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EAS5WWL025 IMPORTANT This manual was produced by MBK Industrie. primarily for use by Yamaha and MBK dealers and their qualified mechanics. It is not possible to include all the knowledge of a mechanic in one manual. There- fore, anyone who uses this book to perform maintenance and repairs on Yamaha and MBK vehicles should have a basic understanding of mechanics and the techniques to repair these types of vehicles.
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EAS20090 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. •...
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EAS20101 SYMBOLS The following symbols are used in this manual for easier understanding. The following symbols are not relevant to every vehicle. SYMBOL DEFINITION SYMBOL DEFINITION Serviceable with engine mounted Gear oil Filling fluid Molybdenum disulfide oil Lubricant Brake fluid Special tool Wheel bearing grease Tightening torque...
EAS20110 TABLE OF CONTENTS GENERAL INFORMATION SPECIFICATIONS PERIODIC CHECKS AND ADJUSTMENTS CHASSIS ENGINE COOLING SYSTEM FUEL SYSTEM ELECTRICAL SYSTEM TROUBLESHOOTING...
GENERAL INFORMATION IDENTIFICATION .................... 1-1 VEHICLE IDENTIFICATION NUMBER .............1-1 MODEL LABEL..................1-1 FEATURES...................... 1-2 OUTLINE OF THE FI SYSTEM..............1-2 FI SYSTEM....................1-3 OUTLINE OF THE ABS (for YP125RA) ............ 1-4 ABS COMPONENT FUNCTIONS ............. 1-8 ABS OPERATION ...................1-14 ABS WARNING LIGHT AND OPERATION..........1-17 INSTRUMENT FUNCTIONS................1-18 IMPORTANT INFORMATION ...............
IDENTIFICATION EAS20130 IDENTIFICATION EAS20140 VEHICLE IDENTIFICATION NUMBER The vehicle identification number “1” is stamped into the frame. EAS20150 MODEL LABEL The model label “1” is affixed to the location shown. This information will be needed to order spare parts.
FEATURES EAS20170 FEATURES EAS37P1140 OUTLINE OF THE FI SYSTEM The main function of a fuel supply system is to provide fuel to the combustion chamber at the optimum air-fuel ratio in accordance with the engine operating conditions and the atmospheric temperature. In the conventional carburetor system, the air-fuel ratio of the mixture that is supplied to the combustion chamber is created by the volume of the intake air and the fuel that is metered by the jet used in the respective carburetor.
FEATURES EAS37P1141 FI SYSTEM The fuel pump delivers fuel to the fuel injector via the fuel filter. The pressure regulator maintains the fuel pressure that is applied to the fuel injector at a certain level. Accordingly, when the energizing signal from the ECU energizes the fuel injector, the fuel passage opens, causing the fuel to be injected into the intake manifold only during the time the passage remains open.
6. Hydraulic unit assembly (ABS ECU) The operation of the Yamaha ABS brakes is the same as conventional brakes on other vehicles, with a front brake lever for operating the front brake and a rear brake lever for operating the rear brake.
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FEATURES • Brake force: The force applied by braking to reduce the wheel speed. • Wheel lock: A condition that occurs when the rotation of one or both of the wheels has stopped, but the vehicle continues to travel. • Side force: The force on the tires which supports the vehicle when cornering.
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FEATURES Wheel slip and hydraulic control The ABS ECU calculates the wheel speed of each wheel according to the rotation signal received from the front and rear wheel sensors. In addition, the ABS ECU calculates the vehicle chassis speed and the rate of speed reduction based on the wheel speed values.
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Slip ratio (%) b. Brake force Electronic ABS features The Yamaha ABS (anti-lock brake system) has been developed with the most advanced electronic technology. The ABS control is processed with good response under various vehicle travel conditions. The ABS also includes a highly developed self-diagnosis function. The ABS detects any problem con- dition and allows normal braking even if the ABS is not operating properly.
FEATURES ABS block diagram 1. Front brake master cylinder 9. Buffer chamber 2. Hydraulic unit assembly 10. Front brake caliper 3. Rear brake master cylinder 11. Front wheel sensor 4. Inlet solenoid valve 12. ABS warning light 5. ABS motor 13.
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FEATURES 3. At low speed 7. Voltage 4. At high speed 8. Time 5. Wheel sensor 6. Wheel sensor rotor ABS warning light The ABS warning light “1” comes on to warn the rider if a malfunction in the ABS occurs. When the main switch is turned to “ON”, the ABS warning light comes on during the ABS self-diagnosis to check the electrical circuit of the light.
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FEATURES Hydraulic unit assembly The hydraulic unit assembly “1” is composed of hydraulic control valves (each with a outlet solenoid valve and inlet solenoid valve), buffer chambers, hydraulic pumps, an ABS motor, and ABS ECU. The hydraulic unit adjusts the front and rear wheel brake fluid pressure to control the wheel speed according to signals transmitted from the ABS ECU.
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FEATURES • Buffer chamber The buffer chamber accumulates the brake fluid that is depressurized while the ABS is operating. 1. Buffer chamber (pressurizing phase) 2. Buffer chamber (depressurizing phase) 3. Raised piston 1-11...
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FEATURES • ABS ECU The ABS ECU is integrated with the hydraulic unit to achieve a compact and lightweight design. As shown in the block following diagram, the ABS ECU receives wheel sensor signals from the front and rear wheels and also receives signals from other monitor circuits. 1.
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FEATURES • Some types of malfunctions are not recorded in the memory of the ABS ECU (e.g., a blown ABS ECU fuse). • The ABS performs a self-diagnosis test for a few seconds each time the vehicle first starts off after the main switch was turned on.
FEATURES EAS2DM1131 ABS OPERATION The ABS hydraulic circuit consists of two systems: the front wheel, and rear wheel. The following de- scribes the system for the front wheel only. Normal braking (ABS not activated) When the ABS is not activated, the inlet solenoid valve is open and the outlet solenoid valve is closed because a control signal has not been transmitted from the ABS ECU.
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FEATURES Emergency braking (ABS activated) 1. Depressurizing phase When the front wheel is about to lock, the outlet solenoid valve is opened by the “depressurization” signal transmitted from the ABS ECU. When this occurs, the inlet solenoid valve compresses the spring and closes the brake line from the brake master cylinder.
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FEATURES 2. Pressurizing phase The outlet solenoid valve is closed by the “pressurization” signal transmitted from the ABS ECU. At this time, the ABS ECU controls the opening of the inlet solenoid valve. As the inlet solenoid valve opens, the brake line from the brake master cylinder opens, allowing the brake fluid to be sent to the brake caliper.
FEATURES EAS2DM1119 ABS WARNING LIGHT AND OPERATION ABS function EWA2DM1011 WARNING • When hydraulic control is performed by the ABS, the brake system alerts the rider that the wheels have a tendency to lock by generating a reaction-force pulsating action in the front brake lever or rear brake lever.
INSTRUMENT FUNCTIONS To switch between miles and kilometers; hold EAS37P1080 INSTRUMENT FUNCTIONS the “SELECT” switch pushed, turn the main switch to “ON”, and keep the “SELECT” switch Multi-function display pushed for an additional 8 seconds. EWA12423 • For other countries, traveling speed, distance WARNING traveled and fuel consumption measurements Be sure to stop the vehicle before making...
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INSTRUMENT FUNCTIONS Odo (odometer) → Trip (tripmeter) → Trip Time With the key in the “ON” position, the fuel meter (time tripmeter) → Oil (oil change tripmeter) → indicates the amount of fuel in the fuel tank. The V-Belt (v-belt replacement tripmeter) → Odo display segments of the fuel meter disappear to- wards “E”...
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INSTRUMENT FUNCTIONS push the “RESET” button for at least 3 sec- V-belt replacement indicator “V-Belt” onds. The oil change tripmeter value will This indicator flashes every 18000 km (10500 mi flash. when the V-belt needs to be replaced. After changing the V-belt, reset the V-belt re- placement indicator.
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INSTRUMENT FUNCTIONS 1. Turn the key to “ON”. Push the “INFO” button to switch the display be- 2. Check that the V-belt replacement indicator tween the ambient temperature display “Air”, the comes on for a few seconds and then goes battery voltage, the average fuel consumption off.
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INSTRUMENT FUNCTIONS Refer to “CHECKING AND CHARGING THE The instantaneous fuel consumption display can BATTERY” on page 8-136. be set to either “km/L” or “L/100 km” (except for the UK). [Average fuel consumption mode] For the UK only: The instantaneous fuel consumption is dis- played “MPG”.
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INSTRUMENT FUNCTIONS [Warning message function] Warning message corresponding to the warning that you encounter. When two or more warning occur, warning mes- sage display shall be changed as follows: L FUEL → H TEMP → L BATT or H BATT → ICE →...
5. Keep all parts away from any source of fire. EAS20200 REPLACEMENT PARTS Use only genuine Yamaha parts for all replace- ments. Use oil and grease recommended by Yamaha for all lubrication jobs. Other brands may be similar in function and appearance, but inferior in quality.
IMPORTANT INFORMATION EAS20230 EAS2DM1132 BEARINGS AND OIL SEALS RUBBER PARTS Install bearings “1” and oil seals “2” so that the Check rubber parts for deterioration during in- manufacturer’s marks or numbers are visible. spection. Some of the rubber parts are sensitive When installing oil seals, lubricate the oil seal to gasoline, flammable oil, grease, etc.
BASIC SERVICE INFORMATION EAS30380 BASIC SERVICE INFORMATION EAS30390 QUICK FASTENERS Rivet type 1. Remove: • Quick fastener To remove the quick fastener, push its pin with a screwdriver, then pull the fastener out. Screw type 1. Remove: • Quick fastener To remove the quick fastener, loosen the screw with a screwdriver, then pull the fastener out.
BASIC SERVICE INFORMATION ECA16760 EAS30402 NOTICE ELECTRICAL SYSTEM Be sure to connect the battery leads to the correct battery terminals. Reversing the bat- Electrical parts handling tery lead connections could damage the ECA16600 NOTICE electrical components. Never disconnect a battery lead while the en- gine is running;...
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BASIC SERVICE INFORMATION ECA16620 Checking the electrical system NOTICE Handle electrical components with special Before checking the electrical system, make care, and do not subject them to strong sure that the battery voltage is at least 12 V. shocks. ECA16630 ECA14371 NOTICE NOTICE...
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BASIC SERVICE INFORMATION 2. Check: Checking the connections • Lead Check the leads, couplers, and connectors for • Coupler stains, rust, moisture, etc. • Connector 1. Disconnect: Moisture → Dry with an air blower. • Lead Rust/stains → Connect and disconnect sev- •...
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BASIC SERVICE INFORMATION The resistance values shown were obtained at the standard measuring temperature of 20 °C (68 °F). If the measuring temperature is not 20 °C (68 °F), the specified measuring conditions will be shown. Intake air temperature sensor re- sistance 5.40–6.60 kΩ...
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SPECIAL TOOLS EAS20260 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 inappropriate tools or improvised techniques. Special tools, part numbers or both may differ depending on the country. When placing an order, refer to the list provided below to avoid any mistakes.
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SPECIAL TOOLS Reference Tool name/Tool No. Illustration pages Yamaha diagnostic tool 4-65, 4-67, 90890-03215 8-99, 8-125 Damper rod holder 4-76, 4-78 90890-01294 Damping rod holder set YM-01300 YM-01300 T-handle 4-76, 4-78 90890-01326 T-handle 3/8" drive 60 cm long YM-01326 Fork seal driver weight...
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SPECIAL TOOLS Reference Tool name/Tool No. Illustration pages Yamaha bond No. 1215 5-12, 5-43, 90890-85505 5-59 (Three Bond No.1215®) Valve spring compressor 5-19, 5-24 90890-04019 YM-04019 Valve spring compressor attachment 5-19, 5-24 90890-04108 Valve spring compressor adapter 22 mm YM-04108 Valve guide remover (ø4.5)
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SPECIAL TOOLS Reference Tool name/Tool No. Illustration pages Sheave holder 5-33 90890-01701 Primary clutch holder YS-01880-A Locknut wrench 5-33, 5-37 90890-01348 YM-01348 Clutch spring holder 5-34, 5-37 90890-01337 Universal clutch compressor holder YM-33285 Clutch spring holder arm 5-34, 5-37 90890-01464 Compressor holder adapter YM-33285-6 Oil seal guide (ø41)
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SPECIAL TOOLS Reference Tool name/Tool No. Illustration pages Digital circuit tester 5-46, 8-145, 90890-03174 8-147 Model 88 Multimeter with tachometer YU-A1927 Crankcase separating tool 5-56 90890-01135 Crankcase separator YU-01135-B Crankshaft installer pot 5-58, 5-59 90890-01274 Installing pot YU-90058 YU-90058/YU-90059 Crankshaft installer bolt 5-58, 5-59 90890-01275 Bolt...
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ENGINE SPECIFICATIONS Radiator cap opening pressure 110.0–140.0 kPa (1.10–1.40 kgf/cm², 16.0–20.3 psi) Thermostat Valve opening temperature 70.5–73.5 °C (158.90–164.30 °F) Valve full open temperature 85.0 °C (185.00 °F) Valve lift (full open) 3.0 mm (0.12 in) Radiator core Width 244.0 mm (9.61 in) Height 158.0 mm (6.22 in) Depth...
