the pivoting point...

  • Page 80

    Chk adj electrical system 3-39 eas00178 electrical system checking and charging the battery s s warning batteries generate explosive hydrogen gas and contain electrolyte which is made of poisonous and highly caustic sulfuric acid. Therefore, always follow these preventive measures: • wear protective...

  • Page 81

    Chk adj checking and charging the battery 3-40 note: since mf batteries are sealed, it is not possi- ble to check the charge state of the battery by measuring the specific gravity of the electroly- te. Therefore, the charge of the battery has to be checked by measuring the voltage at the battery ter...

  • Page 82

    Chk adj checking and charging the battery 3-41 s s warning do not quick charge a battery. Caution • never remove the mf battery sealing caps. • do not use a high-rate battery charger since it forces a high-amperage current into the battery quickly and can cause battery overheating and battery plate ...

  • Page 83

    Chk adj checking and charging the battery/ checking the fuses 3-42 caution first, connect the positive battery lead , and then the negative battery lead . 8. Check: • battery terminals dirt clean with a wire brush. Loose connection connect properly. 9. Lubricate: • battery terminals 10. Install: • b...

  • Page 84

    Chk adj checking the fuses/ replacing the headlight bulb 3-43 3. Replace: • blown fuse a. Set the main switch to “off”. B. Install a new fuse of the correct amperage rating. C. Set on the switches to verify if the electrical circuit is operational. D. If the fuse immediately blows again, check the e...

  • Page 85

    Chk adj replacing the headlight bulb/ adjusting the headlight beam 3-44 5. Install: • headlight bulbnew secure the new headlight bulb with the headlight bulb holder. Caution avoid touching the glass part of the head- light bulb to keep it free from oil, otherwise the transparency of the glass, the l...

  • Page 86: Chas

    Chas.

  • Page 87

    4.

  • Page 88

    Chapter 4 chassis front wheel …………………………………………………………………4-1 removal ………………………………………………………………………4-2 inspection……………………………………………………………………4-3 installation …………………………………………………………………4-5 rear wheel ……………………………………………………………………4-7 removal ………………………………………………………………………4-8 inspection……………………………………………………………………4-9 ...

  • Page 89: Chassis

    Chas front wheel 4-1 chassis front wheel hub bearing collar oil seal rim spoke cap collar dust cover 10 wheel axle 11 cap 12 gear unit (speedometer) 58 nm (5,8 m • kg, 42ft•lb) dt125re a tire size: 80/90-21 48p b rim size: 21x1.60 c rim runout limit: vertical: 1,0 mm (0,08 in) lateral: 0,5 mm (0,02 ...

  • Page 90

    Chas removing the front wheel 4-2 eas00519 removing the front wheel 1. Stand the motorcycle on a level surface. S s warning securely support the motorcycle so that there is no danger of it falling over. Note: place the motorcycle on a suitable stand so that the front wheel is elevated. 2. Remove: • ...

  • Page 91

    Chas checking the front wheel 4-3 eas00526 checking the front wheel 1. Check: • wheel axle roll the wheel axle on a flat surface. Bends replace. S s warning do not attempt to straighten a bent wheel axle. 2. Check: • tire • front wheel damage/wear replace. Refer to “checking the tires” and “checking...

  • Page 92

    Tire air valve stem locknut 1.5 nm (0.15 m•kg, 1.1 ft•lb) chas checking the front wheel 4-4 6. Check: • collars damage/wear replace. S s warning • after mounting a new tire, ride conserva- tively for a while to become accustomed to the “feel” of the new tire and to allow the tire to seat itself prop...

  • Page 93

    Chas checking the front wheel/ installing the front wheel 4-5 caution do not contact the wheel bearing inner race or balls. Contact should be made only with the outer race. Note: use a socket that matches the diameter of the wheel bearing outer race and oil seal. Eas00542 installing the front wheel ...

  • Page 94

    Chas installing the front wheel 4-6 4. Tighten: • wheel axle • nut (axle holder): s s warning make sure the brake cable is routed pro- perly. Caution before tightening the wheel axle nut, push down hard on the handlebar several times and check if the front fork rebounds smo- othly. 45~70 nm (4.5~7.0...

  • Page 95

    Chas rear wheel 4-7 rear wheel hub collar bearing oil seal rim spoke cap driven sprocket bolt 10 nut 11 collar 12 dust cover 13 collar 14 oil seal 15 chain puller 16 chain puller 17 wheel axle 18 washer 19 nut 20 drive chain 90 nm (9,0 m • kg, 65ft•lb) dt125re a tire size: 110/80-18 58p b rim size: ...

  • Page 96

    Chas removing the rear wheel 4-8 eas00561 removing the rear wheel 1. Stand the motorcycle on a level surface. S s warning securely support the motorcycle so that there is no danger of it falling over. Note: place the motorcycle on a suitable stand so that the rear wheel is elevated. 2. Remove: • rea...

  • Page 97

    Chas inspecting the rear wheel/ installing the rear wheel 4-9 inspecting the rear wheel 1. Inspect: • rear wheel axle refer to the “front wheel - inspec- tion” section. 2. Inspect: • wheel hub • dust covers (bearings) • wheel refer to the “front wheel - inspec- tion” section. 3. Measure: • wheel run...

  • Page 98

    Chas installing the rear wheel 4-10 2. Adjust: • drive chain slack a • refer to the “drive chain slack adjustment” section in chapter 3. 3. Tighten: • wheel axle nut • bolts (swingarm end) drive chain slack: dt125re 40~55mm (1,77~2,16in.) dt125x 25~40mm (0,98~1,58 in.) recommended lubricant lithium-...

  • Page 99

    Chas front and rear brake 4-11 front and rear brake master cylinder cap diaphragm master cylinder kit master cylinder brake hose brake caliper pad spring piston piston seal 10 dust seal 11 brake pad 12 brake disc 26 nm (2,6 m • kg, 19ft•lb) d use new one 6 nm (0,6 m • kg, 4,3ft•lb) 18 nm (1,8 m • kg...

  • Page 100

    Chas front and rear brake 4-12 reservoir tank cap protec- tor reservoir tank cap inner cap diaphragm reservoir tank reservoir hose master cylinder master cylinder kit brake hose 10 brake caliper 11 piston 12 piston seal 13 dust seal 14 shim 15 pad spring 16 brake pads 17 brake disc a brake fluid typ...

  • Page 101

    Chas replacing the front brake pads 4-13 eas00579 caution disc brake components rarely require disassembly. Therefore, always follow these preventive measures: • never disassemble brake components unless absolutely necessary. • if any connection on the hydraulic brake system is disconnected, the ent...

  • Page 102

    Chas replacing the front brake pads 4-14 3. Remove: • brake pads • brake pad springs 4. Measure: • brake pad wear limit a out of specification replace the brake pads as a set. 5. Install: • brake pad springs • brake pads note: always install new brake pads and a new brake pad spring as a set. A. Con...

  • Page 103

    Chas replacing the front brake pads/ replacing the rear brake pads 4-15 6. Lubricate: • retaining bolt caution • do not allow grease to contact the brake pads. • remove any excess grease. 7. Install: • retaining bolt 8. Check: • brake fluid level below the minimum level mark a add the recommended br...

  • Page 104

    Chas replacing the rear brake pads 4-16 1. Remove: • protector (caliper body) • retaining bolt • turn the caliper body counterclockwise 2. Remove: • brake pads • brake pad springs • shim (brake pad) 3. Measure: • brake pad wear limit a out of specification replace the brake pads as a set. 4. Install...

  • Page 105

    Chas replacing the rear brake pads 4-17 5. Lubricate: • retaining bolt (caliper body) 6. Tighten: • retaining bolt (caliper body) 7. Check: • brake fluid level below the minimum level mark add the recommended brake fluid to the proper level. Refer to “checking the brake fluid level” in chapter 3. 8....

  • Page 106

    Chas disassembling the front brake caliper 4-18 eas00618 disassembling the front brake caliper note: before disassembling the brake caliper, drain the brake fluid from the entire brake system. 1. Remove: • union bolt • copper washers • brake hose note: put the end of the brake hose into a container ...

  • Page 107

    Chas disassembling the front brake caliper/ disassembling the rear brake caliper 4-19 a blow compressed air into the brake hose joint opening a to force out the piston from the brake caliper. S s warning • cover the brake caliper piston with a rag. Be careful not to get injured when the piston is ex...

  • Page 108

    Chas disassembling the rear brake caliper 4-20 3. Disconnect the dust boot and then pull out the caliper body from the guide shaft on te caliper bracket . 4. Remove: • rear wheel refer to the “rear wheel” section. • caliper bracket 5. Remove: • caliper piston • dust seal • piston seal a. Blow compre...

