Yamaha YZ125X 2023, Owner'S Manual

Page 1: ...this manual carefully before operating this vehicle Il convient de lire attentivement ce manuel avant la premi re utilisation du v hicule YZ125XP PRINTED IN JAPAN 2022 06 0 1 1 E F YZ125X 2023 YZ125X...

Page 2: ...is manual should stay with this vehicle if it is sold Q Il convient de lire attentivement ce manuel avant la premi re utilisation du v hicule Le manuel doit tre remis avec le v hicule en cas de vente...

Page 3: ...Read this manual carefully before operating this vehicle 2023 OWNER S MANUAL YZ125X YZ125XP BRX 28199 70 E0...

Page 4: ...ceives similar complaints it may open an investigation and if it finds that a safety defect exists in a group of vehicles it may order a recall and remedy campaign However Transport Canada cannot beco...

Page 5: ...OWNER S MANUAL 2023 by Yamaha Motor Co Ltd First edition May 2022 All rights reserved Any reprinting or unauthorized use without the written permission of Yamaha Motor Co Ltd is expressly prohibited...

Page 6: ...uested not to undertake inspection adjustment disassem bly or reassembly only by reference to this manual It may lead to servicing trouble and mechanical damage WARNING EWA20270 PLEASE READ THIS MANUA...

Page 7: ...GENERAL INFORMATION 1 SPECIFICATIONS 2 PERIODIC CHECKS AND ADJUSTMENTS 3 CHASSIS 4 ENGINE 5 ELECTRICAL SYSTEM 6 TROUBLESHOOTING 7 TUNING 8 EAM10003 TABLE OF CONTENTS...

Page 8: ......

Page 9: ...REMOVAL AND DISASSEMBLY 1 10 REPLACEMENT PARTS 1 10 INSTRUMENT AND CONTROL FUNCTIONS 1 11 ENGINE STOP SWITCH 1 11 SHIFT PEDAL 1 11 KICKSTARTER LEVER 1 11 FRONT BRAKE LEVER 1 11 REAR BRAKE PEDAL 1 11 F...

Page 10: ...e riding 2 This motorcycle is designed to carry the oper ator only No passengers 3 The failure of motorists to detect and recog nize motorcycles in traffic is the predominat ing cause of automobile mo...

Page 11: ...Many companies with no connection to Yamaha manufacture parts and accessories or offer oth er modifications for Yamaha vehicles Yamaha is not in a position to test the products that these aftermarket...

Page 12: ...e fuel cock if equipped is in the OFF position and that there are no fuel leaks 3 Point the front wheel straight ahead on the trailer or in the truck bed and choke it in a rail to prevent movement 4 S...

Page 13: ...LOCATION OF IMPORTANT LABELS 1 4 EAM20085 LOCATION OF IMPORTANT LABELS Please read the following important labels carefully before operating this vehicle CAN 1 2 3 4 5 6 7 8 9 10 11...

Page 14: ...LOCATION OF IMPORTANT LABELS 1 5...

Page 15: ...LOCATION OF IMPORTANT LABELS 1 6 AUS NZL...

Page 16: ...or the vehicle you have purchased 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 1 Clutch lever 2 Engine stop switch 3 Front brake lever 4 Throttle grip 5 Radiator cap 6 Fuel tank cap 7 Kickstarter l...

Page 17: ...r positive identi fication of the model you own 2 If your vehicle is stolen the authorities will need the number to search for and identify your vehicle EAM30002 VEHICLE IDENTIFICATION NUMBER The vehi...

Page 18: ...wing out and is installed to the fuel tank breather hose NOTICE ECA27110 In this installation make sure the arrow fac es the fuel tank and also downward EAM30615 COLLAR tool for YPVS This collar 1 is...

Page 19: ...t to re ceive an injury or a burn on the engine the exhaust pipe the silencer or the like 6 If coolant is left adhered to the chassis paint and plating will be damaged Therefore rinse it out with wate...

Page 20: ...s a primary kickstarter lever so the engine can be started in any gear if the clutch is disengaged In normal practices however shift to neutral be fore starting EAM30188 FRONT BRAKE LEVER The front br...