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ENGINE SPECIFICATIONS Timing chain Tensioning system Automatic Rocker arm/rocker arm shaft Rocker arm inside diameter 9.985–10.000 mm (0.3931–0.3937 in) Limit 10.015 mm (0.3943 in) Rocker arm shaft outside diameter 9.966–9.976 mm (0.3924–0.3928 in) Limit 9.940 mm (0.3913 in) Rocker-arm-to-rocker-arm-shaft clearance 0.009–0.034 mm (0.0004–0.0013 in) Limit 0.075 mm (0.0030 in)
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ENGINE SPECIFICATIONS Spring rate K1 (exhaust) 23.54 N/mm (2.40 kgf/mm, 134.41 lbf/in) Spring rate K2 (exhaust) 36.58 N/mm (3.73 kgf/mm, 208.87 lbf/in) Installed compression spring force (intake) 140.00–162.00 N (14.28–16.52 kgf, 31.47– 36.42 lbf) Installed compression spring force (exhaust) 140.00–162.00 N (14.28–16.52 kgf, 31.47– 36.42 lbf) Spring tilt (intake) 2.5 °/1.8 mm (0.07 in)
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ENGINE SPECIFICATIONS End gap (installed) 0.35–0.50 mm (0.0138–0.0197 in) Limit 0.75 mm (0.0295 in) Ring side clearance 0.030–0.070 mm (0.0012–0.0028 in) Limit 0.120 mm (0.0047 in) Oil ring End gap (installed) 0.20–0.70 mm (0.0079–0.0276 in) Ring side clearance 0.060–0.150 mm (0.0024–0.0059 in) Crankshaft Width A 45.95–46.00 mm (1.809–1.811 in)
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ENGINE SPECIFICATIONS Decompression device Device type Auto decomp Air filter Air filter element Oil-coated paper element Fuel pump Pump type Electrical Maximum consumption amperage 1.9 A Fuel injector Model/quantity 1P51 / 1 12.0 Ω Resistance Throttle body Type/quantity EFI 1B91 / 1 ID mark 1B91 00 Throttle position sensor...
Ignition system Ignition system Advancer type Digital Ignition timing (B.T.D.C.) 8.0 °/1700 r/min Engine control unit Model/manufacturer YP125R 2DM0 / YAMAHA MOTOR ELECTRONICS YP125RA 2DM1 / YAMAHA MOTOR ELECTRONICS Ignition coil Minimum ignition spark gap 6.0 mm (0.24 in) 2.16–2.64 Ω...
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ELECTRICAL SPECIFICATIONS Meter lighting Indicator light Turn signal indicator light High beam indicator light Fuel level warning light Engine trouble warning light ABS warning light YP125RA LED Immobilizer system indicator light Electric starting system System type Constant mesh Starter motor Power output 0.25 kW 0.0378–0.0462 Ω...
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ELECTRICAL SPECIFICATIONS Backup fuse 10.0 A Radiator fan motor fuse 7.5 A ABS motor fuse YP125RA 30.0 A ABS solenoid fuse YP125RA 20.0 A ABS ECU fuse YP125RA 10.0 A Spare fuse 30.0 A Spare fuse 20.0 A Spare fuse 10.0 A Spare fuse 7.5 A...
TIGHTENING TORQUES EAS20320 TIGHTENING TORQUES EAS20330 GENERAL TIGHTENING TORQUE SPECIFICATIONS This chart specifies tightening torques for stan- dard fasteners with a standard ISO thread pitch. Tightening torque specifications for special com- ponents or assemblies are provided for each chapter of this manual. To avoid warpage, tight- en multi-fastener assemblies in a crisscross pat- tern and progressive stages until the specified tightening torque is reached.
LUBRICATION POINTS AND LUBRICANT TYPES EAS20360 LUBRICATION POINTS AND LUBRICANT TYPES EAS20370 ENGINE Lubrication point Lubricant Oil seal lips O-rings Bearings Cylinder head nut mounting surface Crankshaft pin Connecting rod big end thrust surface Oil pump drive gear inner surface Camshaft sprocket inner surface Piston pin and connecting rod small end Piston, piston rings, and cylinder inner surface...
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LUBRICATION POINTS AND LUBRICANT TYPES Lubrication point Lubricant BEL-RAY O-ring (clutch housing and secondary sheave) assembly lube® Yamaha bond Crankcase mating surfaces No.1215® Yamaha bond Crankshaft position sensor/stator assembly lead grommet No.1215® Yamaha bond Timing chain tensioner bolt No.1215® 2-23...
LUBRICATION POINTS AND LUBRICANT TYPES EAS20380 CHASSIS Lubrication point Lubricant Drive axle Engine mounting bolt Swingarm oil seal lips Steering bearings (upper and lower) Seat hinge spacer and bolt Seat lock sliding parts Front wheel oil seal lip and front wheel axle Speed sensor oil seal lip (for YP125R) Brake lever pivoting point and metal-to-metal moving parts Rear brake caliper retaining bolt...
CABLE ROUTING EAS20430 CABLE ROUTING Handlebar (top and front view) 2-29...
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CABLE ROUTING Front brake hose Throttle cable (decelerator cable) Rear brake hose Left handlebar switch lead Right handlebar switch lead Throttle cable (accelerator cable) Install the brake light switch connectors so that the leads are routed outward as shown in the illustration.
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CABLE ROUTING Steering head (front view) 2-31...
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CABLE ROUTING Front brake hose Rear brake hose Left front turn signal light lead Seat lock cable Fuel tank overflow hose Wire harness Speed sensor lead (for YP125R) Front wheel sensor lead (for YP125RA) Route the front brake hose in front of the rear brake hose.
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CABLE ROUTING Front brake (left side view) (for YP125R) 2-33...
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CABLE ROUTING Speed sensor lead Front brake hose Fasten the speed sensor lead to the front brake hose with the holders. Align the holders with the paint marks on the speed sensor lead. 25 mm (0.98 in) Fasten the speed sensor lead to the front brake hose with the holder.
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CABLE ROUTING Front brake (left side view) (for YP125RA) 2-35...
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CABLE ROUTING Front wheel sensor lead Brake hose (hydraulic unit to front brake caliper) Fasten the front wheel sensor lead to the brake hose (hydraulic unit to front brake caliper) with the holders. Align the holders with the paint marks on the front wheel sensor lead.
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CABLE ROUTING Engine and rear brake (left side and right side view) (for YP125R) 2-37...
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CABLE ROUTING Thermostat inlet hose Cylinder head breather hose Rear brake hose Align each holder with the portion of the cylinder head breather hose where the hose begins to bend. Install the air filter case joint screw clamp with the clamp screw head pointing upward.
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CABLE ROUTING Engine and rear brake (left side and right side view) (for YP125RA) 2-39...
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CABLE ROUTING Thermostat inlet hose Cylinder head breather hose Brake hose (hydraulic unit to rear brake caliper) Rear wheel sensor lead Align each holder with the portion of the cylinder head breather hose where the hose begins to bend. Install the air filter case joint screw clamp with the clamp screw head pointing upward.
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CABLE ROUTING Steering head (right side view) (for YP125R) 2-41...
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CABLE ROUTING Throttle cables Front brake hose Fuse boxes Headlight lead Starting circuit cut-off relay Headlight relay Radiator fan motor relay Turn signal/hazard relay Wire harness Rear brake hose Speed sensor lead coupler Main switch Right handlebar switch lead Left handlebar switch leads Route the handlebar switch leads to the inside of the meter cover, and then fasten the leads with a plastic locking tie.
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CABLE ROUTING Steering head (right side view) (for YP125RA) 2-43...
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CABLE ROUTING Throttle cables Brake hose (front brake master cylinder to hydraulic unit) ABS test coupler Hydraulic unit assembly Headlight lead Starting circuit cut-off relay 1 Headlight relay Radiator fan motor relay Turn signal/hazard relay Wire harness Brake hose (hydraulic unit to rear brake caliper) Front wheel sensor lead coupler Brake hose (hydraulic unit to front brake caliper) Main switch...
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CABLE ROUTING Frame (right side view) 2-45...
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CABLE ROUTING Rear brake hose Radiator fan motor lead Wire harness Rectifier/regulator Radiator inlet hose Radiator outlet hose Inside Outside 2-46...
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CABLE ROUTING Engine (right side view) 2-47...
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CABLE ROUTING License plate light lead Right tail/brake light lead Seat lock cable Rear brake hose (for YP125R) Ignition coil Wire harness sensor Right rear turn signal light lead Rear wheel sensor lead (for YP125RA) Brake hose (hydraulic unit to rear brake caliper) (for YP125RA) For YP125R For YP125RA...
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CABLE ROUTING Steering head (left side view) 2-49...
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CABLE ROUTING Starter relay Rear brake hose Left handlebar switch lead Wire harness Main switch Seat lock cable Throttle cables Starter motor lead Left front turn signal light lead Headlight lead Positive battery lead Fuse box lead (to ABS motor fuse and ABS solenoid fuse) Right handlebar switch lead Front brake hose...
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CABLE ROUTING Frame (left side view) 2-51...
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CABLE ROUTING Starter motor lead Throttle cables Seat lock cable Sidestand switch lead Rectifier/regulator Fuel tank overflow hose Wire harness Position the connector housing at the location shown between the frame tubes. Front side Inside Outside Fasten the coolant reservoir overflow hose and starter motor lead with the plastic band.
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CABLE ROUTING Engine (left side view) 2-53...
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CABLE ROUTING Seat lock cable Rear brake hose Wire harness Left tail/brake light lead Left rear turn signal light lead License plate light lead Starter motor lead Fuel hose Throttle cables Outside Inside 2-54...
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CABLE ROUTING Right front turn signal light Starting circuit cut-off relay Headlight relay Radiator fan motor relay Turn signal/hazard relay Fuse box Wire harness Front brake hose Right handlebar switch lead Rear brake hose Fuel hose Seat lock cable Starter motor lead Fuel pump lead Rear brake hose Left handlebar switch lead...
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CABLE ROUTING Engine and frame (top view) 2-57...
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CABLE ROUTING Wire harness Rear brake hose Crankshaft position sensor/stator coil assembly lead Right rear turn signal light lead Right tail/brake light lead License plate light lead Left tail/brake light lead Left rear turn signal light lead Seat lock cable Intake air temperature sensor lead Starter motor lead Fuel hose...
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CABLE ROUTING Rear brake (right side view) 2-59...
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CABLE ROUTING Rear wheel sensor lead (for YP125RA) Rear brake hose Brake hose (hydraulic unit to rear brake caliper) Fasten the grommets on the rear brake hose with the holders. For YP125R For YP125RA 2-60...
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CABLE ROUTING Hydraulic unit (for YP125RA) 2-61...
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CABLE ROUTING Brake hose (hydraulic unit to front brake caliper) Brake hose (front brake master cylinder to hydraulic unit) Brake hose (rear brake master cylinder to hydraulic unit) Brake hose (hydraulic unit to rear brake caliper) Hydraulic unit assembly Throttle cables Make sure to leave space between the brake hoses as shown in the illustration.
PERIODIC CHECKS AND ADJUSTMENTS PERIODIC MAINTENANCE ................3-1 INTRODUCTION ..................3-1 PERIODIC MAINTENANCE CHART FOR THE EMISSION CONTROL SYSTEM ....................3-1 GENERAL MAINTENANCE AND LUBRICATION CHART .......3-1 CHECKING THE FUEL LINE ..............3-4 CHECKING THE SPARK PLUG ............... 3-4 ADJUSTING THE VALVE CLEARANCE ..........3-4 CHECKING THE THROTTLE BODY JOINT AND INTAKE MANIFOLD...3-6 CHECKING THE BREATHER HOSE............3-7 CHECKING THE EXHAUST SYSTEM............3-7...
• From 30000 km (17500 mi), repeat the maintenance intervals starting from 6000 km (3500 mi). • Items marked with an asterisk should be performed by a Yamaha and MBK dealer as they require special tools, data and technical skills.
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PERIODIC MAINTENANCE ODOMETER READING CHECK OR MAINTENANCE ANNUAL ITEM CHECK 1000 km 6000 km 12000 km 18000 km 24000 km (600 mi) (3500 mi) (7000 mi) (10500 mi) (14000 mi) • Check for cracks or damage. √ √ √ √ √...
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PERIODIC MAINTENANCE EAU38263 • Engine air filter and V-belt air filters • This model’s engine air filter is equipped with a disposable oil-coated paper element, which must not be cleaned with compressed air to avoid damaging it. • The engine air filter element needs to be replaced and the V-belt air filter elements need to be ser- viced more frequently when riding in unusually wet or dusty areas.
PERIODIC MAINTENANCE EAS21030 CHECKING THE FUEL LINE 1. Remove: • Storage box Refer to “GENERAL CHASSIS” on page 4-1. 2. Check: • Fuel hose “1” Cracks/damage → Replace. Loose connections → Connect properly. 5. Clean: • Spark plug (with a spark plug cleaner or wire brush) 6.
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PERIODIC MAINTENANCE • When the valve clearance is to be measured or Valve clearance (cold) adjusted, the piston must be at top dead center Intake (TDC) on the compression stroke. 0.10–0.14 mm (0.0039–0.0055 in) 1. Remove: Exhaust 0.22–0.26 mm (0.0087–0.0102 in) •...
PERIODIC MAINTENANCE d. Hold the adjusting screw to prevent it from moving and tighten the locknut to specifica- tion. Locknut (valve clearance adjust- ing screw) 7 Nm (0.7 m·kgf, 5.1 ft·lbf) e. Measure the valve clearance again. f. If the valve clearance is still out of specifica- tion, repeat all of the valve clearance adjust- ▲...
PERIODIC MAINTENANCE FI diagnostic tool 90890-03182 YU-03182 FI Diagnostic Tool 1 5 5 0 r p m C1 : 10.Change the CO adjustment volume by press- ing the “UP” and “DOWN” buttons. The CO adjustment volume and engine idling speed appears on the LCD of the FI diagnostic 5.