  • Page 109

    Chas disassembling the front brake master cylinder 4-21 eas00588 disassembling the front brake master cylinder note: before disassembling the front brake master cylinder, drain the brake fluid from the entire brake system. 1. Remove: • brake switch • brake lever • return spring (brake lever) note: w...

  • Page 110

    Chas disassembling the front brake master cylinder/disassembling the rear brake master cylinder 4-22 5. Remove: • cap (master cylinder) • diaphragm • dust boot • circlip • master cylinder kit note: to collect any remaining brake fluid, place a container under the master cylinder and the end of the b...

  • Page 111

    Chas disassembling the rear brake master cylinder/checking the front and rear brake caliper 4-23 4. Remove: • brake hoses • reservoir tank • circlip • push rod • master cylinder kit 5. Remove: • cap (reservoir tank) • inner cap (reservoir tank) • diaphragm note: to collect any remaining brake fluid,...

  • Page 112

    Chas checking the front and rear brake caliper 4-24 1. Check: • brake caliper piston rust/scratches/wear replace the brake caliper piston. • brake caliper cylinder scratches/wear replace the brake caliper assembly. • brake caliper body cracks/damage replace the brake caliper assembly. • brake fluid ...

  • Page 113

    Chas checking the front and rear brake caliper 4-25 3. Check: • master cylinder wear/scratches replace the caliper assembly. • master cylinder body cracks/damage replace. • oil delivery passage (caliper body) blow out with compressed air. A front b rear 4. Check: • master cylinder kit scratches/wear...

  • Page 114

    Chas checking the front and rear brake caliper 4-26 note: • replace the pad spring as a set if pad replacement is required. • replace the pads as a set if either if found to be worn to the wear limit. 8. Inspect: • brake disc galling/damage replace. 9. Measure: • brake disc deflection out of specifi...

  • Page 115

    Chas assembling and installing the front and rear brake caliper 4-27 assembling and installing the front and rear brake caliper s s warning • before installation, all internal brake components should be cleaned and lubricated with clean or new brake fluid. • never use solvents on internal brake comp...

  • Page 116

    Chas assembling and installing the front and rear brake caliper 4-28 4. Install: • piston seal • dust seal • clip • caliper piston s s warning always use new piston seal and dust seal. Caution install the clip into the slot on the caliper body correctly. 5. Install: • caliper bracket 6. Install: • p...

  • Page 117

    Chas assembling and installing the front and rear brake caliper 4-29 8. Install: • copper washers • brake hose • union bolt caution when installing the brake hoses to the cali- per and master cylinder lightly touch the brake pipe with the projections on them. S s warning • proper hose routing is ess...

  • Page 118

    Chas assembling and installing the front and rear brake caliper 4-30 10. Bleed: • brake system refer to “air bleeding” section. 11. Check: • brake fluid level below the minimum level mark a add the recommended brake fluid to the proper level. Refer to “brake fluid inspection” in chapter 3. ”lower” l...

  • Page 119

    Chas assembling and installing the front and rear brake caliper 4-31 assembling and installing the front and rear brake caliper 1. Install: • master cylinder kit • push rod • circlip • dust boot • brake hoses • cooper washers • union bolt • reservoir tank note: at this time, teporarily tighten the u...

  • Page 120

    Chas assembling and installing the front and rear brake caliper 4-32 note: when installing the caliper piston , be sure to have it’s open end facing the caliper cylinder 4. Install: • caliper bracket • rear wheel refer to the “rear wheel installa- tion” section. Note: be sure the boss on the swingar...

  • Page 121

    Chas assembling and installing the front and rear brake caliper 4-33 7. Install: • cooper washers • brake hose • union bolt • protector (caliper body) caution when installing the brake hoses to the cali- per and master cylinder , lightly touch the brake pipe with the projections on them. S s warning...

  • Page 122

    Chas assembling and installing the front and rear brake caliper 4-34 9. Bleed: • brake system refer to “air bleeding” section. 10. Check: • brake fluid level below the minimum level mark add the recommended brake fluid to the proper level. Refer to “brake fluid inspection” in chapter 3. ”lower” leve...

  • Page 123

    Chas bleeding the hydraulic brake system 4-35 eas00134 bleeding the hydraulic brake system s s warning bleed the hydraulic brake system whene- ver: • the system is disassembled. • a brake hose is loosened, disconnected or replaced. • the brake fluid level is very low. • brake operation is faulty. No...

  • Page 124

    Chas bleeding the hydraulic brake system 4-36 note: loosening the bleed screw will release the pressure and cause the brake lever to contact the throttle grip or the brake pedal to fully extend. H. Tighten the bleed screw and then release the brake lever or brake pedal. I. Repeat steps (e) to (h) un...

  • Page 125

    Chas front forks 4-37 front forks cap bolt o-ring spacer spring seat fork spring inner fork tube damper rod oil lock pieces circlip 10 dust seal 11 oil seal 12 washer 13 slide bush 14 outer fork tube 15 axle holder 16 fork boot c use new one 23 nm (2,3m•kg, 17ft•lb) 30 nm (3,0 m • kg, 22ft•lb) a for...

  • Page 126

    Chas removal/disassembly 4-38 removal s s warning support the motorcycle securely so there is no danger of it falling over. 1 elevate the front wheel by placing a suitable stand under the engine. 2. Remove: • brake caliper assembly 3. Loosen: • upper bracket pinch bolt • cap bolt • lower bracket pin...

  • Page 127

    Chas removal/disassembly 4-39 3. Drain: • fork oil 4. Remove: • retaining clip use a thin slotted head screwdriver • washer caution take care not to scratch the inner tube 5. Remove: • bolt (damper rod) • cooper washer note: hold the damper rod to loosen the bolt (damper rod) by the t-handle and the...

  • Page 128

    Chas disassembly/checking the front fork legs 4-40 7. Remove: • inner fork tube a. Hold the front fork leg horizontally. B. Securely clamp the brake caliper bracket in a vise with soft jaws. C. Separate the inner tube from the outer tube by pulling the inner tube forcefully but care- fully. Caution ...

  • Page 129

    Chas checking the front fork legs/assembling the front fork legs 4-41 3. Check: • damper rod • piston ring damage/wear replace. Obstruction blow out all of the oil pas- sages with compressed air. • rebound spring damage replace. 4. Check: • cap bolt o-ring damage/wear replace. Eas00659 assembling th...

  • Page 130

    Chas assembling the front fork legs 4-42 2. Lubricate: • inner tube’s outer surface 3. Tighten: • damper rod assembly bolt note: while holding the damper rod assembly with the damper rod holder and t-handle, tighten the damper rod assembly bolt. 4. Install: • outer tube bushing (with the fork seal d...

  • Page 131

    Chas assembling the front fork legs 4-43 note: • before installing the oil seal, lubricate its lips with lithium-soap-based grease. • lubricate the outer surface of the inner tube with fork oil. • before installing the oil seal, cover the top of the front fork leg with a plastic bag 2 to protect the...

  • Page 132

    Chas assembling the front fork legs 4-44 note: • while filling the front fork leg, keep it upright. • after filling, slowly pump the front fork leg up and down to distribute the fork oil. 9. Install: • spring • spring seat • spacer • cap bolt note: • install the spring with the smaller pitch facing ...

  • Page 133

    Chas steering head and handlebars 4-45 stering head and hadlebars handlebar handlebar grip (right) handlebar grip (left) handlebar holder (upper) handlebar crown ring nut 10 cover 11 bearing race 12 headlight stay a tightening steps •tightening ring nut 35nm to 40nm (3.5 to 4.0 m•kg, 25.6 to 29.3 ft...

  • Page 134

    Chas removal 4-46 removal 1. Elevate the front wheel by placing a suitable stand under the engine. S s warning securely support the motorcycle so there is no danger of falling over 2. Remove: • front wheel refer to the “front wheel removal” section. • front fork refer to the “front fork removal” sec...

  • Page 135

    Chas removal 4-47 0 km/h 4 0 6 0 8 0 1 0 0 1 2 0 1 3 0 2 0 y 0 0 0 0 1 5 0 0 0 8 7. Remove: • flasher lights (left and right) • brake hose guide (from left side only) 8. Disconnect: • speedometer cable 9. Remove: • bands 10. Disconnect: • meter leads • handlebar switch leads • main switch leads • fl...

  • Page 136

    Chas removal 4-48 15. Loosen: • screws (throttle cable housing) 16. Remove: • handlebar holders • handlebars note: for completely removal of the handlebar, be sure to clear the throttle cable housing 17. Remove: • flange nut • handlebar crown 18. Remove: • lock washer • ring nut 1 • ring nut 2 • cov...

  • Page 137

    Chas removal/inspection 4-49 19. Remove: • bearing cover • ball race (top-upper) • ball bearing (22pcs) inspection 1. Wash the bearing in solvent. 2. Inspect: • bearings • bearing races pitting/damage replace • dust seal wear/damage replace bearing race replacement steps: • remove the bearing races ...