Page 21: ...ble EAM30444 STARTER KNOB CHOKE When cold the engine requires a richer air fuel mixture for starting A separate starter circuit which is controlled by the starter knob 1 sup plies this mixture Pull th...

Page 22: ...ush the engine stop switch TIP Continue pushing the engine stop switch till the engine comes to a full stop EAM30197 STARTING A WARM ENGINE Do not operate the starter knob CHOKE Open the throttle slig...

Page 23: ...owing parts are replaced a break in is required Cylinder and Crankshaft A break in is re quired for about an hour Piston Piston ring Valve Camshaft and Gear A break in is required for about 30 minutes...

Page 24: ...nuts Check for looseness in mounted areas of parts as well as engine mounting bolts and engine brackets 2 For the chassis Check welds and mounted areas of the frame the swingarm the link the bracket a...

Page 25: ...hock absorber Link to swingarm Mounting of rear shock absorber Rear shock absorber and frame Mounting of swingarm Tightening of pivot shaft Wheel s Mounting of wheel Front Tightening of wheel axle Tig...

Page 26: ...ES on page 2 6 Plastic cover Tightening of front fender Tightening of fork leg protector Tightening of air scoop Left cover to rear frame Tightening of side cover Tightening of rear fender Tightening...

Page 27: ...ted Also thorough ly rinse the area off with water immediately dry it and then apply a corrosion protec tion spray Improper cleaning can damage plastic parts such as cowlings panels wind shields headl...

Page 28: ...nd nickel plated sur faces 5 Use spray oil as a universal cleaner to re move any remaining dirt 6 Touch up minor paint damage caused by stones etc 7 Wax all painted surfaces 8 Let the motorcycle dry c...

Page 29: ...th the engine stop switch pushed in kick the engine over several times to coat the cylinder walls with oil 4 Lubricate all control cables and the pivoting points of all levers and pedals as well as of...

Page 30: ...MOTORCYCLE CARE AND STORAGE 1 21...

Page 31: ...PECIFICATIONS GENERAL SPECIFICATIONS 2 1 ENGINE SPECIFICATIONS 2 2 CHASSIS SPECIFICATIONS 2 4 TIGHTENING TORQUES 2 6 GENERAL TIGHTENING TORQUE SPECIFICATIONS 2 6 ENGINE TIGHTENING TORQUES 2 7 CHASSIS...

Page 32: ...NS Model Model BRX2 CAN BRX3 AUS NZL Dimensions Overall length 2155 mm 84 8 in Overall width 825 mm 32 5 in Overall height 1290 mm 50 8 in Seat height 970 mm 38 2 in Wheelbase 1455 mm 57 3 in Ground c...

Page 33: ...Quantity disassembled 0 76 L 0 80 US qt 0 67 Imp qt Quantity 0 70 L 0 74 US qt 0 62 Imp qt Cooling system Coolant quantity Radiator including all routes 0 90 L 0 95 US qt 0 79 Imp qt Spark plug s Man...

Page 34: ...ality foam air filter oil Carburetor Type quantity PWK38S 1 ID mark BRX1 00 AUS NZL BRX2 10 CAN Main jet 160 CAN 162 AUS NZL Main air jet 200 Jet needle NYCF 2 CAN NYEE 2 AUS NZL Needle jet 2 9 6 Cuta...

Page 35: ...limit 1 0 mm 0 04 in Specified brake fluid DOT 4 Rear brake Type Hydraulic single disc brake Brake pad lining thickness limit 1 0 mm 0 04 in Specified brake fluid DOT 4 Front suspension Type Telescopi...

Page 36: ...chanical adjustable type Unit for adjustment Click Adjustment value from the start position Soft 20 Adjustment value from the start position STD 10 Adjustment value from the start position Hard 0 Comp...

Page 37: ...o avoid warpage tight en multi fastener assemblies in a crisscross pat tern and progressive stages until the specified tightening torque is reached Unless otherwise specified tightening torque specifi...