PERIODIC MAINTENANCE 2. Check: • Air filter element After cleaning, gently squeeze the V-belt case Damage → Replace. air filter element to remove the excess solvent. ECA2DM1025 • Replace the air filter element every 12000 km NOTICE of operation. Do not twist the V-belt case air filter element •...
PERIODIC MAINTENANCE • When refilling, be careful that water does EAS21240 CHECKING THE BRAKE FLUID LEVEL not enter the brake master cylinder reser- 1. Stand the vehicle on a level surface. voir. Water will significantly lower the boil- ing point of the brake fluid and could cause •...
PERIODIC MAINTENANCE Brake caliper bleed screw 6 Nm (0.6 m·kgf, 4.3 ft·lbf) m. Fill the brake master cylinder reservoir to the proper level with the specified brake fluid. Refer to “CHECKING THE BRAKE FLUID LEVEL” on page 3-10. EWA13110 WARNING After bleeding the hydraulic brake system, check the brake operation.
PERIODIC MAINTENANCE 3. Hold the vehicle upright and apply the front brake several times. 4. Check: • Brake hose Brake fluid leakage → Replace the damaged hose. Refer to “FRONT BRAKE” on page 4-31. EAS21290 CHECKING THE REAR BRAKE HOSE 1.
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PERIODIC MAINTENANCE 1. Check: 2. Check: • Tire pressure • Tire surfaces Out of specification → Regulate. Damage/wear → Replace the tire. EWA13180 1. Tire tread depth WARNING 2. Side wall • The tire pressure should only be checked 3. Wear indicator and regulated when the tire temperature equals the ambient air temperature.
PERIODIC MAINTENANCE Tube wheel Tube tire only Tubeless wheel Tube or tubeless tire EWA2DM1017 WARNING After extensive tests, the tires listed below have been approved by MBK industrie for this model. The front and rear tires should al- ways be by the same manufacturer and of the same design.
PERIODIC MAINTENANCE e. Install the rubber washer. f. Install the center ring nut. g. Finger tighten the center ring nut, then align the slots of both ring nuts. If necessary, hold the lower ring nut and tighten the center ring nut until their slots are aligned.
PERIODIC MAINTENANCE Refer to “FRONT FORK” on page 4-74. EAS1SD1007 CHECKING THE SIDESTAND 1. Check: • Sidestand operation Check that the sidestand moves smoothly. Rough movement → Repair or replace. EAS21720 LUBRICATING THE SIDESTAND Lubricate the pivoting point, metal-to-metal mov- ing parts, and spring contact point of the side- stand.
PERIODIC MAINTENANCE EAS2DM1029 CHANGING THE ENGINE OIL Be sure to face the “ ” mark “a” on the oil filter 1. Start the engine, warm it up for several min- element cover in the direction shown in the illus- utes, and then turn it off. tration.
PERIODIC MAINTENANCE EAS21110 CHECKING THE COOLANT LEVEL Engine oil quantity 1. Stand the vehicle on a level surface. Without oil filter element replace- ment 1.40 L (1.48 US qt, 1.23 Imp.qt) • Place the vehicle on the centerstand. With oil filter element replace- •...
PERIODIC MAINTENANCE 8. Fill: • Use only distilled water. However, if dis- • Cooling system tilled water is not available, soft water may (with the specified amount of the recom- be used. mended coolant) • If coolant comes into contact with painted surfaces, immediately wash them with wa- Recommended antifreeze ter.
PERIODIC MAINTENANCE 2. Start the engine, warm it up for several min- 8. Start the engine, warm it up for several min- utes, and then turn it off. utes, and then turn it off. 3. Place a container under the final transmis- 9.
PERIODIC MAINTENANCE 2. Check: • Cable operation Rough movement → Lubricate. Recommended lubricant Engine oil or a suitable cable lu- bricant Hold the cable end upright and pour a few drops of lubricant into the cable sheath or use a suit- 4.
PERIODIC MAINTENANCE Faulty → Refer to “CHECKING THE 4. Remove: SWITCHES” on page 8-131 and “CHECK- • Headlight bulb holder “1” ING THE BULBS AND BULB SOCKETS” on • Headlight bulb page 8-134. EAS21810 ADJUSTING THE HEADLIGHT BEAM The following procedure applies to both of the headlights.
CHASSIS GENERAL CHASSIS..................4-1 INSTALLING THE STORAGE BOX ............4-10 REMOVING THE CENTER PANELS............4-10 INSTALLING THE CENTER PANELS ............4-10 REMOVING THE REAR UPPER COVER..........4-11 INSTALLING THE REAR UPPER COVER ..........4-11 REMOVING THE REAR PANELS............4-11 INSTALLING THE REAR PANELS ............4-12 REMOVING THE FRONT COWLING COVER AND UPPER PANEL ..................4-12 INSTALLING THE UPPER PANEL AND...
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FRONT BRAKE ..................... 4-31 INTRODUCTION ..................4-37 CHECKING THE FRONT BRAKE DISC ..........4-37 REPLACING THE FRONT BRAKE PADS ..........4-38 REMOVING THE FRONT BRAKE CALIPER..........4-39 DISASSEMBLING THE FRONT BRAKE CALIPER ........4-39 CHECKING THE FRONT BRAKE CALIPER ..........4-39 ASSEMBLING THE FRONT BRAKE CALIPER ........4-40 INSTALLING THE FRONT BRAKE CALIPER ........
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STEERING HEAD..................4-81 REMOVING THE LOWER BRACKET.............4-83 CHECKING THE STEERING HEAD ............4-83 INSTALLING THE STEERING HEAD .............4-83 REAR SHOCK ABSORBER ASSEMBLIES AND SWINGARM....4-85 REMOVING THE REAR SHOCK ABSORBER ASSEMBLIES ....4-87 REMOVING THE SWINGARM..............4-87 CHECKING THE REAR SHOCK ABSORBER ASSEMBLY ....4-87 CHECKING THE SWINGARM ..............4-87 MAINTENANCE OF THE REAR WHEEL SENSOR (for YP125RA) ..................
GENERAL CHASSIS EAS21830 GENERAL CHASSIS Removing the seat and center panels 10 Nm (1.0 m kgf, 7.2 ft Ibf) 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • • • 4.0 Nm (0.40 m kgf, 2.9 ft Ibf) • •...
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GENERAL CHASSIS Removing the rear panel and mudguard 23 Nm (2.3 m kgf, 17 ft Ibf) • • 2.3 Nm (0.23 m kgf, 1.7 ft Ibf) • • 4.0 Nm (0.40 m kgf, 2.9 ft Ibf) • • 2.3 Nm (0.23 m kgf, 1.7 ft Ibf) 10 Nm (1.0 m...
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GENERAL CHASSIS Removing the headlight assembly 4.0 Nm (0.40 m kgf, 2.9 ft Ibf) • • 0.4 Nm (0.04 m kgf, 0.29 ft Ibf) • • 2.3 Nm (0.23 m kgf, 1.7 ft Ibf) • • 7 Nm (0.7 m kgf, 5.1 ft Ibf) •...
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GENERAL CHASSIS Removing the windshield bracket 2.3 Nm (0.23 m kgf, 1.7 ft Ibf) • • 23 Nm (2.3 m kgf, 17 ft Ibf) 23 Nm (2.3 m kgf, 17 ft Ibf) • • • • 7 Nm (0.7 m kgf, 5.1 ft Ibf) •...
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GENERAL CHASSIS Removing the meter assembly 2.3 Nm (0.23 m kgf, 1.7 ft Ibf) • • 2.3 Nm (0.23 m kgf, 1.7 ft Ibf) • • 4.0 Nm (0.40 m kgf, 2.9 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Windshield...
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GENERAL CHASSIS Removing the radiator cover 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Front cowling Refer to “Removing the headlight assembly”. Front wheel Refer to “FRONT WHEEL” on page 4-17. Front fender Refer to “FRONT FORK”...
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GENERAL CHASSIS Removing the footrest board and leg shield 10 Nm (1.0 m kgf, 7.2 ft Ibf) 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • • • 7 Nm (0.7 m kgf, 5.1 ft Ibf) 7 Nm (0.7 m kgf, 5.1 ft Ibf) •...
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GENERAL CHASSIS Removing the air filter case assembly 9 Nm (0.9 m kgf, 6.5 ft Ibf) • • 9 Nm (0.9 m kgf, 6.5 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Refer to “Removing the seat and storage Storage box box”.
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GENERAL CHASSIS Removing the seat hinge 9 Nm (0.9 m kgf, 6.5 ft Ibf) • • 23 Nm (2.3 m kgf, 17 ft Ibf) • • 9 Nm (0.9 m kgf, 6.5 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Refer to “Removing the footrest board and...
GENERAL CHASSIS EAS1SD1020 INSTALLING THE STORAGE BOX 1. Install: • Storage box b. Unhook the projections on the center panel from the footrest board and sliding it upward. Storage box bolt 10 Nm (1.0 m·kgf, 7.2 ft·lbf) Tighten the storage box bolts in the proper tight- ening sequence as shown.
GENERAL CHASSIS b. Make sure that the projection on the center panel fits into the grommet in the rear panel. ▼ ▼▼▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼▼▼ a. Install the rear upper cover by fitting the pro- jection on the cover into the mudguard.
GENERAL CHASSIS EAS1SD1019 INSTALLING THE REAR PANELS The following procedure applies to both of the rear panels. 1. Install: • Rear panels b. Pull the upper panel forward to remove the projections from the slots in the front cowling and the grommet in the headlight assembly. ▼...
GENERAL CHASSIS b. Fit the projections on the front cowling cover into the holes in the upper panel and radiator cover. ▼ ▼▼▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼▼▼ a. Fit the 2 projections on the upper portion of the front upper panel into the holes in the front cowling.
GENERAL CHASSIS b. Pull the headlight assembly forward to re- move the projections from the grommets in the windshield bracket. ▲ ▲▲▲ ▲ ▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲▲▲ EAS1SD1044 REMOVING THE MAIN SWITCH COVER 1.
GENERAL CHASSIS in) hole through the seat hinge damper at a point 15–20 mm (0.59–0.79 in) from its end as shown. EWA13760 WARNING Wear eye protection to prevent eye damage from released gas or metal chips. ▼ ▼▼▼ ▼ ▼▼▼ ▼...
FRONT WHEEL EAS21870 FRONT WHEEL Removing the front wheel and brake discs (for YP125R) 40 Nm (4.0 m kgf, 29 ft Ibf) • • 59 Nm (5.9 m kgf, 43 ft Ibf) • • 23 Nm (2.3 m kgf, 17 ft Ibf) •...
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FRONT WHEEL Removing the front wheel and brake discs (for YP125RA) 40 Nm (4.0 m kgf, 29 ft Ibf) • • 59 Nm (5.9 m kgf, 43 ft Ibf) • • 7 Nm (0.7 m kgf, 5.1 ft Ibf) • •...
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FRONT WHEEL Disassembling the front wheel Order Job/Parts to remove Q’ty Remarks Oil seal Wheel bearing Spacer For assembly, reverse the disassembly pro- cedure. 4-19...
FRONT WHEEL EAS2DM1001 REMOVING THE FRONT WHEEL (for Place the vehicle on a suitable stand so that the YP125R) front wheel is elevated. 1. Stand the vehicle on a level surface. EWA13120 WARNING EAS21910 DISASSEMBLING THE FRONT WHEEL Securely support the vehicle so that there is 1.
FRONT WHEEL EAS2DM1003 MAINTENANCE OF THE FRONT WHEEL SENSOR AND SENSOR ROTOR (for YP125RA) ECA2DM1004 NOTICE • Handle the ABS components with care since they have been accurately adjusted. Keep them away from dirt and do not sub- ject them to shocks. •...
FRONT WHEEL 3. Measure: • Wheel sensor rotor deflection Install the wheel sensor rotor with the stamped Out of specification → Clean the installation mark “a” facing outward. surface of the wheel sensor rotor and correct the wheel sensor rotor deflection, or replace the wheel sensor rotor.
FRONT WHEEL e. When the wheel stops, put an “X ” mark at the bottom of the wheel. Place a suitable washer “1” between the socket “2” and the bearing so that both the inner race “3” and outer race “4” are pressed at the same time, and then press the bearing until the inner race makes contact with the spacer “5”.
FRONT WHEEL 4. Check: 2. Check: • Front wheel static balance • Front brake disc Refer to “CHECKING THE FRONT BRAKE ▼ ▼▼▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼▼▼ a. Turn the front wheel and make sure it stays at DISC”...
FRONT WHEEL 2. Check: ECA37P1030 NOTICE • Front brake disc Before tightening the wheel axle, push down Refer to “CHECKING THE FRONT BRAKE hard on the handlebar several times and DISC” on page 4-37. check if the front fork rebounds smoothly. 3.
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FRONT WHEEL Distance “a” (between the front wheel sensor rotor and front wheel sensor) 0.7–1.5 mm (0.028–0.059 in) Measure the distance between the front wheel sensor rotor and front wheel sensor in several places in one rotation of the front wheel. Do not turn the front wheel while the thickness gauge is installed.
REAR WHEEL EAS2DM1006 EAS2DM1008 REMOVING THE REAR WHEEL (DISC) (for MAINTENANCE OF THE REAR WHEEL YP125R) SENSOR ROTOR (for YP125RA) 1. Stand the vehicle on a level surface. ECA2DM1009 NOTICE EWA13120 WARNING • Handle the ABS components with care Securely support the vehicle so that there is since they have been accurately adjusted.