  • Page 138

    Chas inspection/installation 4-50 4. Inspect: • handlebar cracks/bend/damage replace s s warning do not attempt to straighten a bent handle- bar as this may dangerously weaken the handlebar. Handlebar replacement steps: • remove the hadlebar grip and handlebar switch (left) and lever holder. • insta...

  • Page 139

    Chas installation 4-51 3. Install: • ball race (upper-lower) • bearing cover • under bracket • ring nut s s warning hold the under bracket until its secured 4. Tighten: • ring nut tightening steps: • tighten the ring nut using the ring nut wrench note: set the torque wrench to the right nut wrench s...

  • Page 140

    Chas installation 4-52 6. Install: • meter assembly 7. Install: • front fork refer to the “front fork installa- tion” section. Note: in this stage, temporarily tighten the pinch bolts (handlebar crown). 8. Tighten: • flange nut (steering stem) • pinch bolts (handlebar crown) note: • install the brak...

  • Page 141

    Chas installation 4-53 9. Install: • handlebar • handlebar holders note: the handlebar should be installed in the posi- tion assigned by the position mark caution first tighten the bolts on the front side of the handlebar holder, and then tighten the bolts on the rear side. Note: before installing t...

  • Page 142

    Chas installation 4-54 12. Install: • headlight lens unit 13. Install: • front wheel refer to the “front wheel installa- tion” section. 14. Adjust: • clutch cable free play refer to the “clutch adjustment” section in chapter 3. Front wheel axle: 80 to 100 nm (8.0 a 10.0 m·kg,58.6 to 73.3ft·lb) axle ...

  • Page 143

    Chas rear shock absorber and swingarm 4-55 rear shock absorber and swingarm rear shock absorber assembly spring bush a spring preload (installed): for dt125re standard length: 230 mm minimum length: 220 mm maximum length: 235 mm 30 to 35 nm (3,0 to 3,5 m • kg, 22 to 25,6 ft•lb) a spring preload (ins...

  • Page 144

    Chas rear shock absorber and swingarm 4-56 swingarm relay arm connecting arm chain case chain guard chain guide collar bearing oil seal 10 bush 11 plain washer 12 shim 13 thrust cover 45 to 70 nm (4,5 to 7 m • kg, 33 to 51,3 ft•lb) 45 to 70 nm (4,5 to 7 m • kg, 33 to 51,3 ft•lb) 80 to 100 nm (8 to 1...

  • Page 145

    Chas handling the rear shock absorber/dispo- sing of a rear shock absorber/removing 4-57 eas00686 handling the rear shock absorber s s warning this rear shock absorber contains highly compressed nitrogen gas. Before handling the rear shock absorber, read and make sure you understand the following in...

  • Page 146

    Chas removing the rear shock absorber assembly 4-58 note: place the motorcycle on a suitable stand so that the rear wheel is elevated. 2. Remove: • bolt (connecting arm swingarm) (from swingarm side) 3. Remove: • bolt (shock absorber lower) s s warning when removing the lower bolt hold the swingarm ...

  • Page 147

    Chas removing the swingarm assembly 4-59 removing the swingarm assembly s s warning securely support the motorcycle so there is no danger of falling it over 1. Elevate the rear wheel by placing a suitable stand under the engine. 2. Remove: • rear shock absorber refer to the “rear shock absorber” sec...

  • Page 148

    Chas removing the swingarm assembly 4-60 7. Check: • swingarm free play inspection steps • check the tightening torque of the pivot shaft (swingarm) securing nut • check the swingarm side play by moving it from side to side. If side play noticeable, check the inner collar, bearing, bushing and thrus...

  • Page 149

    Chas removing the swingarm assembly 4-61 10. Remove: • relay arm 11. Remove: • chain protector 12. Remove: • thrust covers • inner collars (swingarm) • inner collars (connecting arm) • inner collar (relay arm) 1 2 1 4 2 2 1 3.

  • Page 150

    Chas checking the rear shock absorber assembly 4-62 eas00695 checking the rear shock absorber assembly 1. Check: • rear shock absorber rod bends/damage replace the rear shock absorber assembly. • rear shock absorber gas leaks/oil leaks replace the rear shock absorber assembly. • spring damage/wear r...

  • Page 151

    Chas checking the swingarm 4-63 4. Check: • dust covers • spacer • washers • oil seals damage/wear replace. • bearings damage/pitting replace. 5. Check: • connecting arms • relay arm damage/wear replace. 6. Check: • bearings • oil seals damage/pitting replace. 1 3 4 2 2 4 3 1 1 1 2 9 8 2 1 1 2.

  • Page 152

    Chas checking the swingarm/installing the swingarm 4-64 7. Check: • spacers damage/scratches replace. Eas00711 installing the swingarm 1. Lubricate: • bearings • spacers • dust covers • pivot shaft 2. Install: • relay arm • connecting arms note: install the connecting arm front bolt from the right. ...

  • Page 153

    Chas installing the swingarm 4-65 4. Adjust: • drive chain slack refer to “adjusting the drive chain slack” in chapter 3. Drive chain slack dt125re 40~55mm (1,77~2,16in.) dt125x 25~40mm (0,98~1,58 in.).

  • Page 154

    Chas drive chain and sprockets 4-66 drive chain and sprockets drive sprocket chain joint drive chain 32 to 37 nm (3,2 to 3,7 m • kg, 23,5 to 27,1 ft•lb) a drive chain b type 428v2 c no. Of links 134 d drive chain slack dt125re 45~55mm (1,77~2,16in) e drive chain slack dt125x 25~40mm (0,984~1,575in).

  • Page 155

    Chas removing the drive chain 4-67 removing the drive chain 1. Stand the motorcycle on a level surface. S s warning securely support the motorcycle so that there is no danger of it falling over. Note: place the motorcycle on a suitable stand so that the rear wheel is elevated. 2. Remove: • crankcase...

  • Page 156

    Chas removing the drive chain/checking the drive chain 4-68 8. Remove: • chain guide rollers (upper and lower) eas00709 checking the drive chain 1. Measure: • ten-link section a of the drive chain out of specification replace the drive chain. 2. Check: • drive chain stiffness clean and lubricate or ...

  • Page 157

    Chas checking the drive chain 4-69 caution this motorcycle has a drive chain with small rubber o-rings between the drive chain side plates. Never use high-pressure water or air, steam, gasoline, certain sol- vents (e.G., benzine), or a coarse brush to clean the drive chain. High-pressure met- hods c...

  • Page 158

    Chas installing the drive chain 4-70 eas00713 installing the drive chain 1. Lubricate: • drive chain • master link 2. Install: • drive chain • drive sprocket • washer • drive sprocket nut note: while applying the rear brake, tighten the drive sprocket nut. 3. Install: • master link • o-ring • master...

  • Page 159

    Chas installing the drive chain 4-71 caution a drive chain that is too tight will overload the engine and other vital parts, and one that is too loose can skip and damage the swingarm or cause an accident. Therefore, keep the drive chain slack within the speci- fied limits..

  • Page 160: Eng

    Eng.

  • Page 161

    5.

  • Page 162

    Chapter 5 engine engine removal……………………………………………………………………5-1 side covers …………………………………………………………………5-1 coolant ………………………………………………………………………5-1 transmission oil …………………………………………………………5-1 exhaust pipe ………………………………………………………………5-2 carburetor …………………………………………………………………5-2 autolube pump cable and hose ………………...

  • Page 163

    Eng engine removal 5-1 engine overhaul engine removal note: it’s not necessary to remove the engine in order to remove the following components: • cylinder head • cylinder • piston and piston ring • power valve • clutch • primary drive gear • kick axle • shift shaft • magneto rotor • stator • autolu...

  • Page 164

    Eng engine removal 5-2 exhaust pipe 1. Loosen: • bolts (exhaust holder) • screw (muffler joint) 2. Remove: • a.I.S. Hose • bolts (exhaust pipe) • exhaust pipe carburetor 1. Remove: • fuel tank • carburetor refer to the “carburetor removal” section in chapter 6. Autolube pump cable and hose 1. Remove...

  • Page 165

    Eng engine removal 5-3 2 1 clutch cable 1. Loosen: • adjuster (clutch cable) 2. Loosen: • adjuster lock nuts (clutch cable) 3. Disconnect: • clutch cable (from clutch push lever and cable guide ). Y.P.V.S. Cables 1. Remove: • pulley cover (power valve) 2. Remove: • pulley (power valve) removal steps...

  • Page 166

    Eng engine removal 5-4 3. Disconnect: • servomotor unit leads 4. Remove: • servomotor unit • adjuster (y.P.V.S. Cable) • pulley housing radiator hoses 1. Disconnect: • radiator hose (inlet) 2. Disconnect: • radiator hose (outlet) leads 1. Disconnect: • battery lead (negative) 2. Disconnect: • spark ...