Page 38: ...7 4 lb ft Coolant drain bolt M6 1 10 N m 1 0 kgf m 7 4 lb ft Radiator bolt M6 6 10 N m 1 0 kgf m 7 4 lb ft Radiator guard bolt M6 2 10 N m 1 0 kgf m 7 4 lb ft Radiator hose clamp M6 8 1 5 N m 0 15 kg...

Page 39: ...lb ft Segment bolt M8 1 30 N m 3 0 kgf m 22 lb ft Exhaust pipe bolt M6 2 12 N m 1 2 kgf m 8 9 lb ft Exhaust pipe stay bolt front M6 1 12 N m 1 2 kgf m 8 9 lb ft Exhaust pipe stay bolt rear M6 1 12 N m...

Page 40: ...t brake hose union bolt M10 1 30 N m 3 0 kgf m 22 lb ft Front brake caliper bolt M8 2 28 N m 2 8 kgf m 21 lb ft Grip cap bolt M6 2 3 8 N m 0 38 kgf m 2 8 lb ft Engine stop switch screw M3 1 0 5 N m 0...

Page 41: ...t lower M8 2 29 N m 2 9 kgf m 21 lb ft Brake hose holder screw M5 4 3 5 N m 0 35 kgf m 2 6 lb ft Swingarm and patch screw M4 4 2 0 N m 0 20 kgf m 1 5 lb ft Drive chain tensioner bolt M8 1 16 N m 1 6 k...

Page 42: ...ring nut one turn 2 Retighten the steering ring nut 7 N m 0 7 kgf m 5 2 lb ft Side cover bolt front side M6 2 7 N m 0 7 kgf m 5 2 lb ft Side cover bolt rear side M6 2 9 N m 0 9 kgf m 6 6 lb ft Seat b...

Page 43: ...NG THE COOLANT 3 11 CHASSIS 3 13 ADJUSTING THE FRONT DISC BRAKE 3 13 ADJUSTING THE REAR DISC BRAKE 3 13 CHECKING THE BRAKE FLUID LEVEL 3 14 CHECKING THE FRONT BRAKE PADS 3 14 CHECKING THE REAR BRAKE P...

Page 44: ...LUBRICATING THE BRAKE LEVER 3 24 LUBRICATING THE CLUTCH LEVER 3 24 LUBRICATING THE PEDAL 3 24 CHECKING THE SIDESTAND 3 24 LUBRICATING THE SIDESTAND 3 24...

Page 45: ...ce about 7 5 hours Every fifth race about 12 5 hours As required 1 Piston Check piston for carbon deposits and cracks or damage Clean Replace 2 Piston rings Check piston ring end gap and rings for dam...

Page 46: ...17 Cooling system Check coolant level and for leak age Check hoses for cracks or dam age Check radiator cap spring opera tion Change coolant Every 2 years 18 Chassis fasteners Check all chassis fittin...

Page 47: ...earing assemblies for looseness Lubricate with molybdenum disul fide grease 28 Sidestand Lubricate with lithium soap based grease 29 Steering head Check operation free play and tighten if necessary Cl...

Page 48: ...rear brake 3 13 3 13 3 14 3 14 3 14 3 14 3 15 3 15 Drive chain Check drive chain slack and alignment Check that the drive chain is lubricated properly 3 16 4 31 4 31 Wheels Check for excessive wear a...

Page 49: ...screw 1 until the engine runs at the lowest possible speed b Tighten the locknut EAM30475 CHECKING THE THROTTLE GRIP TIP Prior to adjusting throttle grip free play the en gine idling speed should be...

Page 50: ...level a Remove the oil check bolt 1 b Inspect the oil level TIP Be sure the machine is positioned straight up when inspecting the oil level WARNING EWA21090 Never attempt to remove the oil check bolt...

Page 51: ...IP If the clutch lever free play cannot be obtained on the handlebar side use the adjuster on the clutch cable side Clutch cable side a Slide the clutch cable cover b Loosen the locknut 1 c Turn the a...

Page 52: ...er washing the element with air filter cleaner or kerosene squeeze and dry it completely WARNING EWA19110 Do not use gasoline or organic acid alka line volatile oil for washing NOTICE ECA24280 Do not...