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REAR WHEEL 5. Measure: (for YP125RA) Rear brake disc bolt 23 Nm (2.3 m·kgf, 17 ft·lbf) Measure the distance “a” only if the wheel bear- LOCTITE® ings, wheel sensor rotor, or both were replaced. Rear wheel sensor rotor bolt (for YP125RA) •...
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FRONT BRAKE EAS22210 FRONT BRAKE Removing the front brake pads 40 Nm (4.0 m kgf, 29 ft Ibf) • • 18 Nm (1.8 m kgf, 13 ft Ibf) • • 2.5 Nm (0.25 m kgf, 1.8 ft Ibf) • • Order Job/Parts to remove Q’ty...
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FRONT BRAKE Removing the front brake master cylinder 1.8 Nm (0.18 m kgf, 1.3 ft Ibf) • • 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • 1.2 Nm (0.12 m kgf, 0.87 ft Ibf) •...
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FRONT BRAKE Removing the front brake master cylinder 1.8 Nm (0.18 m kgf, 1.3 ft Ibf) • • 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • 1.2 Nm (0.12 m kgf, 0.87 ft Ibf) •...
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FRONT BRAKE Disassembling the front brake master cylinder Order Job/Parts to remove Q’ty Remarks Brake master cylinder kit Brake master cylinder body For assembly, reverse the disassembly pro- cedure. 4-34...
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FRONT BRAKE Removing the front brake caliper 23 Nm (2.3 m kgf, 17 ft Ibf) • • 40 Nm (4.0 m kgf, 29 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Drain. Refer to “BLEEDING THE HYDRAULIC BRAKE SYSTEM (for YP125R)” on page Brake fluid 3-10 and “BLEEDING THE HYDRAULIC BRAKE SYSTEM (ABS) (for YP125RA)”...
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FRONT BRAKE Disassembling the front brake caliper 6 Nm (0.6 m kgf, 4.3 ft Ibf) • • 18 Nm (1.8 m kgf, 13 ft Ibf) • • 2.5 Nm (0.25 m kgf, 1.8 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Brake pad pin cap...
FRONT BRAKE EAS22220 INTRODUCTION EWA14101 WARNING Disc brake components rarely require disas- sembly. Therefore, always follow these pre- ventive measures: • Never disassemble brake components un- less absolutely necessary. • If any connection on the hydraulic brake system is disconnected, the entire brake ▲...
FRONT BRAKE d. Measure the brake disc deflection. ▼ ▼▼▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼▼▼ a. Connect a clear plastic hose “1” tightly to the e. If out of specification, repeat the adjustment bleed screw “2”.
FRONT BRAKE 5. Check: EWA1SD1006 WARNING • Brake lever operation Soft or spongy feeling → Bleed the brake sys- • Cover the brake caliper piston with a rag. Be careful not to get injured when the pis- tem. tons are expelled from the brake caliper. Refer to “BLEEDING THE HYDRAULIC •...
FRONT BRAKE ECA2DM1010 NOTICE When installing the brake hose onto the brake caliper, make sure the brake pipe “a” touches the projection “b” on the brake cali- per. 2. Check: • Brake caliper bracket Cracks/damage → Replace. EAS22400 ASSEMBLING THE FRONT BRAKE CALIPER EWA37P1011 WARNING 2.
FRONT BRAKE • When refilling, be careful that water does • Copper washers “2” not enter the brake master cylinder reser- • Front brake hose “3” voir. Water will significantly lower the boil- ing point of the brake fluid and could cause To collect any remaining brake fluid, place a vapor lock.
FRONT BRAKE EAS22530 INSTALLING THE FRONT BRAKE MASTER CYLINDER 1. Install: • Brake master cylinder “1” • Brake master cylinder holder Brake master cylinder holder bolt 7 Nm (0.7 m·kgf, 5.1 ft·lbf) 3. Fill: • Align the projection “a” on the brake master cyl- •...
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FRONT BRAKE 6. Check: • Brake lever operation Soft or spongy feeling → Bleed the brake sys- tem. Refer to “BLEEDING THE HYDRAULIC BRAKE SYSTEM (for YP125R)” on page 3-10 and “BLEEDING THE HYDRAULIC BRAKE SYSTEM (ABS) (for YP125RA)” on page 3-11.
REAR BRAKE EAS22550 REAR BRAKE Removing the rear brake pads (for YP125R) 14 Nm (1.4 m kgf, 10 ft Ibf) • • 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • 28 Nm (2.8 m kgf, 20 ft Ibf) •...
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REAR BRAKE Removing the rear brake pads (for YP125RA) 6 Nm (0.6 m kgf, 4.3 ft Ibf) • • 27 Nm (2.7 m kgf, 19 ft Ibf) • • 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks...
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REAR BRAKE Removing the rear brake master cylinder 1.8 Nm (0.18 m kgf, 1.3 ft Ibf) • • 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • 1.2 Nm (0.12 m kgf, 0.87 ft Ibf) •...
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REAR BRAKE Removing the rear brake master cylinder 1.8 Nm (0.18 m kgf, 1.3 ft Ibf) • • 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • 1.2 Nm (0.12 m kgf, 0.87 ft Ibf) •...
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REAR BRAKE Disassembling the rear brake master cylinder Order Job/Parts to remove Q’ty Remarks Brake master cylinder kit Brake master cylinder body For assembly, reverse the disassembly pro- cedure. 4-48...
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REAR BRAKE Removing the rear brake caliper (for YP125R) 21 Nm (2.1 m kgf, 15 ft Ibf) • • 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • 28 Nm (2.8 m kgf, 20 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks...
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REAR BRAKE Removing the rear brake caliper (for YP125RA) 21 Nm (2.1 m kgf, 15 ft Ibf) • • 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • 40 Nm (4.0 m kgf, 29 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks...
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REAR BRAKE Disassembling the rear brake caliper (for YP125R) 14 Nm (1.4 m kgf, 10 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Brake pad clip Brake pad pin Rear brake pad Brake pad spring Bleed screw/cap For assembly, reverse the disassembly pro- cedure.
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REAR BRAKE Disassembling the rear brake caliper (for YP125RA) 6 Nm (0.6 m kgf, 4.3 ft Ibf) • • 27 Nm (2.7 m kgf, 19 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Rear brake caliper retaining bolt Brake caliper bracket Rear brake pad Brake pad shim...
REAR BRAKE 5. Check: • Brake lever operation Always install new brake pads and a new brake Soft or spongy feeling → Bleed the brake sys- pad spring as a set. tem. ▼ ▼▼▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼...
REAR BRAKE b. Loosen the bleed screw and push the brake EAS2DM1009 REMOVING THE REAR BRAKE CALIPER caliper pistons into the brake caliper with your finger. Before removing the brake caliper, drain the brake fluid from the entire brake system. 1.
REAR BRAKE ▼ ▼▼▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼▼▼ a. Blow compressed air into the brake hose joint opening “a” to force out the pistons from the brake caliper. EWA13550 WARNING •...
REAR BRAKE 2. Check: ECA2DM1011 NOTICE • Brake caliper bracket Cracks/damage → Replace. While holding the brake hose, tighten the union bolt within the angle range shown in EAS22650 the illustration. ASSEMBLING THE REAR BRAKE CALIPER EWA2DM1003 WARNING • Before installation, all internal brake com- ponents should be cleaned and lubricated with clean or new brake fluid.
REAR BRAKE ECA13540 ECA14170 NOTICE NOTICE Brake fluid may damage painted surfaces When installing the brake hose onto the and plastic parts. Therefore, always clean up brake caliper “1”, make sure the brake pipe any spilt brake fluid immediately. “a” touches the projection “b” on the brake caliper.
REAR BRAKE • When refilling, be careful that water does not enter the brake master cylinder reser- To collect any remaining brake fluid, place a voir. Water will significantly lower the boil- container under the master cylinder and the end ing point of the brake fluid and could cause of the brake hose.
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REAR BRAKE 6. Check: • Brake lever operation Soft or spongy feeling → Bleed the brake sys- tem. Refer to “BLEEDING THE HYDRAULIC BRAKE SYSTEM (for YP125R)” on page 3-10 and “BLEEDING THE HYDRAULIC BRAKE SYSTEM (ABS) (for YP125RA)” on page 3-11.
ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) EAS2DM1016 REMOVING THE HYDRAULIC UNIT Do not operate the brake levers while removing ASSEMBLY the brake hoses. ECA2DM1012 NOTICE ECA2DM1014 Unless necessary, avoid removing and in- NOTICE stalling the brake hoses of the hydraulic unit When removing the brake hoses, cover the assembly.
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Do not allow any foreign materials to enter the hydraulic unit assembly or the brake hoses when installing the hydraulic unit assembly. ECA2DM1015 NOTICE Do not remove the rubber plugs or bolts (M10 × 1.25) installed in the flare nut holes before installing the hydraulic unit assem- bly.
Securely support the vehicle so that there is no danger of it falling over. • For the brake line routing confirmation, use the 6. Start the Yamaha diagnostic tool and display diagnosis mode of the Yamaha diagnostic tool. the diagnosis mode screen.
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Securely support the vehicle so that there is no danger of it falling over. • For the ABS reaction-force confirmation, use the diagnosis mode of the Yamaha diagnostic tool. For more information, refer to the opera- tion manual of the Yamaha diagnostic tool.
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• The reaction-force pulsating action consists of quick pulses. • Be sure to continue operating the front brake 6. Start the Yamaha diagnostic tool and display lever and rear brake lever even after the pul- the diagnosis mode screen. sating action has stopped.
12.Turn the main switch to “OFF”. 13.Remove the Yamaha diagnostic tool coupler from the ABS test coupler, and then install the protective cap. 14.Turn the main switch to “ON”.
HANDLEBAR EAS22840 HANDLEBAR Removing the handlebar 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • 23 Nm (2.3 m kgf, 17 ft Ibf) • • 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • 12 Nm (1.2 m kgf, 8.7 ft Ibf) •...
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HANDLEBAR Removing the handlebar 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • 23 Nm (2.3 m kgf, 17 ft Ibf) • • 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • 12 Nm (1.2 m kgf, 8.7 ft Ibf) •...
HANDLEBAR EAS22860 REMOVING THE HANDLEBAR The upper handlebar holders should be installed 1. Stand the vehicle on a level surface. with the arrow marks “a” facing forward “A”. EWA13120 WARNING Securely support the vehicle so that there is no danger of it falling over. 2.
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HANDLEBAR EWA13700 WARNING • Be sure to position the washer between the Do not touch the handlebar grip until the rub- throttle grip and the right handlebar switch. ber adhesive has fully dried. • Lubricate the end of the throttle cables and the d.
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HANDLEBAR 9. Adjust: • Throttle grip free play Refer to “CHECKING THE THROTTLE GRIP OPERATION” on page 3-24. Throttle grip free play 3.0–5.0 mm (0.12–0.20 in) 4-73...
FRONT FORK EAS22950 FRONT FORK Removing the front fork legs 40 Nm (4.0 m kgf, 29 ft Ibf) • • 23 Nm (2.3 m kgf, 17 ft Ibf) • • 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • 9 Nm (0.9 m kgf, 6.5 ft Ibf)
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FRONT FORK Disassembling the front fork legs 30 Nm (3.0 m kgf, 22 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks The following procedure applies to both of the front fork legs. Fork spring Dust seal Oil seal clip Damper rod bolt Copper washer Damper rod...
FRONT FORK EAS22960 REMOVING THE FRONT FORK LEGS The following procedure applies to both of the front fork legs. 1. Stand the vehicle on a level surface. EWA13120 WARNING Securely support the vehicle so that there is no danger of it falling over. 2.
FRONT FORK EAS23030 ASSEMBLING THE FRONT FORK LEGS The following procedure applies to both of the front fork legs. EWA13660 WARNING • Make sure the oil levels in both front fork legs are equal. • Uneven oil levels can result in poor han- dling and a loss of stability.
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FRONT FORK While holding the damper rod with the damper rod holder “2” and T-handle “3”, tighten the damper rod bolt. Damper rod holder 90890-01294 Damping rod holder set YM-01300 T-handle 90890-01326 T-handle 3/8" drive 60 cm long YM-01326 5. Install: •...
FRONT FORK 10.Measure: • Front fork leg oil level “a” (from the top of the inner tube, with the inner tube fully compressed and without the fork spring) Out of specification → Correct. Level 109.0 mm (4.29 in) 7. Fill: •...
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FRONT FORK Pull up the inner tube until it stops, and then tighten the lower bracket pinch bolts. Lower bracket pinch bolt 23 Nm (2.3 m·kgf, 17 ft·lbf) 2. Lower bracket 2. Install: • Cap bolt (along with the O-ring Cap bolt 40 Nm (4.0 m·kgf, 29 ft·lbf) •...
STEERING HEAD EAS23090 STEERING HEAD Removing the lower bracket 120 Nm (12 m kgf, 87 ft lbf) • • 75 Nm (7.5 m kgf, 54 ft Ibf) • • 1st 38 Nm (3.8 m kgf, 27 ft lbf) • • 2nd 22 Nm (2.2 m kgf, 16 ft lbf)
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STEERING HEAD Removing the lower bracket 120 Nm (12 m kgf, 87 ft lbf) • • 75 Nm (7.5 m kgf, 54 ft Ibf) • • 1st 38 Nm (3.8 m kgf, 27 ft lbf) • • 2nd 22 Nm (2.2 m kgf, 16 ft lbf) •...
STEERING HEAD ▼ ▼▼▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼▼▼ EAS23110 REMOVING THE LOWER BRACKET a. Remove the bearing races from the steering 1. Stand the vehicle on a level surface. head pipe “1”...