  • Page 167

    Eng engine removal 5-5 3. Disconnect: • cdi magneto leads 4. Remove: • bands drive chain 1. Remove: • change pedal • crankcase cover (left) • gasket (crankcase cover) 2. Straighten: • lock washer tab 3. Loosen: • nut (drive sprocket) note: when loosening the nut (drive sprocket) apply the rear brake...

  • Page 168

    Eng engine removal/ engine disassembly 5-6 2. Remove: • bolt (engine mount rear lower) • pivot shaft note: the engine and swingarm are installed using the same pivot shaft. Therefore, take care so that the pivot shaft is pulled, not entirely, out, but for enough to set the engine free. 3. Remove: • ...

  • Page 169

    Eng engine disassembly 5-7 2. Remove: • spark plug • thermo unit s s warning handle the thermo unit with special care. Never subject it to strong or allow it to be dropped. In case of being dropped, it must be replaced. 3. Remove: • cover (thermostatic valve) 4. Remove: • gasket • thermostatic valve...

  • Page 170

    Eng engine disassembly 5-8 eas00253 removing the cylinder and piston 1. Remove: • piston pin clip • piston pin • piston caution do not use a hammer to drive the piston pin out. Note: • before removing the piston pin clip, cover the crankcase opening with a clean rag to prevent the piston pin clip fr...

  • Page 171

    Eng engine disassembly 5-9 1. Remove: • water outlet pipe • o-ring (from water outlet pipe) right side left side 2. Remove: • crankcase cover (right) • dowel pins • gasket (crankcase cover) 3. Remove: • bolts • clutch springs • pressure plate • push rod #1 • friction plates • clutch plates • clutch ...

  • Page 172

    Eng engine disassembly 5-10 note: • before loosening the nut (clutch boss) straighten the lock washer tab. • hold the clutch boss to loosen the nut (clutch boss) by the universal clutch hol- der 4. Straighten: • lock washer tab 5. Loosen: • nut (primary drive gear) • nut (balancer gear) note: hold t...

  • Page 173

    Eng engine disassembly 5-11 8. Remove: • spacer collar • oil seal retainer clutch push lever 1. Unhook: • return spring (push lever) 2. Remove: • push lever (clutch) • return spring • washer shift shaft and stopper lever note: with the engine mounted, the shift shaft can be maintained by removing th...

  • Page 174

    Eng engine disassembly 5-12 rotor note: with the engine mounted, the rotor can be maintained by removing the following parts: • crankcase cover (left). 1. Remove: • nut (rotor) • plain washer note: hold the rotor to loosen the nut (rotor) by the universal rotor holder 2. Remove: • rotor • woodruff k...

  • Page 175

    Eng engine disassembly 5-13 1. Remove: • carburetor joint • reed valve assemby • gasket crankcase right 1. Remove: • crankcase (right) note: • loosen the bolts starting with the highest numbered one. • loosen each bolt 1/4 turn and remove them after all bolts are loosened. Removal steps: • attach th...

  • Page 176

    Eng engine disassembly 5-14 caution • use soft hammer to tap on the case half. • tap only on reinforced portions of case. • don’t tap on gasket mating surface. • work slowly and carefully. • make sure the case halves separate evenly. If one end “hangs up”, take pres- sure off the push screw, realign...

  • Page 177

    Eng engine disassembly 5-15 3. Remove: • balancer weight crankshaft 1. Remove: • crankshaft note: • remove the crankshaft with the crankcase separating tool • fully tighten the tool holding bolts, but make sure the tool body is parallel with the case. If necessary, one screw may be bac- ked out slig...

  • Page 178

    Eng engine disassembly 5-16 1. Remove: • hose guide • power valve holder (right) 2. Remove: • bolt (power valve) note: when loosening the power valve connecting bolt , lock the valve by inserting a wooden pice into the exhaust port. 3. Remove: • power valve (right) • power valve (left) • dowel pins ...

  • Page 179

    Eng engine disassembly/ inspection and repair 5-17 1. Remove:(ref. Oilpump) • circlip • drive gear (autolube pump) • circlip • oil seal • collar • pin • drive shaft (autolube pump) • o-ring • autolube pump eas00227 checking the cylinder head 1. Eliminate: • combustion chamber carbon deposits (with a...

  • Page 180

    Eng inspection and repair 5-18 a. Place a straightedge and a thickness gauge across the cylinder head. B. Measure the warpage. C. If the limit is exceeded, resurface the cylin- der head as follows. D. Place a 400 ~ 600 grit wet sandpaper on the surface plate and resurface the cylinder head using a f...

  • Page 181

    Eng inspection and repair 5-19 standard limit cylinder bore “c” 56.00 ~ 56.02 mm (2.204 ~ 2.205 in) taper “t” — 0.05 mm (0.001968 in) out of — 0.01 mm round “r” (0.00039 in) c = maximum of d 1 ~ d 2 t = maximum of d 1 or d 2 - maximum of d 5 or d 6 r = maximum of d 1 , d 3 or d 5 - minimum of d 2 , ...

  • Page 182

    Eng inspection and repair 5-20 note: before measuring the piston ring side clearan- ce, eliminate any carbon deposits from the piston ring grooves and piston rings. 2. Install: • piston ring (into the cylinder) note: level the piston ring into the cylinder with the piston crown. 3. Measure: • piston...

  • Page 183

    Eng inspection and repair 5-21 piston ring oversize • top and 2nd piston rings the size of the top and 2nd oversize piston rings is stamped on the top of each ring. Oversize 25 mm oversize 50 mm piston pin and bearing 1. Lubricate: • small end bearing • piston pin (lightly) 2. Install: • small end b...

  • Page 184

    Eng inspection and repair 5-22 2. Measure: • friction plate thickness out of specification replace the fric- tion plates as a set. Note: measure the friction plate at four places. Eas00281 checking the clutch plates the following procedure applies to all of the clutch plates. 1. Check: • clutch plat...

  • Page 185

    Eng inspection and repair 5-23 2. Measure: • clutch spring free length out of specification replace the clutch springs as a set. Eas00284 checking the clutch housing 1. Check: • clutch housing dogs damage/pitting/wear deburr the clutch housing dogs or replace the clutch housing. Note: pitting on the...

  • Page 186

    Eng inspection and repair 5-24 eas00288 checking the clutch push rods 1. Check: • o-ring • short clutch push rod • long clutch push rod • ball cracks/damage/wear replace the defective part(s). 2. Measure: • long clutch push rod bending limit out of specification replace the long clutch push rod. Eas...

  • Page 187

    Eng inspection and repair 5-25 eas00421 checking the shift forks the following procedure applies to all of the shift forks. 1. Check: • shift fork cam follower • shift fork pawl bends/damage/scoring/wear replace the shift fork. 2. Check: • shift fork guide bar roll the shift fork guide bar on a flat...

  • Page 188

    Eng inspection and repair 5-26 eas00423 checking the transmission 1. Measure: • main axle runout (with a centering device and dial gauge ) out of specification replace the main axle. 2. Measure: • drive axle runout (with a centering device and dial gauge ) out of specification replace the drive axle...

  • Page 189

    Eng inspection and repair 5-27 eas00328 checking the shift shaft 1. Check: • shift shaft • shift pawls bends/damage/wear replace. 2. Check: • stopper lever roller turns roughly replace bend/damage replace 3. Check: • return spring (shift shaft) • return spring (shift pawls) • return spring (stopper ...

  • Page 190

    Eng inspection and repair 5-28 3. Measure: • crankshaft width out of specification replace the crankshaft. 4. Check: • crankshaft sprocket damage/wear replace the cranks- haft. • bearing cracks/damage/wear replace the crankshaft. Autolube pump wear or an internal malfunction may cause pump output to...

  • Page 191

    Eng inspection and repair 5-29 3. Check: • pump output. Out of specification adjust. 4. Check: • drive gear (autolube pump) • drive shaft (autolube pump) • pivot collar (drive shaft) wear/damage replace. Power valve 1. Eliminate: • score marks and lacquer deposits. • carbon deposits. (from power val...

  • Page 192

    Eng inspection and repair 5-30 eas00399 checking the crankcase 1. Thoroughly wash the crankcase halves in a mild solvent. 2. Thoroughly clean all the gasket surfaces and crankcase mating surfaces. 3. Check: • crankcase cracks/damage replace. • oil delivery passages obstruction blow out with compress...

  • Page 193

    Eng engine assembly and adjustments 5-31 autolube pump 5 nm (0.5 m • kg, 3.6ft•lb) autolube pump end cap hose clip adjusting bolt washer drive shaft collar o-ring 10 screw 11 oil seal 12 autolube pump gear 13 pin 14 circlip.