Page 53: ...ter element is prop erly seated in the air filter case The engine should never be operated without the air fil ter element installed otherwise the piston s and or cylinder s may become excessively wor...

Page 54: ...3030 A hot radiator is under pressure Therefore do not remove the radiator cap when the en gine is hot Scalding hot fluid and steam may be blown out which could cause serious in jury When the engine h...

Page 55: ...ING THE COOLANT WARNING EWA13030 A hot radiator is under pressure Therefore do not remove the radiator cap when the en gine is hot Scalding hot fluid and steam may be blown out which could cause serio...

Page 56: ...ct the antifreeze concentra tion of the coolant Use only distilled water However if dis tilled water is not available soft water may be used If coolant comes into contact with painted surfaces immedia...

Page 57: ...TICE ECA13490 After adjusting the brake lever position make sure there is no brake drag 4 Install Brake lever cover EAM30480 ADJUSTING THE REAR DISC BRAKE 1 Adjust Brake pedal position a Loosen the lo...

Page 58: ...brake fluids may result in a harmful chemical reaction leading to poor brake performance When refilling be careful that water does not enter the brake fluid reservoir Water will significantly lower th...

Page 59: ...linder cap Reservoir diaphragm Reservoir float front brake Protector rear brake TIP Be careful not to spill any brake fluid or allow the reservoir to overflow Make sure that there is enough brake flui...

Page 60: ...ground WARNING EWA13120 Securely support the vehicle so that there is no danger of it falling over 2 Shift the transmission into the neutral posi tion 3 Pull the drive chain up above the drive chain g...

Page 61: ...alling over 2 Check Steering head Grasp the bottom of the front fork legs and gently rock the front fork Blinding looseness Adjust the steering head 3 Remove Handlebar Upper bracket 4 Adjust Steering...

Page 62: ...ube Replace the oil seal 3 Hold the vehicle upright and apply the front brake 4 Check Front fork operation Push down hard on the handlebar several times and check if the front fork rebounds smoothly U...

Page 63: ...urn the adjuster forcibly beyond its adjusting range 1 Adjust Compression damping a Turn the adjuster 1 in the direction of a or b to make an adjustment TIP Although the total number of clicks of a da...

Page 64: ...bly Refer to REAR SHOCK ABSORBER AS SEMBLY on page 4 28 3 Check Rear shock absorber assembly smooth ac tion Rear suspension link smooth action Sit astride the seat and shake your body up and down seve...

Page 65: ...pecifications as necessary Compression damping for fast compres sion damping NOTICE ECA24370 Do not turn the adjuster forcibly beyond its adjusting range 1 Adjust Compression damping for fast compress...

Page 66: ...damping force adjusting mechanism and to modify the specifications as necessary EAM30240 CHECKING THE SWINGARM OPERATION 1 Check Swingarm smooth action Swingarm free play Refer to SWINGARM on page 4 2...

Page 67: ...looseness in nipples disap pears Make sure that tightening is done in stages not at a time EAM30245 CHECKING THE WHEELS 1 Check Wheel Damage out of round Replace WARNING EWA13260 Never attempt to mak...

Page 68: ...to metal moving parts of the following parts Clutch lever EAM30250 LUBRICATING THE PEDAL 1 Lubricate the pivoting point and metal to met al moving parts of the pedal EAM30504 CHECKING THE SIDESTAND 1...

Page 69: ...4 9 REMOVING THE HANDLEBAR 4 9 CHECKING THE HANDLEBAR 4 9 INSTALLING THE HANDLEBAR 4 9 FRONT FORK 4 14 REMOVING THE FRONT FORK LEGS 4 14 DISASSEMBLING THE FRONT FORK LEGS 4 14 CHECKING THE FRONT FORK...

Page 70: ...CHECKING THE DRIVE CHAIN 4 30 CHECKING THE DRIVE SPROCKET 4 31 CHECKING THE REAR WHEEL SPROCKET 4 31 INSTALLING THE DRIVE CHAIN 4 31...

Page 71: ...able guide b on the number plate The projection c on the lower bracket is in serted into the number plate Remove the number plate by pulling it off the projection When installing the number plate inse...