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STEERING HEAD • Rubber washer • Center ring nut “2” • Lock washer “3” • Upper ring nut “4” Refer to “CHECKING AND ADJUSTING THE STEERING HEAD” on page 3-15. 3. Install: • Woodruff key “1” • Lower handlebar holder “2” •...
REAR SHOCK ABSORBER ASSEMBLIES AND SWINGARM EAS23220 EAS23240 REMOVING THE REAR SHOCK ABSORBER CHECKING THE REAR SHOCK ABSORBER ASSEMBLIES ASSEMBLY 1. Stand the vehicle on a level surface. 1. Check: EWA13120 • Rear shock absorber rod WARNING Bends/damage → Replace the rear shock Securely support the vehicle so that there is absorber assembly.
ENGINE ENGINE INSPECTION ..................5-1 MEASURING THE COMPRESSION PRESSURE........5-1 ENGINE REMOVAL ..................5-2 INSTALLING THE ENGINE............... 5-5 CYLINDER HEAD.................... 5-7 REMOVING THE CYLINDER HEAD............5-9 CHECKING THE CYLINDER HEAD ............5-9 CHECKING THE CAMSHAFT SPROCKET..........5-10 CHECKING THE TIMING CHAIN TENSIONER........5-10 INSTALLING THE CYLINDER HEAD .............5-11 CAMSHAFT ....................
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V-BELT AUTOMATIC TRANSMISSION ............5-30 REMOVING THE PRIMARY SHEAVE............5-33 REMOVING THE SECONDARY SHEAVE ..........5-33 DISASSEMBLING THE SECONDARY SHEAVE........5-34 CHECKING THE CLUTCH HOUSING ............5-34 CHECKING THE CLUTCH SHOES ............5-34 CHECKING THE V-BELT................5-34 CHECKING THE PRIMARY SHEAVE ............5-35 CHECKING THE PRIMARY SHEAVE WEIGHTS........5-35 CHECKING THE PRIMARY SHEAVE SLIDERS ........
ENGINE REMOVAL EAS23710 ENGINE REMOVAL Removing the muffler and exhaust pipe 53 Nm (5.3 m kgf, 38 ft Ibf) • • 14 Nm (1.4 m kgf, 10 ft Ibf) 20 Nm (2.0 m kgf, 14 ft Ibf) • • • •...
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ENGINE REMOVAL Disconnecting the leads and hoses 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Drain. Engine oil Refer to “CHANGING THE ENGINE OIL” on page 3-19. Drain. Coolant Refer to “CHANGING THE COOLANT” on page 3-21.
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ENGINE REMOVAL Removing the engine 59 Nm (5.9 m kgf, 43 ft Ibf) • • 32 Nm (3.2 m kgf, 23 ft Ibf) • • 29 Nm (2.9 m kgf, 21 ft Ibf) • • 64 Nm (6.4 m kgf, 46 ft Ibf) •...
CYLINDER HEAD EAS24100 CYLINDER HEAD Removing the cylinder head 10 Nm (1.0 m kgf, 7.2 ft Ibf) 8 Nm (0.8 m kgf, 5.8 ft Ibf) 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • • • • • 13 Nm (1.3 m kgf, 9.4 ft Ibf) •...
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CYLINDER HEAD Removing the cylinder head 10 Nm (1.0 m kgf, 7.2 ft Ibf) 8 Nm (0.8 m kgf, 5.8 ft Ibf) 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • • • • • 13 Nm (1.3 m kgf, 9.4 ft Ibf) •...
CYLINDER HEAD EAS2DM1032 REMOVING THE CYLINDER HEAD 1. Align: • “I” mark “a” on the generator rotor (with the stationary pointer “b” on the genera- tor cover) ▼ ▼▼▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼...
CYLINDER HEAD c. If the limit is exceeded, resurface the cylinder head as follows. Do not use a sharp instrument to avoid damag- d. Place 400–600 grit wet sandpaper on the sur- ing or scratching: face plate and resurface the cylinder head •...
CYLINDER HEAD b. Align the “I” mark “a” on the generator rotor with the stationary pointer “b” on the genera- tor cover. c. Install the timing chain “1” onto the camshaft sprocket “2”, then the camshaft sprocket onto the camshaft, and then finger tighten the camshaft sprocket bolt.
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Install the gasket and the timing chain ten- sioner “2” onto the cylinder. EWA2DM1012 WARNING Always use a new gasket. Apply sealant to the threads of the timing chain tensioner bolts. Yamaha bond No. 1215 90890-85505 (Three Bond No.1215®) 5-12...
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CYLINDER HEAD 6. Tighten: • Camshaft sprocket bolt Camshaft sprocket bolt 30 Nm (3.0 m·kgf, 22 ft·lbf) ECA2DM1031 NOTICE Be sure to tighten the camshaft sprocket bolt to the specified torque to avoid the possibil- ity of the bolt coming loose and damaging the engine.
CAMSHAFT EAS23760 CAMSHAFT Removing the rocker arms and camshaft 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks...
CAMSHAFT EAS2DM1036 REMOVING THE CAMSHAFT 1. Remove: • Camshaft “1” Screw an M8 bolt “2” into the threaded end of the camshaft, and then pull out the camshaft. EAS2DM1037 CHECKING THE CAMSHAFT 1. Check: 3. Check: • Camshaft lobes Blue discoloration/pitting/scratches → Re- •...
VALVES AND VALVE SPRINGS EAS24270 VALVES AND VALVE SPRINGS Removing the valves and valve springs Order Job/Parts to remove Q’ty Remarks Cylinder head Refer to “CYLINDER HEAD” on page 5-7. Rocker arms/Camshaft Refer to “CAMSHAFT” on page 5-14. Valve cotter Upper spring seat Valve spring Intake valve...
VALVES AND VALVE SPRINGS EAS37P1014 REMOVING THE VALVES The following procedure applies to all of the valves and related components. Before removing the internal parts of the cylinder head (e.g., valves, valve springs, valve seats), make sure the valves properly seal. 1.
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VALVES AND VALVE SPRINGS b. Install the new valve guide with the valve Valve-stem-to-valve-guide clear- guide installer “2” and valve guide remover ance (intake) “1”. 0.010–0.037 mm (0.0004–0.0015 Valve guide position Limit Intake 0.080 mm (0.0032 in) 17.0–17.4 mm (0.670–0.685 in) Valve-stem-to-valve-guide clear- Exhaust ance (exhaust)
VALVES AND VALVE SPRINGS i. Press the valve through the valve guide and ECA13790 NOTICE onto the valve seat to make a clear impres- Do not let the lapping compound enter the sion. gap between the valve stem and the valve j.
VALVES AND VALVE SPRINGS Recommended lubricant Molybdenum disulfide oil b. Installed length 3. Measure: • Valve spring tilt “a” Out of specification → Replace the valve 3. Install: • Lower spring seat “1” spring. • Valve stem seal “2” Spring tilt (intake) •...
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VALVES AND VALVE SPRINGS Install the valve cotters by compressing the valve spring with the valve spring compressor and the valve spring compressor attachment “2”. Valve spring compressor 90890-04019 YM-04019 Valve spring compressor attach- ment 90890-04108 Valve spring compressor adapt- er 22 mm YM-04108 5.
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CYLINDER AND PISTON EAS24350 CYLINDER AND PISTON Removing the cylinder and piston 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Cylinder head Refer to “CYLINDER HEAD” on page 5-7. Timing chain guide (exhaust side) Cylinder Cylinder gasket Dowel pin...
CYLINDER AND PISTON EAS2DM1045 REMOVING THE PISTON When removing a piston ring, open the end gap 1. Remove: with your fingers and lift the other side of the ring • Piston pin clips “1” over the piston crown. • Piston pin “2” •...
CYLINDER AND PISTON EAS2DM1047 CHECKING THE PISTON RINGS 1. Measure: • Piston ring side clearance Out of specification → Replace the piston and piston rings as a set. Before measuring the piston ring side clearance, eliminate any carbon deposits from the piston ring grooves and piston rings.
CYLINDER AND PISTON 3. Measure: 3. Measure: • Piston ring end gap • Piston pin bore diameter “b” Out of specification → Replace the piston Out of specification → Replace the piston. ring. Piston pin bore inside diameter 14.002–14.013 mm (0.5513– The oil ring expander spacer end gap cannot be 0.5517 in) measured.
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CYLINDER AND PISTON 120˚ 120˚ 120˚ 2. Install: a. Top ring • Piston “1” b. Upper oil ring rail • Piston pin “2” c. Oil ring expander d. Lower oil ring rail • Piston pin clips “3” e. 2nd ring f.
V-BELT AUTOMATIC TRANSMISSION EAS24610 V-BELT AUTOMATIC TRANSMISSION Removing the V-belt case cover 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Refer to “GENERAL CHASSIS” on page Left center panel/Air filter case 4-1.
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V-BELT AUTOMATIC TRANSMISSION Removing the V-belt, primary sheave and secondary sheave 55 Nm (5.5 m kgf, 40 ft Ibf) • • 60 Nm (6.0 m kgf, 43 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Primary sheave nut/Washer Primary fixed sheave Washer Secondary sheave nut...
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V-BELT AUTOMATIC TRANSMISSION Disassembling the secondary sheave 90 Nm (9.0 m kgf, 65 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Clutch carrier nut Clutch carrier Clip Clutch carrier plate Clutch shoe spring Compression spring Spring seat Guide pin Secondary sliding sheave O-ring Oil seal...
V-BELT AUTOMATIC TRANSMISSION EAS2DM1051 REMOVING THE PRIMARY SHEAVE 1. Remove: • V-belt case Loosen each bolt 1/4 of a turn at a time, in stag- es and in a crisscross pattern. After all of the bolts are fully loosened, remove them. 2.
V-BELT AUTOMATIC TRANSMISSION EAS2DM1053 EAS2DM1054 DISASSEMBLING THE SECONDARY CHECKING THE CLUTCH SHOES SHEAVE The following procedure applies to all of the 1. Remove: clutch shoes. • Clutch carrier nut “1” 1. Check: • Clutch shoe Damage/wear → Replace the clutch shoes While compressing the compression spring with and springs as a set.
STARTER CLUTCH AND GENERATOR EAS24520 STARTER CLUTCH AND GENERATOR Removing the generator cover and stator coil 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • 10 Nm (1.0 m kgf, 7.2 ft Ibf) •...
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STARTER CLUTCH AND GENERATOR Removing the generator rotor and starter clutch 13 Nm (1.3 m kgf, 9.4 ft Ibf) • • 80 Nm (8.0 m kgf, 58 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Circlip Washer Starter clutch idle gear shaft Starter clutch idle gear Generator rotor Woodruff key...
STARTER CLUTCH AND GENERATOR EAS2DM1063 REMOVING THE GENERATOR 1. Remove: • Generator cover Loosen each bolt 1/4 of a turn at a time, in stag- es and in a crisscross pattern. After all of the bolts are fully loosened, remove them. 2.
STARTER CLUTCH AND GENERATOR • While holding the generator rotor “2” with the sheave holder “3”, tighten the starter clutch bolts. • Do not allow the sheave holder to touch the projection on the generator rotor. Sheave holder 90890-01701 Primary clutch holder 2.
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Tighten the generator cover bolts in stages and in a crisscross pattern. 3. Apply: • Sealant (onto the crankshaft position sensor/stator assembly lead grommet) Yamaha bond No. 1215 90890-85505 (Three Bond No.1215®) 4. Install: • Oil seal “1” Oil seal installed depth 4.5–5.4 mm (0.18–0.21 in)
ELECTRIC STARTER EAS2DM1030 ELECTRIC STARTER Removing the starter motor 7 Nm (0.7 m kgf, 5.1 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Refer to “GENERAL CHASSIS” on page Storage box/Air filter case 4-1. Starter motor lead Disconnect. Ground lead Disconnect.
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ELECTRIC STARTER Disassembling the starter motor Order Job/Parts to remove Q’ty Remarks O-ring Starter motor yoke O-ring Armature assembly Shim Brush Spring Front bracket/brush holder set For assembly, reverse the disassembly pro- cedure. 5-45...
ELECTRIC STARTER EAS2DM1068 CHECKING THE STARTER MOTOR Digital circuit tester 1. Check: 90890-03174 • Commutator Model 88 Multimeter with ta- Dirt → Clean with 600 grit sandpaper. chometer YU-A1927 2. Measure: • Commutator diameter “a” Out of specification → Replace the starter Armature coil motor.
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ELECTRIC STARTER 7. Check: • Gear teeth Damage/wear → Replace the gear. 8. Check: • Bearing • Oil seal • Bushing Damage/wear → Replace the defective part(s). 5-47...
OIL PUMP EAS24910 OIL PUMP Removing the oil pump 4 Nm (0.4 m kgf, 2.9 ft Ibf) • • 12 Nm (1.2 m kgf, 8.7 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Refer to “STARTER CLUTCH AND GENER- Starter clutch gear ATOR”...
OIL PUMP When installing the inner rotor, align the pin “4” in the oil pump driven gear with the groove “a” in the inner rotor. 4. Check: • Oil pump operation Refer to “CHECKING THE OIL PUMP” on page 5-49. EAS2DM1071 INSTALLING THE OIL PUMP 1.
TRANSMISSION EAS26240 TRANSMISSION Removing the transmission 16 Nm (1.6 m kgf, 12 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Rear wheel Refer to “REAR WHEEL” on page 4-27. Drain. Final transmission oil Refer to “CHANGING THE FINAL TRANS- MISSION OIL”...
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TRANSMISSION Removing the transmission 16 Nm (1.6 m kgf, 12 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Drive axle For installation, reverse the removal proce- dure. 5-52...