  • Page 194

    Eng engine assembly and adjustments 5-32 autolube pump 1. Lubricate: • oil seal lips 2. Install: • drive shaft (autolube pump) • circlip • pin • drive gear (autolube pump) • circlip • o-ring • autolube pump s s warning • always use a new circlip • always use a new o-ring lightweight lithium-soap bas...

  • Page 195

    Eng engine assembly and adjustments 5-33 power valve power valve power valve holder (right) o-ring power valve holder (left) gasket seal pulley housing pulley pulley cover y.P.V.S. Cable 7 nm (0.7 m • kg, 5.1ft•lb) 7 nm (0.7 m • kg, 5.1ft•lb) 7 nm (0.7 m • kg, 5.1ft•lb) a use new one a use new one 1...

  • Page 196

    Eng engine assembly and adjustments 5-34 power valve 1. Lubricate: • power valve connecting rod • o-rings • gasket seal • bushes (power valve shaft contact surface) • power valve surface 2. Install: • power valve holder (left) • gasket seal (to left power valve) • dowel pins • power valve (left and ...

  • Page 197

    Eng engine assembly and adjustments 5-35 crankshaft/piston/balancer balancer gear bearing straight key balancer weight bearing drive gear oil seal collar bearing 10 piston ring set 11 piston 12 piston pin 13 piston pin clip 14 small end bearing 15 staight key 16 crank (right) 17 thrust bearing 18 co...

  • Page 198

    Eng engine assembly and adjustments 5-36 transmission main axle 2nd pignion gear 3rd 4th pignion gear 5th pignion gear 6th pignion gear plain washer circlip bearing cylindrical bearing 10 drive axle 11 1st wheel gear 12 2nd wheel gear 13 3rd wheel gear 14 4th wheel gear 15 5th wheel gear 16 6th whee...

  • Page 199

    Eng engine assembly and adjustments 5-37 shifter shift cam stopper lever return spring securing bolt shift fork #1 shift fork #2 shift fork #3 shift fork #1 shift fork #2 14 nm (1.4 m • kg,10ft•lb).

  • Page 200

    Eng engine assembly and adjustments 5-38 eas00408 installing the crankshaft 1. Install: • crankshaft assembly note: • install the crankshaft assembly with the crankshaft installer pot, crankshaft installer bolt, adapter (m12) and spacer. 2. Install: • crankshaft assembly caution to avoid scratching ...

  • Page 201

    Eng engine assembly and adjustments 5-39 note: • the embossed marks mqra.Anq on the shift forks should face towards the left side of the engine and be in the following sequence: “3”, “2”, “1”. • the grooved side of the shift fork guide bar should face towards the right side of the engine. Crankcase ...

  • Page 202

    Eng engine assembly and adjustments 5-40 caution before installing and torquing the bolts (crankcase) be sure to check wheter the transmission is functioning properly by manually rotating the shift cam either way. Note: tighten the bolts (crankcase) in stage, using a crisscross pattern. 5. Apply: • ...

  • Page 203

    Eng engine assembly and adjustments 5-41 magneto rotor stator assembly rotor washer 80 nm (8.0 m • kg, 58ft•lb).

  • Page 204

    Eng engine assembly and adjustments 5-42 magneto rotor 1. Install: • stator 2. Connect: • neutral switch lead 3. Install: • woodruf key • rotor • plain washer • nut (rotor) note: • clean the tapered portions of the cranks- haft and rotor. • when installing the rotor, make sure the key is properly se...

  • Page 205

    Eng engine assembly and adjustments 5-43 shift shaft shift tank spring circlip oil seal change pedal 15 nm (1.5 m • kg, 11ft•lb).

  • Page 206

    Eng engine assembly and adjustments 5-44 stopper lever and shift shaft 1. Install: • return spring • stopper lever note: • mesh the stopper lever with the shift cam. 2. Install: • shift shaft note: • lubricate the oil seal lips with lithium- soap-based grease. 3. Check: • shift pawl position gaps a ...

  • Page 207

    Eng engine assembly and adjustments 5-45 2. Install: • washer • return spring • push lever 3. Set the return spring to the spring hook . 3 1 2 4.

  • Page 208

    Eng engine assembly and adjustments 5-46 clutch and primary drive gear clutch spring pressure plate push plate clutch plate friction plate clutch damper clutch boss thrust washer clutch housing 10 thrust plate 11 conical spring washer 12 push rod #1 13 ball 14 push rod #2 15 push lever axle 16 retur...

  • Page 209

    Eng engine assembly and adjustments 5-47 balancer gear, primary drive gear and clutch 1. Install: • oil seal retainer • spacer collar note: before installing the spacer collar greae the oil seal lip . 2. Install: • straight key • drive gear (balancer weight) • baffle plate 3. Install: • driven gear ...

  • Page 210

    Eng engine assembly and adjustments 5-48 s s warning always use a new lock washer 5. Tighten: • nut (primary drive gear) • nut (balancer driven gear) note: hold the rotor to tighten the nut (primary drive gear) and nut (balancer driven gear) by the universal rotor holder 6. Bend the lock washer tab ...

  • Page 211

    Eng engine assembly and adjustments 5-49 8. Install: • push rod #2 • ball • conical spring washer • thrust plate • clutch housing • thrust washer • clutch boss • lock washer • nut (clutch boss) s s warning always use a new lock washer note: • be careful to install the conical spring was- her in prop...

  • Page 212

    Eng engine assembly and adjustments 5-50 11. Install: • friction plates • clutch plates • clutch damper installation steps • install the friction plate onto the clutch boss. • install the clutch plate so as to locate the projection at #1. • install the friction plate with the larger insi- de diamete...

  • Page 213

    Eng engine assembly and adjustments 5-51 note: tighten the bolts (pressure plate) in stage, using a crisscross pattern 14. Adjust: • clutch mechanism free play refer to the “clutch mechanism adjustment” section in chapter 3. 15. Install: • gasket (crankcase cover) • dowel pins • crankcase cover (rig...

  • Page 214

    Eng engine assembly and adjustments 5-52 cylinder head and cylinder spark plug cylinder head cylinder head gasket cylinder cylinder gasket a spark plug b manufacturer ngk c type: br9es d plug gap: 0.7~0.8mm (0.028~0.0012in) e cylinder head warrage limit: 0.03mm(0.0012in) 13 nm (1.3m • kg, 9.4ft•lb) ...

  • Page 215

    Eng engine assembly and adjustments 5-53 piston, cylinder and cylinder head 1. Install: • bearing • piston • piston pin • piston pin clips note: • apply engineoil tothe piston pin, bearings and piston skirts areas. • make sure the arrow mark on the piston points towards the exhaust side of the cylin...

  • Page 216

    Eng engine assembly and adjustments 5-54 3. Install: • dowel pins • gasket (cylinder) s s warning always use a new gasket 4. Install: • cylinder • clutch cable guide note: install the cylinder with one hand while com- pressing the piston rings with the other hand 5. Tighten: • nuts (cylinder) note: ...

  • Page 217

    Eng engine assembly and adjustments 5-55 8. Install: • o-ring • thermostatic valve • gasket note: apply the lithium soap base grease to the o- ring s s warning • always use a new o-ring. • always use a new gasket. 9. Install: • cover (thermostatic valve) 10. Install: • spark plug • thermo unit s s w...

  • Page 218

    Eng engine assembly and adjustments 5-56 11. Install: • hoses (inlet and outlet ) remounting the engine reverse the “engine removal” procedure. Note the following points: 1. Install: • engine assemb (to right side) • mounting bolts note: • apply lithium soap base grease to the pivot shaft. • tempora...

  • Page 219

    Eng engine assembly and adjustments 5-57 3. Bend the lock washer tab along the nut flats 4. Install: • gasket (crankcase cover) • crankcase cover (left) • change pedal note: tighten the screws (crankcase cover) in stage, using a crisscross pattern. 5. Adjust: • drive chain slack refer to the “drive ...

  • Page 220

    Eng engine assembly and adjustments 5-58 2 1 8. Connect: • servomotor unit lead • cables (y.P.V.S.) (to power valve pulley) 9. Install: • pulley (power valve) 10. Adjust: • y.P.V.S. Cables refer to the “y.P.V.S. Cable adjust- ment” section in chapter 3. Note: before adjusting the y.P.V.S. Cables, tu...

  • Page 221

    Eng engine assembly and adjustments 5-59 13. Air bleeding: • autolube pump refer to the “autolube pump air ble- eding” section in chapter 3. 14. Install: • autolube pump cover 15. Install: • gasket (exhaust pipe) • exhaust pipe s s warning always use a new gasket 16. Fill: • radiator • reservoir tan...

  • Page 222

    Eng engine assembly and adjustments 5-60 17. Fill: • crankcase refer to the “transmission oil repla- cement” section in chapter 3. Total amount: 0,92l.

  • Page 223: Cool

    Cool.

  • Page 224

    6.