Page 72: ...wheel TIP Install the brake disc 1 between the brake pads 2 correctly 2 Install Front wheel axle 1 TIP Apply the lithium soap based grease to the front wheel axle 3 Tighten Front wheel axle nut 1 NOTI...

Page 73: ...oth wear a Replace the rear wheel sprocket and the drive sprocket as a set Bent tooth Replace the rear wheel sprock et and the drive sprocket as a set 2 Replace Rear wheel sprocket a Remove the self l...

Page 74: ...stall Drive chain puller right 1 Washer 2 Rear wheel axle nut 3 TIP Temporarily tighten the rear wheel axle nut at this point 5 Adjust Drive chain slack a Refer to DRIVE CHAIN SLACK on page 3 16 6 Tig...

Page 75: ...cation Replace the brake pads as a set 3 Install Brake pad a Connect the plastic hose 1 to the bleed screw 2 and place a container under the end of the plastic hose b Loosen the bleed screw and push t...

Page 76: ...ECKING THE BRAKE FLUID LEVEL on page 3 14 5 Check Brake lever operation A softy or spongy feeling Bleed the brake system Refer to BLEEDING THE HYDRAULIC BRAKE SYSTEM on page 3 15 Front brake caliper b...

Page 77: ...ification Replace the brake pads as a set 3 Install Brake pad a Connect the plastic hose 1 to the bleed screw 2 and place a container under the end of the plastic hose b Loosen the bleed screw and pus...

Page 78: ...r to CHECKING THE BRAKE FLUID LEVEL on page 3 14 5 Check Brake pedal operation A softy or spongy feeling Bleed the brake system Refer to BLEEDING THE HYDRAULIC BRAKE SYSTEM on page 3 15 Brake pad pin...

Page 79: ...en it EAM30054 INSTALLING THE HANDLEBAR 1 Stand the vehicle upright on a level surface WARNING EWA13120 Securely support the vehicle so that there is no danger of it falling over 2 Install Lower handl...

Page 80: ...t grip 1 Apply the adhesive to the handlebar 2 TIP Before applying the adhesive wipe off grease or oil on the handlebar surface a with a lac quer thinner Install the left grip to the handlebar so that...

Page 81: ...e adhesive on the tube guide 2 TIP Before applying the adhesive wipe off grease or oil on the tube guide surface a with a lac quer thinner Align the mating mark b on the right grip with the slot c in...

Page 82: ...stall Throttle cable cap 1 Throttle cable cap screw 2 15 Adjust Throttle grip free play Refer to CHECKING THE THROTTLE GRIP on page 3 5 16 Install Cap cover 1 17 Install Brake master cylinder 1 Brake...

Page 83: ...18 Install Grip cap bolt 1 WARNING EWA21080 After tightening the bolts check that the throttle grip 2 moves smoothly If it does not retighten the bolts for adjustment Grip cap bolt 3 8 N m 0 38 kgf m...

Page 84: ...e Front fork leg EAM30056 DISASSEMBLING THE FRONT FORK LEGS 1 Drain Fork oil 2 Remove Adjuster 1 from the inner tube TIP While compressing the inner tube 2 set the cap bolt ring wrench 4 between the i...

Page 85: ...sly weaken it 2 Check Outer tube Scratches wear damage Replace 3 Measure Fork spring free length a Out of specification Replace 4 Check Damper assembly 1 Bend damage Replace O ring 2 Wear damage Repla...

Page 86: ...ner tube bushing Slide metal Oil seal Copper washer Before assembling the front fork leg make sure that all of the components are clean 1 Stretch the damper assembly fully 2 Fill Damper assembly NOTIC...

Page 87: ...etting position Unless the damping force adjuster is fully loos ened correct damping characteristic cannot be obtained after installation 7 Install Base valve 1 to the damper assembly 2 TIP First brin...

Page 88: ...age the damper assem bly 12 Allow the overflowing oil to escape at the hole a in the damper assembly TIP The overflow measures about 10 cm 0 34 US oz 0 35 Imp oz 13 Check Damper assembly smooth moveme...