TRANSMISSION EAS2DM1072 REMOVING THE TRANSMISSION 1. Remove: • Transmission case cover Loosen each bolt 1/4 of a turn at a time, in stag- es and in a crisscross pattern. After all of the bolts are fully loosened, remove them. EAS2DM1073 CHECKING THE TRANSMISSION 1.
CRANKSHAFT EAS2DM1031 CRANKSHAFT Removing the crankshaft 20 Nm (2.0 m kgf, 14 ft Ibf) • • 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • 32 Nm (3.2 m kgf, 23 ft Ibf) • • 10 Nm (1.0 m kgf, 7.2 ft Ibf) •...
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CRANKSHAFT Removing the crankshaft 20 Nm (2.0 m kgf, 14 ft Ibf) • • 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • 32 Nm (3.2 m kgf, 23 ft Ibf) • • 10 Nm (1.0 m kgf, 7.2 ft Ibf) •...
CRANKSHAFT EAS2DM1075 ECA2DM1038 DISASSEMBLING THE CRANKCASE NOTICE 1. Remove: • To protect the end of the crankshaft, place • Crankcase bolts an appropriate sized socket “4” between the crankcase separating tool bolt and the Loosen each bolt 1/4 of a turn at a time, in stag- crankshaft.
CRANKSHAFT • Bearing “2” Camshaft runout limit Cracks/damage/wear → Replace the crank- 0.030 mm (0.0012 in) shaft. 5. Check: 2. Measure: • Crankshaft journal • Big end side clearance Scratches/wear → Replace the crankshaft. Out of specification → Replace the crank- •...
• M6 × 70 mm (2.76 in) bolts: “3” 2. Apply: • Sealant (onto the crankcase mating surfaces) Yamaha bond No. 1215 90890-85505 (Three Bond No.1215®) Do not allow any sealant to come into contact with the oil gallery.
COOLING SYSTEM RADIATOR ...................... 6-1 CHECKING THE RADIATOR..............6-2 INSTALLING THE RADIATOR..............6-2 THERMOSTAT ....................6-4 CHECKING THE THERMOSTAT.............. 6-5 INSTALLING THE THERMOSTAT ASSEMBLY ........6-5 WATER PUMP....................6-6 DISASSEMBLING THE WATER PUMP............ 6-7 CHECKING THE WATER PUMP .............. 6-7 ASSEMBLING THE WATER PUMP............6-7 INSTALLING THE WATER PUMP ............
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RADIATOR EAS26380 RADIATOR Removing the radiator 2.0 Nm (0.20 m kgf, 1.4 ft Ibf) 13 Nm (1.3 m kgf, 9.4 ft Ibf) • • • • Order Job/Parts to remove Q’ty Remarks Refer to “GENERAL CHASSIS” on page Radiator cover/Leg shield 4-1.
RADIATOR EAS26390 CHECKING THE RADIATOR 1. Check: • Radiator fins Obstruction → Clean. Apply compressed air to the rear of the radia- tor. Damage → Repair or replace. Straighten any flattened fins with a thin, flathead screwdriver. b. Apply the specified pressure for ten seconds and make sure there is no drop in pressure.
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RADIATOR 3. Measure: • Radiator cap opening pressure Below the specified pressure → Replace the radiator cap. Refer to “CHECKING THE RADIATOR” on page 6-2.
THERMOSTAT EAS26440 THERMOSTAT Removing the thermostat 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks Refer to “GENERAL CHASSIS” on page Storage box 4-1. Drain. Coolant Refer to “CHANGING THE COOLANT” on page 3-21. Thermostat outlet hose Disconnect.
THERMOSTAT 2. Check: EAS26450 CHECKING THE THERMOSTAT • Thermostat cover 1. Check: Cracks/damage → Replace. • Thermostat “1” Does not open at 70.5–73.5°C (159–164°F) EAS26480 INSTALLING THE THERMOSTAT → Replace. ASSEMBLY 1. Install: • Thermostat “1” • Thermostat cover Install the thermostat with its breather hole “a” in the position shown in the illustration.
WATER PUMP EAS26500 WATER PUMP Removing the water pump 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • Order Job/Parts to remove Q’ty Remarks...
WATER PUMP EAS2DM1085 DISASSEMBLING THE WATER PUMP Install the water pump seal with the special tools 1. Remove: to the specified depth as shown in the illustra- • Water pump seal “1” tion. Remove the water pump seal from the inside of Installed depth of water pump the water pump housing “2”.
WATER PUMP • Water pump housing plate 2 “2” 2. Fill: • Water pump housing plate 1 “3” • Cooling system (with the specified amount of the recom- Water pump housing plate 1 bolt mended coolant) 10 Nm (1.0 m·kgf, 7.2 ft·lbf) Refer to “CHANGING THE COOLANT”...
FUEL SYSTEM FUEL TANK..................... 7-1 REMOVING THE FUEL TANK ..............7-2 REMOVING THE FUEL PUMP ..............7-2 CHECKING THE FUEL PUMP BODY............7-2 INSTALLING THE FUEL PUMP..............7-2 INSTALLING THE FUEL TANK..............7-2 CHECKING THE FUEL PRESSURE ............7-3 THROTTLE BODY................... 7-4 REMOVING THE FUEL HOSE ..............7-6 CHECKING THE FUEL INJECTOR ............
FUEL TANK EAS26620 FUEL TANK Removing the fuel tank 10 Nm (1.0 m kgf, 7.2 ft Ibf) • • 14 Nm (1.4 m kgf, 10 ft Ibf) • • 6 (6) 7 Nm (0.7 m kgf, 5.1 ft Ibf) • •...
FUEL TANK • Do not touch the base section of the fuel EAS26630 REMOVING THE FUEL TANK sender. 1. Extract the fuel in the fuel tank through the fuel tank filler hole with a pump. EAS26670 2. Disconnect: CHECKING THE FUEL PUMP BODY •...
FUEL TANK • Wipe up any fuel remaining in the recess “a” in Before removing the hose, place a few rags in the fuel pump with a dry rag “1”. the area under where it will be removed. • After installing the fuel hose connector cover “2”, make sure that it is installed securely.
THROTTLE BODY EAS26970 THROTTLE BODY Removing the throttle body 10 Nm (1.0 m kgf, 7.2 ft Ibf) 10 Nm (1.0 m kgf, 7.2 ft Ibf) 1.5 Nm (0.15 m kgf, 1.1 ft Ibf) • • • • • • 10 Nm (1.0 m kgf, 7.2 ft Ibf) 2 Nm (0.2 m...
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THROTTLE BODY Removing the throttle body 10 Nm (1.0 m kgf, 7.2 ft Ibf) 10 Nm (1.0 m kgf, 7.2 ft Ibf) 1.5 Nm (0.15 m kgf, 1.1 ft Ibf) • • • • • • 10 Nm (1.0 m kgf, 7.2 ft Ibf) 2 Nm (0.2 m...
THROTTLE BODY EAS2DM1089 EAS2DM1091 REMOVING THE FUEL HOSE INSTALLING THE FUEL HOSE 1. Disconnect: 1. Install: • Fuel hose • Fuel hose Refer to “REMOVING THE FUEL TANK” on • Fuel hose connector cover page 7-2. ECA2DM1039 NOTICE EAS26980 When installing the fuel hose, make sure that CHECKING THE FUEL INJECTOR it is securely connected, and that the fuel 1.
THROTTLE BODY EAS2DM1093 CHECKING THE THROTTLE POSITION SENSOR 1. Check: • Throttle position sensor Refer to “CHECKING THE THROTTLE PO- SITION SENSOR” on page 8-147. EAS2DM1094 CHECKING THE ISC (IDLE SPEED CONTROL) UNIT 1. Check: • ISC (idle speed control) unit Refer to “CHECKING THE ISC (IDLE SPEED CONTROL) UNIT”...
IGNITION SYSTEM EAS27120 TROUBLESHOOTING The ignition system fails to operate (no spark or intermittent spark). • Before troubleshooting, remove the following part(s): 1. Storage box 2. Leg shield NG → 1. Check the fuses. (Main, ECU, and ignition) Replace the fuse(s). Refer to “CHECKING THE FUS- ES”...
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IGNITION SYSTEM NG → 9. Check the sidestand switch. Refer to “CHECKING THE Replace the sidestand switch. SWITCHES” on page 8-131. OK ↓ NG → 10.Check the lean angle sensor. Refer to “CHECKING THE LEAN Replace the lean angle sensor. ANGLE SENSOR”...
ELECTRIC STARTING SYSTEM EAS2DM1097 STARTING CIRCUIT CUT-OFF SYSTEM OPERATION (for YP125R) If the main switch is set to “ON” (switch circuit is closed), the starter motor can only operate if the fol- lowing conditions are met: • The brake lever is pulled to the handlebar (the brake switch is closed) and the sidestand is up (the sidestand switch is closed).
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ELECTRIC STARTING SYSTEM 1. Battery 2. Main fuse 3. Main switch 4. Ignition fuse 5. Diode 2 6. Starting circuit cut-off relay 7. Sidestand switch 8. Signaling system fuse 9. Front brake light switch 10. Rear brake light switch 11. Start switch 12.
ELECTRIC STARTING SYSTEM EAS2DM1098 STARTING CIRCUIT CUT-OFF SYSTEM OPERATION (for YP125RA) If the main switch is set to “ON” (switch circuit is closed), the starter motor can only operate if the fol- lowing conditions are met: • The brake lever is pulled to the handlebar (the brake switch is closed) and the sidestand is up (the sidestand switch is closed).
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ELECTRIC STARTING SYSTEM 1. Battery 2. Main fuse 3. Main switch 4. Ignition fuse 5. Signaling system fuse 6. Diode 2 7. Starting circuit cut-off relay 1 8. Rear brake light switch 9. Front brake light switch 10. Starting circuit cut-off relay 2 11.
ELECTRIC STARTING SYSTEM EAS27190 TROUBLESHOOTING The starter motor fails to turn. • Before troubleshooting, remove the following part(s): 1. Storage box 2. Meter assembly 3. Leg shield NG → 1. Check the fuses. (Main, ignition, and signaling sys- tem) Replace the fuse(s). Refer to “CHECKING THE FUS- ES”...
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ELECTRIC STARTING SYSTEM NG → 8. Check the diode 2. Refer to “CHECKING THE DI- Replace the diode 2. ODES” on page 8-141. OK ↓ NG → 9. Check the starter relay. Refer to “CHECKING THE RE- Replace the starter relay. LAYS”...
CHARGING SYSTEM EAS27230 TROUBLESHOOTING The battery is not being charged. • Before troubleshooting, remove the following part(s): 1. Storage box 2. Front cowling 3. Bottom cover NG → 1. Check the fuse. (Main) Replace the fuse. Refer to “CHECKING THE FUS- ES”...
LIGHTING SYSTEM EAS27260 TROUBLESHOOTING Any of the following fail to light: headlight, high beam indicator light, taillights, license plate light or aux- iliary lights. • Before troubleshooting, remove the following part(s): 1. Leg shield NG → 1. Check the condition of each bulb and bulb socket.
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LIGHTING SYSTEM NG → 8. Check the entire lighting system wiring. Properly connect or replace the wire har- Refer to “CIRCUIT DIAGRAM” on ness. page 8-19. OK ↓ Replace the ECU, meter assembly or tail/brake light assembly. 8-22...
SIGNALING SYSTEM EAS27290 TROUBLESHOOTING • Any of the following fail to light: turn signal lights, brake lights, warning light or indicator lights. • The horn fails to sound. • The fuel meter fails to operate. • The coolant temperature meter fails to operate. •...
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SIGNALING SYSTEM Checking the signaling system The horn fails to sound. NG → 1. Check the horn switch. The horn switch is faulty. Replace the left Refer to “CHECKING THE handlebar switch. SWITCHES” on page 8-131. OK ↓ NG → 2.
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SIGNALING SYSTEM NG → 3. Check the hazard switch. The hazard switch is faulty. Replace the Refer to “CHECKING THE right handlebar switch. SWITCHES” on page 8-131. OK ↓ NG → 4. Check the turn signal/hazard relay. Refer to “CHECKING THE TURN Replace the turn signal/hazard relay.
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SIGNALING SYSTEM NG → 2. Check the entire signaling system wiring. Refer to “CIRCUIT DIAGRAM (for Properly connect or replace the wire har- YP125R)” on page 8-23 and “CIR- ness. CUIT DIAGRAM (for YP125RA)” on page 8-25. OK ↓ Replace the ECU or meter assembly. The speedometer fails to operate (for YP125R).
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SIGNALING SYSTEM • Between ECU coupler and meter assembly coupler. (yellow/blue–yellow/blue) The tachometer fails to operate. NG → 1. Check the crankshaft position sen- sor. Replace the crankshaft position sen- Refer to “CHECKING THE CRANK- sor/stator assembly. SHAFT POSITION SENSOR” on page 8-143.
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SIGNALING SYSTEM The engine oil change indicator fails to come on. NG → 1. Check the entire signaling system wiring. Refer to “CIRCUIT DIAGRAM (for Properly connect or replace the wire har- YP125R)” on page 8-23 and “CIR- ness. CUIT DIAGRAM (for YP125RA)” on page 8-25.
COOLING SYSTEM EAS27300 COOLING SYSTEM EAS27310 CIRCUIT DIAGRAM 8-33...
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COOLING SYSTEM 5. Main switch 6. ECU fuse 7. Radiator fan motor fuse 9. Ignition fuse 12.Battery 13.Main fuse 17.Frame ground 30.Coolant temperature sensor 35.ECU (engine control unit) 71.Radiator fan motor 72.Radiator fan motor relay 8-34...