  • Page 225

    Chapter 6 cooling system water pump ……………………………………………………………………6-1 removal ………………………………………………………………………6-2 inspection……………………………………………………………………6-4 installation …………………………………………………………………6-4 thermostatic valve and radiator ……………………………………6-7 removal ………………………………………………………………………6-8 inspection …………………………………...

  • Page 226: Cooling System

    Cool water pump 6-1 cooling system water pump impeller shaft oil seal pin impeller shaft gear plain washer circlip water pump housing cover gasket dowel pin 10 drain bolt 11 gasket 8 nm (0.8 m • kg, 5.8 ft•lb) a use new one a use new one.

  • Page 227

    Cool water pump 6-2 removal note: it is necessay to disassemble the water pump unless there is no abnormality such as exces- sive change in coolant temperature and/or dis- coloration of coolant or milky transmission oil. 1. Drain: • transmission oil refer to the “transmission oil repla- cement” sect...

  • Page 228

    Cool water pump 6-3 7. Remove: • return spring • bolt (master cylinder) • brake pedal • crankcase cover 8. Remove: • water outlet pipe • housing cover (water pump) • gasket • dowel pins 9. Remove: • circlip • plain washer • impeller shaft gear 10. Remove: • pin • plain washer 11. Remove: • impeller ...

  • Page 229

    Cool water pump 6-4 eas00472 checking the water pump 1. Check: • o-ring damage/wear replace. • oil seal damage/wear replace the water pump housing assembly. 2. Check: • impeller cracks/damage/wear replace the water pump housing assembly. • bearing rough movement replace the water pump housing assemb...

  • Page 230

    Cool water pump 6-5 3. Install: • housing cover (water pump) • water outlet pipe caution • always use new gaskets • always use a new o-ring 4. Install: • crankcase cover (right) • brake pedal • return spring • drain plug (transmission oil) • drain plug (coolant) note: before installing the brake ped...

  • Page 231

    Cool water pump 6-6 6. Fill: • crankcase refer to the “transmission oil repla- cement” section in chapter 3. 7. Fill: • radiator refer to the “coolant replacement” section. 8. Air bleeding: • autolube pump refer to the “autolube pump air blee- ding” section. 9. Install: • autolube pump cover total a...

  • Page 232

    Cool thermostatic valve and radiator 6-7 thermostatic valve and radiator radiator assembly radiator cap inlet hose coolant breather hose outlet hose gasket hose (carburetor warmer inlet) hose (carburetor warmer inlet) thermostatic valve cover 10 gasket 11 thermostatic valve 12 o-ring 8 nm (0.8 m • k...

  • Page 233

    Cool thermostatic valve and radiator 6-8 removal 1. Remove: • side covers (left and right) • seat • exhaust pipe 2. Remove: • radiator cover • oil tank cover • fuel tank refer to the “carburetor removal” section in chapter 7. 3. Drain: • cooling system refer to the “coolant replacement” section in c...

  • Page 234

    Cool thermostatic valve and radiator 6-9 4. Remove: • radiator cap 5. Disconnect: • breather hose (radiator ) 6. Remove: • inlet hose (radiator) • outlet hose (radiator) 7. Remove: • water outlet pipe • o-ring 8. Remove: • radiator fin 9. Remove: • radiator 2 1 4 2 1 3.

  • Page 235

    Cool thermostatic valve and radiator 6-10 10. Remove: • thermostatic valve cover • gasket • thermostatic valve • o-ring eas00455 checking the radiator 1. Check: • radiator fins obstruction clean. Apply compressed air to the rear of the radiator. Damage repair or replace. Note: straighten any flatten...

  • Page 236

    Cool thermostatic valve and radiator 6-11 a. Install the radiator cap tester and radiator cap tester adapter to the radiator cap. B. Apply the specified pressure for ten seconds and make sure there is no drop in pressure. 4. Inspect: • thermostatic valve valve doesn’t open at 63~67ºc (146~153ºf) rep...

  • Page 237

    Cool thermostatic valve and radiator 6-12 full low 2. Install: • radiator 3. Apply grease to the o-ring 4. Install: • o-ring • water outlet pipe s s warning always use a new o-ring 5. Fill: • radiator • reservoir tank (radiator) refer to the “coolant replacement” section in chapter 3. 6. Inspect: • ...

  • Page 238

    Cool thermostatic valve and radiator 6-13 inspection steps • attach the cooling system tester to the radiator • apply 100kpa (1.0 kg/cm 2 , 14psi) pressure. • measure the indicated pressure with the gauge. Radiator cap tester 90890-01325.

  • Page 239: Carb

    Carb.

  • Page 240

    7.

  • Page 241

    Chapter 7 carburetor carburetor ……………………………………………………………………7-1 removal ………………………………………………………………………7-2 disassembly …………………………………………………………………7-3 inspection……………………………………………………………………7-4 assembly ……………………………………………………………………7-6 installation …………………………………………………………………7-8 adjustment …………………………………………………………………7...

  • Page 242: Carburetion

    Carb carburetion 7-1 carburetion carburetor cap throttle valve spring starter plunger throttle stop screw pilot air screw throttle valve needle set pilot jet needle jet 10 gasket 11 main jet 12 needle valve assembly 13 float 14 drain screw main jet (m.J.) #210 main air jet (m.A.J.) ø 0.8 jet needle ...

  • Page 243

    Carb carburetor 7-2 removal note: the following parts can be cleaned and ins- pected without disassembly • throttle valve • starter plunger • throttle stop screw 1. Remove: • side cover (left and right) • seat • radiator cover 2. Turn the fuel cock to “off” position. 3. Disconnect: • fuel hose (from...

  • Page 244

    Carb carburetor 7-3 6. Disconnect: • hoses • oil delivery hose • cooling hoses 7. Loosen: • screw (carburetor joint) • screw (air box) 8. Remove: • carburetor top • carburetor 9. Remove: • cable holder • throttle valve • return spring disassembly 1. Remove: • hoses 2. Remove: • starter plunger assem...

  • Page 245

    Carb carburetor 7-4 4. Remove: • float pin • float • needle valve 5. Remove: • valve seat • main jet • jet needle holder 6. Remove: • throttle stop screw • pilot air screw inspection 1. Inspect: • carburetor mixing chamber body contamination clean note: use petroleum based solvent for cleaning. Blow...

  • Page 246

    Carb carburetor 7-5 3. Inspect: • valve seat • gasket • needle valve note: always replace the needle valve and valve seat as a set. 4. Inspect: • starter plunger wear/contamination replace 5. Check: • free movement stick replace insert the throttle valve into the carburetor body and check for free m...

  • Page 247

    Carb carburetor 7-6 10. Inspect: • float damage replace 11. Inspect: • main jet • needle jet • pilot jet contamination clean note: blow out the jets with compressed air assembly reverse the “disassembly” procedures. Note the following points. Caution before reassembling, wash all parts with clean ga...

  • Page 248

    Carb carburetor 7-7 measurement and adjustment steps: • hold the carburetor in an upside down position. • measure the distance from the mating sur- face on the float chamber (gasket removed) to the top of the float. Caution the float arm should be resting on the needle valve, but not compressing the...

  • Page 249

    Carb carburetor 7-8 7. Intall: • throttle valve note: align the groove of the throttle valve with the projection of the carburetor body. Installation reverse the “removal” procedures. Note the following points. 1. Install: • carburetor assembly note: align the groove of the carburetor joint with the...

  • Page 250

    Carb carburetor 7-9 adjustment fuel level adjustment 1. Measure: • fuel level out of specification adjust fuel level measurement and adjustment steps: • place the motorcycle on a level surface. • use a garage jack under the engine to ensure that the carburetor is positioned ver- tically. • connect t...

  • Page 251

    Carb reed valve 7-10 reed valve reed valve assembly reed valve stopper plate gasket carburetor joint y.E.I.S. Chamber 10 nm (1.0 m • kg, 7.2 ft•lb) b use new one 1 nm (0.1 m • kg, 0.7 ft•lb).

  • Page 252

    Carb reed valve 7-11 removal 1. Remove: • carburetor refer to the “carburetor removal” section. 2. Remove: • carburetor joint 3. Remove: • reed valve assembly • gasket disassembly 1. Remove: • y.E.I.S. Chamber 2. Remove: • reed valve stopper • reed valve 1 2 1 2 1 1.

  • Page 253

    Carb reed valve 7-12 inspection 1. Inspect: • reed valve • reed valve stopper cracks/damage replace 2. Measure: • reed valve bending limit out of specification replace. Surface plate 3. Measure: • reed valve stopper height out of specification replace. Surface plate 4. Inspect: • carburetor joint • ...

  • Page 254

    Carb reed valve 7-13 • fit the reed valve stopper out with the corresponding cut on the reed valve. 2. Tighten: • screws (reed valve) note: tighten each screw gradually to avoid war- ping. 3. Install: • y.E.I.S. Chamber note: the arrow on the y.E.I.S. Chamber must point forward. Installation reverse...