Page 89: ...al 1 TIP Install the piston metal onto the slot on inner tube 16 Install Outer tube 1 to the inner tube 2 17 Install Slide metal 1 Washer 2 to the outer tube TIP Press the slide metal into the outer t...

Page 90: ...rough spots Repeat the steps 14 to 20 22 Measure Distance a Out of specification Turn the locknut to specification 23 Install Upper spring seat 1 Fork spring 2 to the damper assembly 3 TIP Install th...

Page 91: ...the damper assembly 4 TIP While compressing the inner tube 5 set the cap bolt ring wrench 7 between the inner tube and locknut 6 Fully finger tighten the adjuster onto the damp er assembly 27 Measure...

Page 92: ...ten the damper assembly 32 Install Protector guide 1 EAM30059 INSTALLING THE FRONT FORK LEGS 1 Install Front fork 1 TIP Temporarily tighten the lower bracket pinch bolts Do not tighten the upper brack...

Page 93: ...ce TIP Turn in the damping adjuster 1 finger tight and then turn out to the originally set position 7 Adjust Compression damping force TIP Turn in the damping adjuster 1 finger tight and then turn out...

Page 94: ...FRONT FORK 4 24 1...

Page 95: ...lace 3 Replace Bearing Bearing race a Remove the bearing race from the steer ing head pipe 1 with a long rod 2 and a hammer b Remove the bearing race from the lower bracket 3 with a chisel 4 and a ham...

Page 96: ...teering ring nut with its stepped side a facing downward Tighten the steering ring nut with a steering nut wrench 2 Refer to CHECKING AND ADJUSTING THE STEERING HEAD on page 3 17 5 Check the steering...

Page 97: ...steering ring nut little by lit tle 10 Adjust Front fork top end a 11 Tighten Upper bracket pinch bolt 1 Lower bracket pinch bolt 2 WARNING EWA19330 Tighten the lower bracket to specified torque If t...

Page 98: ...1 TIP While removing the rear shock absorber assem bly lower bolt hold the swingarm so that it does not drop down 3 Remove Rear shock absorber assembly upper bolt Rear shock absorber assembly EAM30067...

Page 99: ...ent a Measure the tightening torque of the pivot shaft nut b Check the swingarm side play A by mov ing the swingarm from side to side If the swingarm has side to side play check the bushings the beari...

Page 100: ...ngth b between pin outer sides 2 TIP When measuring a 15 link section of the drive chain make sure that the drive chain is taut Perform this procedure 2 3 times at a different location each time 2 Che...

Page 101: ...HECKING AND REPLACING THE REAR WHEEL SPROCKET on page 4 3 EAM30079 INSTALLING THE DRIVE CHAIN 1 Install Drive chain NOTICE ECA17410 Be sure to put on safety goggles when work ing TIP Install the maste...

Page 102: ...dramatically shorten the drive chain s life 4 Adjust Drive chain slack Refer to DRIVE CHAIN SLACK on page 3 16 NOTICE ECA24590 A drive chain that is too tight will overload the engine and other vital...

Page 103: ...HE CLUTCH PLATES 5 1 CHECKING THE CLUTCH SPRINGS 5 1 CHECKING THE CLUTCH HOUSING 5 1 CHECKING THE CLUTCH BOSS 5 2 CHECKING THE PRESSURE PLATE 5 2 CHECKING THE PUSH LEVER SHAFT 5 2 CHECKING THE PUSH RO...

Page 104: ...ss gauge Out of specification Replace the clutch plates as a set EAM30111 CHECKING THE CLUTCH SPRINGS 1 Check Clutch spring Damage Replace the clutch springs as a set 2 Measure Clutch spring free leng...

Page 105: ...RY DRIVE GEAR 1 Check Primary drive gear Damage wear Replace the primary drive and primary driven gears as a set Excessive noise during operation Replace the primary drive and primary driven gears as...

Page 106: ...lutch boss nut 2 TIP Use the clutch holder 3 to hold the clutch boss 5 Bend the lock washer 1 tab 6 Install Friction plate 1 Clutch plate 2 TIP Install the clutch plates and friction plates alter nate...