COOLING SYSTEM EAS27320 TROUBLESHOOTING • The radiator fan motor fails to turn. • Before troubleshooting, remove the following part(s): 1. Storage box 2. Leg shield NG → 1. Check the fuses. (Main, ignition, ECU, and radiator fan motor) Replace the fuse(s). Refer to “CHECKING THE FUS- ES”...
FUEL INJECTION SYSTEM EAS27350 ECU SELF-DIAGNOSTIC FUNCTION The ECU is equipped with a self-diagnostic function in order to ensure that the fuel injection system is operating normally. If this function detects a malfunction in the system, it immediately operates the en- gine under substitute characteristics and illuminates the engine trouble warning light to alert the rider that a malfunction has occurred in the system.
FUEL INJECTION SYSTEM When an abnormal signal is received from a sensor, the ECU processes the specified values that are programmed for each sensor in order to provide the engine with alternate operating instructions that enable the engine to continue operating or stop operating, depending on the conditions. 3.
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FUEL INJECTION SYSTEM Setting the diagnostic mode 1. Set the main switch to “OFF”. 2. Disconnect the wire harness coupler from the fuel pump. 3. Disconnect the self-diagnosis signal coupler, and then connect the FI diagnostic tool “1” as shown. 4.
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FUEL INJECTION SYSTEM • If a diagnostic code number has a corresponding fault code number, the information is shown in “TROUBLESHOOTING DETAILS”. (Refer to “TROUBLESHOOTING DETAILS” on page 8-45.) • If a diagnostic code number does not have a corresponding fault code number, the information is shown in “DIAGNOSTIC CODE TABLE”.
FUEL INJECTION SYSTEM EAS27462 TROUBLESHOOTING DETAILS This section describes the measures per fault code number displayed on the multi-function meter. Check and service the items or components that are the probable cause of the malfunction following the order given. After the check and service of the malfunctioning part have been completed, reset the multi-function meter according to the “Confirmation of service completion”.
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FUEL INJECTION SYSTEM Fault code No. Crankshaft position sensor: no normal signals are received Item from the crankshaft position sensor. Defective crankshaft posi- Check the crankshaft posi- Crank the engine. tion sensor. tion sensor. Fault code number is not dis- played →...
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FUEL INJECTION SYSTEM Fault code No. Item Intake air pressure sensor: open or short circuit detected. Installed condition of intake Improperly installed sensor Turn the main switch to “ON”. → Reinstall or replace the air pressure sensor. Fault code number is not dis- played →...
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FUEL INJECTION SYSTEM Fault code No. Intake air pressure sensor: hose system malfunction (clogged Item or detached hose). Probable cause of mal- Confirmation of service Item Maintenance job function and check completion Condition of intake air pres- Clogged or detached hose Start the engine and let it idle →...
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FUEL INJECTION SYSTEM Fault code No. Item Throttle position sensor: open or short circuit detected. Probable cause of mal- Confirmation of service Item Maintenance job function and check completion Improperly connected → Connection of throttle posi- Turn the main switch to “ON”. tion sensor coupler.
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FUEL INJECTION SYSTEM Fault code No. Item Throttle position sensor: open or short circuit detected. Defective throttle position Check throttle position sen- Turn the main switch to “ON”. sensor. sor signal. Fault code number is not dis- played → Service is finished. Execute the diagnostic mode.
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FUEL INJECTION SYSTEM Fault code No. Throttle position sensor: stuck throttle position sensor is de- Item tected. Defective throttle position Check throttle position sen- Turn the main switch to “ON” sensor. sor signal. and then open and close the Execute the diagnostic throttle valve.
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FUEL INJECTION SYSTEM Fault code No. Sidestand switch: a break or disconnection of the blue/yellow Item lead of the ECU is detected. Improperly connected → Connection of wire harness Turn the main switch to “ON”, ECU coupler. Connect the coupler secure- and then extend and retract Check the locking condition ly or replace the wire har-...
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FUEL INJECTION SYSTEM Fault code No. Item Coolant temperature sensor: open or short circuit detected. Open or short circuit → Re- Wire harness continuity. Turn the main switch to “ON”. place the wire harness. Fault code number is not dis- played →...
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FUEL INJECTION SYSTEM Fault code No. Item Intake air temperature sensor: open or short circuit detected. Improperly connected → Connection of wire harness Turn the main switch to “ON”. ECU coupler. Connect the coupler secure- Fault code number is not dis- played →...
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FUEL INJECTION SYSTEM Fault code No. sensor: no normal signals are received from the O sensor. Item Able to start engine Fail-safe system Able to drive vehicle Diagnostic code No. — FI diagnostic tool display — Procedure — Probable cause of mal- Confirmation of service Item Maintenance job...
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FUEL INJECTION SYSTEM Fault code No. sensor: no normal signals are received from the O sensor. Item Defective O sensor. Check the O sensor. Start the engine, warm it up, and then race it, or execute Replace if defective. the diagnostic mode. (Code Refer to “ENGINE REMOV- No.
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FUEL INJECTION SYSTEM Fault code No. Ignition coil: open or short circuit detected in the primary lead Item of the ignition coil. Unable to start engine Fail-safe system Unable to drive vehicle Diagnostic code No. Actuates the ignition coil five times at one-second intervals. Actuation Illuminates the engine trouble warning light.
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FUEL INJECTION SYSTEM Fault code No. Component other than ISC (idle speed control) unit is de- fective (ISC operating sound is heard). Item Defective ISC (idle speed control) unit (ISC operating sound is not heard). Able to start engine Fail-safe system Able to drive vehicle Diagnostic code No.
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FUEL INJECTION SYSTEM Fault code No. Component other than ISC (idle speed control) unit is de- fective (ISC operating sound is heard). Item Defective ISC (idle speed control) unit (ISC operating sound is not heard). ISC valve is not moving cor- Replace the throttle body as- Start the engine and let it idle rectly.
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FUEL INJECTION SYSTEM Fault code No. Component other than ISC (idle speed control) unit is defective (ISC operating sound is heard). Item Defective ISC (idle speed control) unit (ISC operating sound is not heard). Improperly connected → Connection of ISC (idle Execute the diagnostic speed control) unit coupler.
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FUEL INJECTION SYSTEM • If fault code numbers “37” and “46” are both indicated, take the actions specified for fault code number “46” first. • If fault code numbers “37” and “42” are both indicated, take the actions specified for fault code number “42”...
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FUEL INJECTION SYSTEM Fault code No. Item Lean angle sensor: open or short circuit detected. Unable to start engine Fail-safe system Unable to drive vehicle Diagnostic code No. Lean angle sensor output voltage FI diagnostic tool display • 0.4–1.4 (upright) •...
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FUEL INJECTION SYSTEM Fault code No. 42 (For YP125R) Speed sensor: no normal signals are received from the speed Item sensor. Diagnostic code No. Front wheel speed pulse FI diagnostic tool display 0–999 Check that the number increases when the front wheel is rotated. Procedure The number is cumulative and does not reset each time the wheel is stopped.
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FUEL INJECTION SYSTEM Fault code No. 42 (For YP125RA) Front wheel sensor: no normal signals are received from the Item front wheel sensor. Able to start engine Fail-safe system Able to drive vehicle Diagnostic code No. Vehicle speed pulse FI diagnostic tool display 0–999 Check that the number increases when the front wheel is rotated.
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FUEL INJECTION SYSTEM Fault code No. 42 (For YP125RA) Front wheel sensor: no normal signals are received from the Item front wheel sensor. Wire harness continuity or Execute the diagnostic Open or short circuit → Re- defective front wheel sensor. mode.
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FUEL INJECTION SYSTEM Fault code No. Fuel system voltage: incorrect voltage supplied to the fuel in- Item jector and fuel pump. Probable cause of mal- Confirmation of service Item Maintenance job function and check completion Improperly connected → Connection of wire harness Start the engine and let it idle ECU coupler.
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FUEL INJECTION SYSTEM Fault code No. EEPROM fault code number: an error is detected while reading Item or writing on EEPROM. “01” is indicated in diagnostic Change the CO concentra- Turn the main switch to “ON”. mode (Code No. D60). EEP- tion, and rewrite in EE- Fault code number is not dis- played →...
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FUEL INJECTION SYSTEM Fault code No. Faulty ECU memory. (When this malfunction is detected in the Item ECU, the fault code number might not appear on the multi- function meter.) Unable to start engine Fail-safe system Unable to drive vehicle Diagnostic code No.
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FUEL INJECTION SYSTEM Fault code No. Item ISC (idle speed control) unit: open or short circuit detected. Open or short circuit → Re- Wire harness continuity. Turn the main switch to “ON”. place the wire harness. Fault code number is not dis- played →...
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FUEL INJECTION SYSTEM Fault code No. Er-1 ECU (engine control unit) internal malfunction (output signal Item error): signals cannot be transmitted between the ECU and the multi-function meter. Open or short circuit → Re- Wire harness continuity. Turn the main switch to “ON”. place the wire harness.
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FUEL INJECTION SYSTEM Fault code No. Er-2 ECU (engine control unit) internal malfunction (output signal Item error): no signals are received from the ECU within the speci- fied duration. Defective meter assembly. Replace the meter assembly. Turn the main switch to “ON”. Fault code number is not dis- played →...
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FUEL INJECTION SYSTEM Fault code No. Er-4 ECU (engine control unit) internal malfunction (input signal er- Item ror): non-registered data has been received from the meter. Able to start engine Fail-safe system Able to drive vehicle Diagnostic code No. — FI diagnostic tool display —...
FUEL PUMP SYSTEM EAS27570 TROUBLESHOOTING If the fuel pump fails to operate. • Before troubleshooting, remove the following part(s): 1. Storage box 2. Leg shield NG → 1. Check the fuses. (Main, ECU, and ignition) Replace the fuse(s). Refer to “CHECKING THE FUS- ES”...
IMMOBILIZER SYSTEM EAS27670 GENERAL INFORMATION This vehicle is equipped with an immobilizer system to help prevent theft by re-registering codes in the standard keys. This system consists of the following: • a code re-registering key (with a red bow) • two standard keys (with a black bow) that can be re-registered with new codes •...
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IMMOBILIZER SYSTEM Parts to be replaced Main switch/immo- Key registration re- Accesso- bilizer unit Standard quirement ry lock* Main Immobiliz- and key switch er unit √ Standard key is lost New standard key All keys have been Code re-registering √ √...
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IMMOBILIZER SYSTEM Standby mode a. Main switch “ON” e. Standby mode on b. Main switch “OFF” f. Standby mode off c. LED on d. LED off Standard key registration: Standard key registration is required when a standard key is lost and needs to be replaced, or when the code re-registering key is re-registered after the immobilizer unit or ECU are replaced.
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IMMOBILIZER SYSTEM Standard key registration a. Main switch “ON” B. Immobilizer system indicator light stops flashing when the registration of the second b. Main switch “OFF” standard key is complete. c. LED on d. LED off e. Less than 5.0 s f.
IMMOBILIZER SYSTEM EAS27700 TROUBLESHOOTING When the main switch is turned to “ON”, the immobilizer system indicator light does not come on nor flashes. NG → 1. Check the fuses. (Main, ignition, ECU, and backup) Replace the fuse(s). Refer to “CHECKING THE FUS- ES”...
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IMMOBILIZER SYSTEM Fault Part Symptom Cause Action code IMMOBILIZER Codes between the 1. Signal received from 1. Place the immo- UNIT key and immobilizer other transponder bilizer unit at unit do not match. (failed to recognize least 50 mm code after ten con- away from the secutive attempts).
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IMMOBILIZER SYSTEM a. Light on b. Light off 8-87...
The following troubleshooting describes the problem identification and service method using the Yamaha diagnostic tool. For information about using the Yamaha diagnostic tool, refer to “[B-2] DIAG- NOSIS USING THE FAULT CODES” on page 8-99. For troubleshooting items other than the following items, follow the normal service method.
Previous malfunctions can be checked since the ABS ECU also stores the mal- function history. The fault codes recorded in the ABS ECU can be checked using the Yamaha diagnostic tool. When the service is finished, check the normal operation of the vehicle, and then delete the fault code(s). For in- formation about deleting the fault codes, refer to “[B-3] DELETING THE FAULT CODES”...
The main fuse is blown. • The meter assembly circuit is • defective. The connection with the Yamaha • [A-3] The ABS warning light comes diagnostic tool is defective. Cannot communicate Return to [A]. The ABS ECU fuse is blown.
EAS2DM1125 [A-3] THE ABS WARNING LIGHT COMES ON Connect the Yamaha diagnostic tool to the ABS test coupler. If the Yamaha diagnostic tool cannot com- municate with the vehicle, perform the following steps. For information about connecting the Yamaha diagnostic tool, refer to “[B-2] DIAGNOSIS USING THE FAULT CODES” on page 8-99.
5. The hydraulic unit assembly is defective. EAS2DM1127 [B-1] MALFUNCTION ARE CURRENTLY DETECTED When the Yamaha diagnostic tool is connected to the ABS test coupler, the fault codes will be displayed on the computer screen. • Fault code number is displayed. [B-2] •...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) When the Yamaha diagnostic tool is connected to the vehicle, the operation of the multi-function meter and indicators will be different from the normal operation. 8-100...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Operation of the Yamaha diagnostic tool (Fault diagnosis mode) Malfunction results are displayed in the top part of the window area. Hydraulic unit assembly Detected Power is not supplied to the ABS motor. Rear wheel sensor Recovered Rear wheel sensor circuit is open or short-circuited.