  • Page 255: Elec

    Elec.

  • Page 256

    8.

  • Page 257

    Chapter 8 electrical system dt125re circuit diagram …………………………………………………8-1 color code …………………………………………………………………8-1 electrical components …………………………………………………8-2 checking switch continuity …………………………………………8-4 checking the switches …………………………………………………8-5 ignition system ………………………………………………………………8-6 circ...

  • Page 258: Electrical

    Elec dt125re circuit diagram 8-1 electrical dt125re circuit diagram b black r red o orange l blue p pink y yellow g green w white ch chocolate dg dark green sb sky blue br brown l/y blue/yellow b/y black/yellow b/w black/white b/r black/red w/r white/red w/l white/blue y/r yellow/red g/r green/red g...

  • Page 259

    Elec electrical components 8-2 electrical components(1) cdi unit servomotor battery fuse neutral switch thermo unit rectifier/regulator ignition coil main switch ignition coil: primary coil resistance: 0.23 Ω at 20 °c secondary coil resistance: 7.9 k Ω at 20 °c.

  • Page 260

    Elec electrical components 8-3 electrical components(2) flasher relay conductor wire rectifier 2 oil gauge sidestand switch brake switch relay horn battery: capacity: 12v 6ah no maintenance.

  • Page 261

    Elec checking switch continuty 8-4 lock open off check on gy br r b a b b w / eas00730 checking switch continuity check each switch for continuity with the poc- ket tester. If the continuity reading is incorrect, check the wiring connections and if necessary, replace the switch. Caution: never inser...

  • Page 262

    Elec checking the switches 8-5 eas00731 checking the switches check each switch for damage or wear, proper connections, and also for continuity between the terminals. Refer to “checking switch con- tinuity”. Damage/wear repair or replace. Improperly connected properly connect. Incorrect continuity r...

  • Page 263: Ignition System

    Elec ignition system 8-6 ignition system the circuit diagram showns the ignition system..

  • Page 264

    Elec ignition system 8-7 note: for the color codes see the electric diagram magneto cdi battery fuse starter relay starting engine main switch c.D.I. Ignition coil 7 5 · 8 · 9 4 2 6 1.

  • Page 265

    Elec ignition system 8-8 eas00736 troubleshooting check: 1. Main and ignition fuses 2. Battery 3. Spark plug 4. Ignition spark gap 5. Spark plug cap resistance 6. Ignition coil resistance 7. Main switch 8. Engine stop switch 9. Neutral switch 10. Sidestand switch 11. Pickup coil resistance 12. Wirin...

  • Page 266

    Elec ignition system 8-9 • connect the pocket tester ( Ω x 1k) to the ignition coil as shown. Negative tester probe ignition coil base positive tester probe spark plug lead • measure the secondary coil resistance. Secondary coil resistance 7.9 +/- k Ω 20°c (68 °c) • is the ignition coil ok? Eas00744...

  • Page 267

    Elec ignition system 8-10 eas00749 5. Main switch • disconnect the main switch coupler and lead from the wireharness (red). • connect the pocket tester ( Ω 100) to the main switch. Positive tester probe red lead negative tester probe brown-blue terminal • turn the main switch to “on” and “off”. • ch...

  • Page 268

    Elec ignition system 8-11 7. Source coil resistance • disconnect the cdi magneto coupler from the wireharness. • connect the pocket tester ( Ω 100) to the source coil. Positive tester probe green/white terminal negative tester probe black/red teminal • measure the source coil resistance. Source coil...

  • Page 269

    Elec ignition system 8-12 eas00752 procedure (2) 1. Sidestand switch • disconnect the sidestand switch leads from the wireharness. • connect the pocket tester ( Ω 100) to the sidestand switch. Positive tester probe blue/white terminal negative tester probe blue/black terminal • move the sidestand to...

  • Page 271: Charging System

    Elec charging system 8-14 eas00773 charging system circuit diagram generator rectifier/regulator battery main fuse.

  • Page 272

    Elec charging system 8-15 eas00774 troubleshooting 1. Main fuse 2. Battery 3. Charging voltage 4. Charging coil resistance 5. Wiring connections (of the entire charging system) note: • before troubleshooting, remove the follo- wing part(s): 1. Side covers (left and right) 2. Seat 3. Fuel tank 4. Rad...

  • Page 273: Lighting System

    Elec lighting system 8-16 eas00780 lighting system circuit diagram magento-cdi rectifier/regulator main switch 21 “lights” switch 29 headlight 34 tail light 36 meter lights.

  • Page 274

    Elec lighting system 8-17 eas00781 troubleshooting check: 1. Headlight bulb/”hi beam” indicator light bulb 2. Headlight bulb socket/”hi beam” 3. “lights” (dimmer) switch 4. “lights” switch 5. Lighting voltage 6. Lighting coil resistance 7. Wiring connection (of the entire lighting system) note: • be...

  • Page 275

    Elec lighting system 8-18 2. Bulb socket • disconnect the bulb socket leads from the wire harness. • install the bulb to the bulb socket. • connect the pocket tester ( Ω 100) to the bulbs terminals. Positive tester probe yellow lead negative tester probe black lead positive tester probe green lead n...

  • Page 276

    Elec lighting system 8-19 4. Lighting voltage. • turn (dimmer) switch to “lo”. • connect the pocket tester (dc 20 v) to the battery. Positive tester probe green terminal negative tester probe black terminal • connect the inductive tachometer to the spark plug lead. • start the engine and check the l...

  • Page 277

    Elec lighting system 8-20 troubleshooting check: 1. Meter light bulb 2. Meter light bulb socket 3. Wiring connection (of the entire lighting system) note: • before troubleshooting, remove the follo- wing part(s): 1. Sidecovers (left and right) 2. Seat 3. Fuel tank 4. Headlight cover 5. Headlight uni...

  • Page 278

    Elec lighting system 8-21 2. Bulb socket • disconnect the bulb socket lead and cou- pler from the wire harness. • install the bulb to the bulb socket. • connect the pocket tester ( Ω 1) to the bulbs socket lead end and coupler. Positive tester probe blue lead negative tester probe black terminal • c...

  • Page 279

    Elec lighting system 8-22 troubleshooting check: 1. Tail/brake light bulb/auxiliary light bulb 2. Tail light bulb socket/auxiliary light 3. Main switch 4. Wiring connection (of the entire lighting system) note: • before troubleshooting, remove the follo- wing part(s): 1. Sidecovers (left and right) ...

  • Page 280

    Elec lighting system 8-23 2. Bulb socket • disconnect the bulb socket and leads from the wire harness. • install the bulb to the bulb socket. • connect the pocket tester ( Ω 1) to the bulbs socket lead end and coupler. A positive tester probe blue terminal negative tester probe black terminal b posi...

  • Page 281

    Elec lighting system 8-24 eas00787 4. Wiring • check the entire lighting system’s wiring. Refer to “circuit diagram”. • is the lighting system’s wiring properly con- nected and without defects? Properly connect or repair the lighting system’s wiring. Check the condition of each of the ligh- ting sys...

  • Page 283: Signaling System

    Elec signal system 8-26 eas00793 signaling system circuit diagram main switch main fuse battery 15 neutral switch 35 engine oil level switch 37 diode 20 horn switch 25 horn 22 turn switch 26 turn signal relay 34 tail/brake light 28 rear brake light switch 27 front brake light switch.

  • Page 284

    Elec signal system 8-27 eas00794 troubleshooting check: 1. Fuse 2. Battery 3. Main switch 4. Wiring connections (of the entire signaling system) note: • before troubleshooting, remove the follo- wing part(s): 1. Side covers (left and right) 2. Seat 3. Fuel tank 4. Headlight cover 5. Headlight unit •...

  • Page 285

    Elec signal system 8-28 1. Bulb • remove the bulb. • connect the pocket tester ( Ω 1) to the bulb terminals. Positive tester probe terminal negative tester probe terminal • check the bulb for continuity. Flasher light does not brink 2. Bulb socket • install the bulb to the sockets. • disconnect the ...

  • Page 286

    Elec signal system 8-29 3. “turn” switch • disconnect the “turn” switch (left hand- lebar switch) coupler from the wire har- ness. • connect the pocket tester ( Ω 1) to the “turn” switch. When turning “turn”” switch to “r”: positive tester probe brown/white lead negative tester probe dark green lead...

  • Page 287

    Elec signal system 8-30 1. Bulb • remove the bulb. • connect the pocket tester ( Ω 1) to the bulb terminals. Positive tester probe terminal negative tester probe terminal • check the bulb for continuity. • is the bulb ok? Brake ligh does not come on 2. Bulb socket • disconnect the bulb socket couple...