Page 107: ...Tighten the bolts in stage using a crisscross pat tern 11 Install Dowel pin 1 Gasket clutch cover 2 12 Install Clutch cover Clutch cover bolt TIP Tighten the bolts in stage using a crisscross pat ter...

Page 108: ...CLUTCH 5 5 1 2...

Page 109: ...1 2 3 4 5 6 7 8 9 10 ELECTRICAL SYSTEM WIRING DIAGRAM 6 1 COLOR CODE 6 1...

Page 110: ...G L O W R Y G W B B W B B W B O B Y B B R R R G L B R W L B G W W R L Y B L L Y B B G L B R W L B G W W R 1 CDI unit 2 Engine stop switch 3 Ignition coil 4 Throttle position sensor 5 Solenoid valve 6...

Page 111: ...ERAL INFORMATION 7 1 TROUBLESHOOTING OF ENGINE 7 1 TROUBLESHOOTING OF CLUTCH 7 6 TROUBLESHOOTING OF TRANSMISSION 7 7 TROUBLESHOOTING OF COOLING SYSTEM 7 8 TROUBLESHOOTING OF BRAKE 7 9 TROUBLESHOOTING...

Page 112: ...icult to start but it cranks Symptom Possible cause Actions Spark plug does not produce a spark Have a Yamaha dealer check the electrical system Fuel not supplied Empty fuel tank Fill the fuel tank wi...

Page 113: ...cap Defective ignition coil Replace the ignition coil CDI unit failure Replace the CDI unit Fuel not supplied Fuel leakage Check the fuel passage Repair or replace as necessary Clogged carburetor fue...

Page 114: ...hose Replace the vacuum hose Damaged carburetor joint Replace the carburetor joint Loose carburetor joint Tighten the carburetor joint bolts to the specified torque Clogged air filter element Clean or...

Page 115: ...hten the main jet to the speci fied torque Bent damaged or worn jet needle Replace the jet needle Cracks or damage in the piston valve diaphragm Replace the piston valve dia phragm Problem with piston...

Page 116: ...rings as a set Worn or damaged piston Replace the piston and piston rings as a set Worn piston piston pin hole Replace the piston and piston pin as a set Worn or damaged piston pin Replace the piston...

Page 117: ...ne oil Deteriorated oil Change to recommended engine oil Clutch drags Faulty clutch spring Replace the clutch springs as a set Warped pressure plate Replace the pressure plate Swollen friction plate R...

Page 118: ...the shift drum Seized shift fork Replace the shift fork and shift fork guide bar as a set Bent shift fork guide bar Replace the shift fork guide bar Foreign object between transmis sion gears Remove...

Page 119: ...the radiator Damaged or faulty water pump Replace the water pump Damaged hoses or pipes Replace the hose or pipe Improperly connected hoses or pipes Connect the hoses and pipes properly Clogged air f...

Page 120: ...Damaged brake hose and brake pipe Replace the brake hose and brake pipe Oil or grease on the brake disc or brake pad Clean the brake disc or brake pad Insufficient lubrication of brake lever or brake...

Page 121: ...per rod assembly bolt Tighten the damper rod assembly bolt to the specified torque Damaged damper rod assembly bolt copper washer Replace the damper rod assembly bolt copper washer Cracked or damaged...

Page 122: ...ed torque Worn bearing or bearing race Replace the bearing and bearing race as a set Warped front fork Repair or replace the front fork Bent front wheel axle Replace the front wheel axle Incorrect tir...

Page 123: ...d or incorrect tire Replace the tire Loose wheel axle nut Tighten the wheel axle nut to the specified torque Loose swingarm pivot shaft Tighten the swingarm pivot shaft to the specified torque Bent or...

Page 124: ...TROUBLESHOOTING 7 13...

Page 125: ...PLES OF CARBURETOR SETTING 8 6 EXAMPLES OF CARBURETOR SETTING DEPENDING ON SYMPTOM 8 6 CHANGE OF THE HEAT RANGE OF SPARK PLUGS 8 8 CHASSIS 8 9 SELECTION OF THE SECONDARY REDUCTION RATIO SPROCKET 8 9 D...