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The diagnosis codes related to the detected malfunction are displayed. Fault code table The details of the fault codes displayed using the Yamaha diagnostic tool are shown in the following table. Refer to this table when checking the vehicle. Delete the fault codes when the service is finished. [B-3] •...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code Item Symptom Check point Rear wheel sensor (ab- Rear wheel sensor signal • Foreign material ad- normal pulse period) is not received properly. hered around the rear (The pulse period is ab- wheel sensor normal while the vehicle is •...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code Item Symptom Check point Rear wheel sensor (miss- Rear wheel sensor signal • Foreign material ad- ing pulses) is not received properly. hered around the rear (Missing pulses are de- wheel sensor tected in the signal while •...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code Item Symptom Check point Hydraulic unit assembly Power is not supplied to • Blown ABS motor fuse (abnormal ABS motor the motor circuit in the hy- • Defective coupler be- power supply) draulic unit assembly.
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code Item Symptom Check point Rear wheel sensor (miss- Rear wheel sensor signal • Foreign material ad- ing pulses) is not received properly. hered around the rear (Missing pulses are de- wheel sensor tected in the signal while •...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code Item Symptom Check point Hydraulic unit assembly Abnormality is detected in • Defective hydraulic unit (abnormal internal power the power supply circuit in assembly supply) the hydraulic unit assem- bly. Front wheel sensor power Power voltage supplied •...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code No. Item Front wheel sensor (intermittent pulses or no pulses) Front wheel sensor signal is not received properly. (Pulses are Symptom not received or are received intermittently while the vehicle is traveling.) Item/components and probable Order Check or maintenance job...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code No. Item Front wheel sensor (abnormal pulse period) Front wheel sensor signal is not received properly. (The pulse Symptom period is abnormal while the vehicle is traveling.) Item/components and probable Order Check or maintenance job cause Foreign material adhered around the Check the surface of the sensor rotor and wheel...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code No. Item Rear wheel sensor (abnormal pulse period) Rear wheel sensor signal is not received properly. (The pulse Symptom period is abnormal while the vehicle is traveling.) Item/components and probable Order Check or maintenance job cause Defective sensor rotor or incorrect in- Check the surface of the sensor rotor for damage.
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code No. Item Front wheel sensor (open or short circuit) Symptom Open or short circuit is detected in the front wheel sensor. Item/components and probable Order Check or maintenance job cause Open or short circuit in the wire har- •...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code No. Item Rear wheel sensor (open or short circuit) Symptom Open or short circuit is detected in the rear wheel sensor. Item/components and probable Order Check or maintenance job cause Defective coupler between the rear •...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code No. Item Front wheel sensor (missing pulses) Front wheel sensor signal is not received properly. (Missing Symptom pulses are detected in the signal while the vehicle is traveling.) Item/components and probable Order Check or maintenance job cause Foreign material adhered around the...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code No. Item Rear wheel sensor (missing pulses) Rear wheel sensor signal is not received properly. (Missing Symptom pulses are detected in the signal while the vehicle is traveling.) Item/components and probable Order Check or maintenance job cause Defective sensor rotor or incorrect in-...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code No. Item Brake light switch or tail/brake light Brake light signal is not received properly while the vehicle is Symptom traveling (brake light circuit, or front or rear brake light switch circuit). Item/components and probable Order Check or maintenance job...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code No. Hydraulic unit assembly (short circuit in ABS solenoid power Item supply circuit) Short circuit is detected in the solenoid power supply circuit Symptom in the hydraulic unit assembly. Item/components and probable Order Check or maintenance job cause...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code No. Hydraulic unit assembly (short circuit in ABS motor power Item supply circuit) Short circuit is detected in the motor power supply circuit in Symptom the hydraulic unit assembly. Item/components and probable Order Check or maintenance job cause...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code No. Rear wheel ABS (intermittent wheel speed pulses or incorrect Item depressurization) • Pulses from the rear wheel sensor are received intermittently while the vehicle is traveling. (For fault code No. 42) Symptom •...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code No. Item Front wheel sensor (missing pulses) Front wheel sensor signal is not received properly. (Missing Symptom pulses are detected in the signal while the vehicle is traveling.) Item/components and probable Order Check or maintenance job cause Defective sensor rotor or incorrect in-...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code No. • Vehicle system power supply (voltage of ABS ECU power supply is high) (for fault code No. 51) Item • Vehicle system power supply (voltage of wheel sensor power supply is high) (for fault code No. 52) •...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code No. Hydraulic unit assembly (defective ABS solenoid and ABS mo- Item tor power supply circuits) Abnormality is detected in the solenoid or motor power supply Symptom circuit in the hydraulic unit assembly. Item/components and probable Order Check or maintenance job...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code No. Item Hydraulic unit assembly (abnormal internal power supply) Abnormality is detected in the power supply circuit in the hy- Symptom draulic unit assembly. Item/components and probable Order Check or maintenance job cause Defective hydraulic unit assembly Replace the hydraulic unit assembly.
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code No. Front wheel sensor power supply (voltage of power supply is Item low) Power voltage supplied from the ABS ECU to the front wheel Symptom sensor is too low. Item/components and probable Order Check or maintenance job cause...
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ABS (ANTI-LOCK BRAKE SYSTEM) (for YP125RA) Fault code No. Rear wheel sensor power supply (voltage of power supply is Item low) Power voltage supplied from the ABS ECU to the rear wheel Symptom sensor is too low. Item/components and probable Order Check or maintenance job cause...
After the deletion procedure is finished, make sure that all of the fault codes displayed using the Yamaha diagnostic tool have been deleted. Connecting the Yamaha diagnostic tool Remove the protective cap “1”, and then connect the Yamaha diagnostic tool to the ABS test coupler (4P). EAS2DM1130 [C-1] FINAL CHECK Check the vehicle and finish the service according to the following procedures.
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ELECTRICAL COMPONENTS Check each switch for continuity with the pocket tester. If the continuity reading is incorrect, check the wiring connections and, if necessary, replace the switch. ECA14370 NOTICE Never insert the tester probes into the coupler terminal slots “a”. Always insert the probes from the opposite end of the coupler, taking care not to loosen or damage the leads.
ELECTRICAL COMPONENTS EAS27990 EWA37P1018 CHECKING THE BULBS AND BULB WARNING SOCKETS Since headlight bulbs get extremely hot, keep flammable products and your hands Do not check any of the lights that use LEDs. away from them until they have cooled down.
ELECTRICAL COMPONENTS Checking the condition of the bulb sockets 3. Replace: The following procedure applies to all of the bulb • Blown fuse sockets. ▼ ▼▼▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼...
ELECTRICAL COMPONENTS specific gravity of the electrolyte. Therefore, the EAS28030 CHECKING AND CHARGING THE BATTERY charge of the battery has to be checked by mea- EWA13290 suring the voltage at the battery terminals. WARNING Batteries generate explosive hydrogen gas 1. Remove: and contain electrolyte which is made of poi- •...
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ELECTRICAL COMPONENTS • When charging a battery, be sure to remove it from the vehicle. (If charging has to be done with the battery mounted on the vehi- cle, disconnect the negative battery lead from the battery terminal.) • To reduce the chance of sparks, do not plug in the battery charger until the battery charger leads are connected to the battery.
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ELECTRICAL COMPONENTS c. Make sure that the current is higher than the standard charging current written on the bat- Voltage should be measured 30 minutes after tery. the engine is stopped. b. Connect a charger and ammeter to the bat- If the current is lower than the standard charging tery and start charging.
ELECTRICAL COMPONENTS • Upper panel 4. Negative tester probe Refer to “GENERAL CHASSIS” on page 4-1. Result EAS28040 Continuity CHECKING THE RELAYS (between “3” and “4”) Check each switch for continuity with the pocket tester. If the continuity reading is incorrect, re- place the relay.
ELECTRICAL COMPONENTS EAS28050 CHECKING THE DIODES Diode 2 1. Check: • Diode 2 Out of specification → Replace. Br/R Pocket tester 90890-03112 Analog pocket tester b. Turn the main switch to “ON”. YU-03112-C c. Measure the turn signal/hazard relay input voltage.
ELECTRICAL COMPONENTS Refer to “TROUBLESHOOTING” on page 8-3. Minimum ignition spark gap 6.0 mm (0.24 in) If the ignition spark gap is within specification, the ignition system circuit is operating normally. ▼ ▼▼▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼...
ELECTRICAL COMPONENTS • Positive tester probe → yellow (wire harness color) • Negative tester probe → black/blue (wire harness color) e. While slowly opening the throttle, check that the throttle position sensor voltage is in- creased. Voltage does not change or it changes abruptly →...
ELECTRICAL COMPONENTS d. Heat the water or let it cool down to the spec- d. Heat the water or let it cool down to the spec- ified temperature. ified temperatures. e. Measure the intake air temperature sensor e. Measure the air temperature sensor resis- resistance.
ELECTRICAL COMPONENTS EAS37P1085 CHECKING THE ISC (IDLE SPEED CONTROL) UNIT Do not remove the ISC unit completely from the throttle body. 1. Check: • ISC unit ▼ ▼▼▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼...
TROUBLESHOOTING Electrical system EAS28450 TROUBLESHOOTING 1. Battery • Discharged battery EAS28460 • Faulty battery GENERAL INFORMATION 2. Fuse(s) • Blown, damaged or incorrect fuse The following guide for troubleshooting does not • Improperly installed fuse cover all the possible causes of trouble. It should 3.
TROUBLESHOOTING Fuel system • Bent or damaged damper rod 1. Throttle body • Incorrect oil viscosity • Damaged or loose throttle body joint • Incorrect oil level 2. Air filter EAS28670 • Clogged air filter element UNSTABLE HANDLING 1. Handlebar Chassis •...
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TROUBLESHOOTING Headlight bulb burnt out • Wrong headlight bulb • Faulty battery • Faulty rectifier/regulator • Improperly grounded circuit • Faulty main switch • Headlight bulb life expired Tail/brake light does not come on • Wrong tail/brake light LED • Too many electrical accessories •...
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SELF-DIAGNOSTIC FUNCTION AND DIAGNOSTIC CODE TABLE EAS1SD1039 SELF-DIAGNOSTIC FUNCTION AND DIAGNOSTIC CODE TABLE Self-diagnostic function table Fault Reference Item code No. pages Crankshaft position sensor: no normal signals are received from the 8-45 crankshaft position sensor. Intake air pressure sensor: open or short circuit detected. 8-46 Intake air pressure sensor: hose system malfunction (clogged or de- 8-47...
SELF-DIAGNOSTIC FUNCTION AND DIAGNOSTIC CODE TABLE Fault Reference Item code No. pages Immobilizer unit: Key code registration malfunction. 8-85 ECU: Unidentified code is received. 8-85 ISC (idle speed control) unit: open or short circuit detected. 8-68 Communication error with the meter Fault Reference Item...
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SELF-DIAGNOSTIC FUNCTION AND DIAGNOSTIC CODE TABLE Diagnostic Item Meter display Procedure code No. Front wheel speed pulse Front wheel speed pulse Check that the number in- 0–999 creases when the front wheel is rotated. The num- ber is cumulative and does not reset each time the wheel is stopped.
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SELF-DIAGNOSTIC FUNCTION AND DIAGNOSTIC CODE TABLE Diagnostic Item Meter display Procedure code No. Malfunction history code erasure • No history — • History exists • Displays the total num- To erase the history, push ber of malfunctions, in- the start switch “ ”. cluding the current malfunction, that have occurred since the histo-...
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EAS28740 58. Headlight assembly EAS28750 WIRING DIAGRAM COLOR CODE 59. Auxiliary light Black 60. Headlight YP125R 2014 Brown 61. License plate light 1. Crankshaft position sensor Chocolate 62. Meter assembly 2. AC magneto Dark green 63. Multi-function meter 3. Rectifier/regulator Green 64.
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EAS2DM1112 57. Pass switch EAS2DM1113 WIRING DIAGRAM COLOR CODE 58. Turn signal switch Black 59. Horn switch YP125RA 2014 Brown 60. Rear brake light switch 1. Crankshaft position sensor Chocolate 61. Right tail/brake light assembly 2. AC magneto Dark green 62.
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YP125R 2014 YP125R 2014 YP125R 2014 YP125R 2014 YP125R 2014 WIRING DIAGRAM SCHÉMA DE CÂBLAGE SCHALTPLAN SCHEMA ELETTRICO DIAGRAMA ELÉCTRICO Y/G Br/W R/B B/W W/R L/Y L/W L/R Y Gy/G L Lg G/B B/L W/R G/R B/L 19 20 G/YL/W Sb B L B/L W/Y L/Y...
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YP125R 2014 YP125R 2014 YP125R 2014 YP125R 2014 YP125R 2014 WIRING DIAGRAM SCHÉMA DE CÂBLAGE SCHALTPLAN SCHEMA ELETTRICO DIAGRAMA ELÉCTRICO 19 20 OPEN LOCK (Gy)
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YP125RA 2014 YP125RA 2014 YP125RA 2014 YP125RA 2014 YP125RA 2014 WIRING DIAGRAM SCHÉMA DE CÂBLAGE SCHALTPLAN SCHEMA ELETTRICO DIAGRAMA ELÉCTRICO B/L W/R Y/G Br/W R/B B/W W/R L/Y L/W L/R Y Gy/G L Lg G/B Sb B G/R B/L L/B B L B/L R/L O/B B/L P/W L...
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YP125RA 2014 YP125RA 2014 YP125RA 2014 YP125RA 2014 YP125RA 2014 WIRING DIAGRAM SCHÉMA DE CÂBLAGE SCHALTPLAN SCHEMA ELETTRICO DIAGRAMA ELÉCTRICO OPEN LOCK (Gy)