  • Page 288

    Elec signal system 8-31 3. Front brake switch • disconnect the front brake switch coupler from the wire harness. • connect the pocket tester ( Ω 1) to the brake switch coupler. Positive tester probe brown terminal negative tester probe green/yellow terminal • check the brake switch for continuity. S...

  • Page 289

    Elec signal system 8-32 1. Bulb • remove the bulb. Refer to the “meter assembly” section. • connect the pocket tester ( Ω 1) to the bulb terminals. Positive tester probe terminal negative tester probe terminal • check the bulb for continuity. • is the bulb ok? “neutral” indicator light does not come...

  • Page 290

    Elec signal system 8-33 3. Neutral switch • disconnect the cdi magneto coupler from the wire harness. • connect the pocket tester ( Ω 1) to the neu- tral switch coupler. Positive tester probe sky blue terminal negative tester probe frame ground • shift the transmission in neutral and gear. • check t...

  • Page 291

    Elec signal system 8-34 1. Bulb • remove the bulb. Refer to the “meter assembly” section. • connect the pocket tester ( Ω 1) to the bulb terminals. Positive tester probe terminal negative tester probe terminal • check the bulb for continuity. • is the bulb ok? “oil” indicator light does not come on ...

  • Page 292

    Elec signal system 8-35 3. Oil level switch (diode) • disconnect the oil level switch from the wire harness. • connect the pocket tester ( Ω 1) to the neu- tral switch coupler. Positive tester probe black/red terminal negative tester probe sky blue terminal • check the oil level switch for continuit...

  • Page 293

    Elec signal system 8-36 1. “horn” switch • disconnect the “horn” switch (left hand- lebar switch) couplers from the wire har- ness. • connect the pocket tester ( Ω 1) to the “horn” switch. Positive tester probe pink terminal negative tester probe black terminal • check the “horn” switch for continui...

  • Page 294

    Elec signal system 8-37 4. Horn • disconnect the “pink” lead at the horn ter- minal. • connect a jumper lead to the horn ter- minal and ground the jumper lead. • does the horn sounds ok? 5. Voltage • connect the pocket tester (dc20v) to the horn at the pink terminal. Positive tester probe pink termi...

  • Page 295: Cooling System

    Elec cooling system 8-38 eas00807 cooling system circuit diagram battery main switch main fuse 13 thermo switch.

  • Page 296

    Elec cooling system 8-39 eas00808 troubleshooting check: 1. Main fuse 2. Battery 3. Main switch 4. Thermo switch 5. Wiring connections (the entire cooling system) note: • before troubleshooting, remove the follo- wing part(s): 1. Side covers (left and right) 2. Seat 3. Fuel tank 4. Headlight cover 5...

  • Page 297

    Elec cooling system 8-40 3. Main switch • disconnect the main switch coupler from the wire harness. • connect the pocket tester ( Ω 1) to the main switch. Positive tester probe red lead negative tester probe brown-blue terminal • turn the main switch to “on”, “off” and “park”. • check the main switc...

  • Page 298

    Elec cooling system 8-41 eas00795 5. Wiring • check the entire signal system’s wiring. Refer to “circuit diagram”. • is the signaling system’s wiring properly connected and without defects? Properly connect or repair the signaling system’s wiring. Check the condition of each of the sig- naling syste...

  • Page 299: Yamaha Power Valve System

    Elec yamaha power valve system 8-42 yamaha power valve system circuit diagram 16 cdi unit main switch main fuse battery 18 servomotor.

  • Page 300

    Elec motor 8-43 troubleshooting check: 1. Fuse 2. Battery 3. Main switch 4. Servomotor operation 5. Wiring connections (yamaha power valve system) 6. Servomotor and tachometer operation note: • before troubleshooting, remove the follo- wing part(s): 1. Side covers (left and right) 2. Seat 3. Fuel ta...

  • Page 301

    Elec motor 8-44 3. Main switch • disconnect the main switch coupler from the wire harness. • connect the pocket tester ( Ω 1) to the main switch. Positive tester probe red lead negative tester probe brown-blue terminal • turn the main switch to “on”, “off” and “park”. • check the main switch for con...

  • Page 302

    Elec motor 8-45 6. Servomotor and tachometer operation • start the engine and increase revolution to about 7000rev/min. • check servomotor and tachometer for operation. Pocket tester 90890-03112 • is the servomotor ok? Replace the servo- motor. Yes no.

  • Page 303: Meter Assembly

    Elec meter assembly 8-46 meter assembly speedometer bulb bulb socket speedometer cable meter cushion meter bracket stopper clip washer damper collar.

  • Page 304

    Elec meter assembly 8-47 removal 1. Remove: • headlight cover 2. Disconnect: • headlight leads • auxiliary light leads 3. Remove: • band 4. Disconnect: • speedometer cable 5. Disconnect: • meter leads 6. Remove: • meter assembly 1 1.

  • Page 305

    Elec meter assembly 8-48 7. Remove: • meter cushion • meter lights • leads caution do not remove the indicator bulbs sockets by pulling the leads installation reverse the “removal” procedure. Note the following points: 1. Install the meter lights, indicator lights and leads as shown. ”oil” indicator...

  • Page 306

    Elec meter assembly 8-49 note: install the headlight lens unit onto the head- light stay by fitting the guide rubber pro- perly in the guide hole of the headlight unit. 3. Install: • headlight cover 4. Adjust: • headlight beam refer to the “headlight beam adjust- ment” section. 1.

  • Page 307: Trbl

    Trbl shtg ?.

  • Page 308

    9 ?.

  • Page 309

    Chapter 9 troubleshooting starting failure / hard starting ……………………………………9-1 fuel system …………………………………………………………………9-1 electrical system ………………………………………………………9-2 poor idle speed performance ………………………………………9-3 poor idle speed performance ………………………………………9-3 poor medium and high speed performance ………………...

  • Page 310: Troubleshooting

    Troubleshooting note: the following troubleshooting does not cover all the possible causes of trouble. It should be help- ful, however, as a guide to troubleshooting. Refeer to the relative procedure in this manual for ins- pection, adjustment and replacement of parts. Starting failure/hard starting...

  • Page 311

    Electrical system probable cause • spark plug • improper plug gap • worn electrodes • wire between terminals broken • improper heat range • faulty spark plug cap • ignition coil • broken or shorted primary/secondary • faulty spark plug lead • broken body • c.D.I. Unit system • faulty c.D.I. Unit • f...

  • Page 312

    Poor idle speed performance poor idle speed performance probable cause • carburetor • improperly returned starter plunger • clogged or loose pilot jet • clogged pilot air passage • improperly adjusted idle speed (throttle stop screw) • improper throttle cable play • faulty pick up coil poor medium a...

  • Page 313

    Compression system probable cause • cylinder and cylinder head • loose spark plug • broken cylinder head gasket • broken cylinder gasket • loose cylinder head or cylinder • worn, damaged or seized cylinder • piston and piston ring • improperly installed piston ring • worn, fatigued or broken piston ...

  • Page 314

    Faulty gear shifting hard shifting probable cause • clutch • improperly adjusted clutch cable • improperly adjusted push lever position • improper engagement of push lever and push rod • warped clutch plate • swollen friction plate • broken clutch plate • transmission oil • high oil level • improper...

  • Page 315

    Clutch dragging probable cause • clutch • improperly adjusted clutch cable • improperly adjusted push lever position • improper engagement of push lever and push rod • warped clutch plate • swollen friction plate • broken clutch boss • transmission oil • high oil level • improper quality (high visco...

  • Page 316

    Instable handling instable handling probable cause • handlebars • improperly installed or bent • steering • improperly installed handle crown • bent steering shaft • improperly installed steering shaft (improperly tightened ringnut) • damaged ball bearing (roller bearing or bearing race) • front for...

  • Page 317

    Faulty signal and lighting system headlight dark probable cause • improper bulb • too many electric accesories • hard charging (broken charging coil and/or faulty rectifier/regualtor) • incorrect connection • improperly grounded • poor contacts (main or “lights” switch) • bulb life expired bulb burn...

  • Page 318

    Faulty y.P.V.S. Probable cause • power valve • seized or damaged power valve • carbon build-up • control cable • improperly adjusted cable • seized or discontinuous cable • electrical parts • insufficient battery capacity (improperly charged battery) • faulty main switch • faulty servomotor • faulty...

  • Page 319

    Dt125 wiring diagram.

  • Page 320

    Components 1. Cdi. Mag. 2. Rect./regu. 3. Battery 4. Fuse 5. Starter relay 6. Starting motor 7. Main sw. 8. Handle sw. R 9. Starter sw. 10. E/g stop sw. 11. Clutch sw. 12. Side stand sw. 13. Thermo sw. 14. Side stand relay 15. Neutral sw. 16. Cdi. Unit 17. Ign. Coil 18. Servo. Motor 19. Lightning re...