Page 126: ...le to make a note of settings atmo spheric conditions road surface condition lap time etc so that the memorandum can be used as a reference useful for future EAM30591 ATMOSPHERIC CONDITIONS AND CARBUR...

Page 127: ...t by turning the pilot air screw 1 Turning in the pilot air screw will make the mix ture enrich at low speeds and turning it out will lean it For AUS NZL EAM30596 PILOT JET ADJUSTMENT The richness of...

Page 128: ...et needle 1 must be adjusted If the mixture is too rich or too lean at intermediate speed operation irregular engine operation and poor acceleration will result Whether or not the richness of the mixt...

Page 129: ...combination of the jet needle straight portion diameter taper starting position and clip position Example EAM30599 CARBURETOR SETTING PARTS A Lean larger diameter B Rich smaller diameter 1 1 8 thrott...

Page 130: ...14916 FE NYCE B4X 14916 CE NYDE B4X 14916 DE STD NYEE B4X 14916 EE NYFF B4X 14916 FF STD NYCF B4X 14916 CF NYDF B4X 14916 DF NYEF B4X 14916 EF NYFG B4X 14916 FG NYCG B4X 14916 CG NYDG B4X 14916 DG NY...

Page 131: ...2 NYDF 2 NYCF 3 NYDF 3 NYCF 2 B NYDE 2 NYEE 2 NYDE 1 NYEE 3 NYDE 2 NYEE 2 Pilot jet A 68 65 62 70 68 65 B 62 60 58 65 62 60 Pilot air screw A 0 0 0 0 0 0 B 0 0 0 0 0 0 Symptom Setting Checking At full...

Page 132: ...lip position is the jet needle groove on which the clip is installed The positions are numbered from the top It a change in the clip position 1 groove is effective try another jet needle that provides...

Page 133: ...No of the main jet must be changed by 30 it is advisable to change the heat range of spark plugs and newly select the proper main jet TIP When checking the discoloration of spark plugs be sure to stop...

Page 134: ...end of the straight line with care taken to avoid the en gine over revving TIP Riding technique varies from rider to rider and the performance of a machine also vary from machine to machine Therefore...

Page 135: ...the air spring characteristics to have a ten dency to be stiffer with the consequent dete riorated performance and characteristics Therefore adjust the front fork within the specified range EAM30173...

Page 136: ...rear fender 2 Remove the stand or block from the engine and with a rider astride the seat measure the sunken length b between the rear wheel axle center and mark of rear fender 3 Loosen the locknut 1...

Page 137: ...fol lowed more or less by a change in the compres sion damping force For correction adjust to decrease compression damping force WARNING EWA19200 When using a rear shock absorber other than currently...

Page 138: ...REAR SHOCK ABSORBER AS SEMBLY on page 3 20 Type Spring rate N mm Part number I D mark Q ty SOFT 44 5UN 22212 A0 Silver Green 2 46 5UN 22212 B0 Silver Red 2 48 5UN 22212 C0 Silver Black 2 50 5UN 22212...

Page 139: ...ticeable scars etc If any replace affected parts Slide metal Replace with a new one for extended use Piston metal Replace with a new one for extended use Lower bracket tightening torque Retighten to s...

Page 140: ...unt Increase oil amount by about 5 cm 0 2 US oz 0 2 Imp oz Obtrusive front tending to upper front posture Compression damping force Turn adjuster counterclockwise about 2 clicks to decrease damping Ba...

Page 141: ...senger is astride seat Spring Replace with soft spring Bottoming out High compres sion damping Turn adjuster clockwise about 1 6 turn to increase damping Spring set length Set sunken length for 90 100...

Page 142: ...CHASSIS 8 17...

Page 143: ......

Page 144: ...PRINTED IN JAPAN E...

Page 145: ...is manual should stay with this vehicle if it is sold Q Il convient de lire attentivement ce manuel avant la premi re utilisation du v hicule Le manuel doit tre remis avec le v hicule en cas de vente...

Page 146: ...this manual carefully before operating this vehicle Il convient de lire attentivement ce manuel avant la premi re utilisation du v hicule YZ125XP PRINTED IN JAPAN 2022 06 0 1 1 E F YZ125X 2023 YZ125X...