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TDM850 ’96 SERVICE MANUAL: 4TX-AE1 TDM850 ’97 SUPPLEMENTARY SERVICE MANUAL: 4TX-AE2 TDM850 ’99 SUPPLEMENTARY SERVICE MANUAL 1998 by Yamaha Motor Co., Ltd. First Edition, November 1998 All rights reserved. Any reproduction or unauthorized use without the written permission of Yamaha Motor Co., Ltd. is expressly...
EB001000 NOTICE This manual was produced by the Yamaha Motor Company primarily for use by Yamaha dealers and their qualified mechanics. It is not possible to include all the knowledge of a mechanic in one manual, so it is assumed that anyone who uses this book to perform maintenance and repairs on Yamaha motorcycles has a basic understanding of the mechanical ideas and the procedures of motorcycles repair.
EB002000 HOW TO USE THIS MANUAL MANUAL ORGANIZATION This manual consists of chapters for the main categories of subjects. (See “Illustrated symbols”) 1st title 1 : This is the title of the chapter with its symbol in the upper right corner of each page. 2nd title 2 : This title indicates the section of the chapter and only appears on the first page of each section.
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EB003000 ILLUSTRATED SYMBOLS Illustrated symbols 1 to 9 are printed on top SPEC right of each page and indicate the subject of each INFO chapter. General information Specifications INSP Periodic inspection and adjustment Engine Cooling system Carburetion COOL CARB Chassis Electrical Troubleshooting CHAS...
MOTORCYCLE IDENTIFICATION INFO EB100000 GENERAL INFORMATION MOTORCYCLE IDENTIFICATION VEHICLE IDENTIFICATION NUMBER The vehicle identification number 1 is stamped into the right side of the steering head. MODEL LABEL The model label 1 is affixed to the frame. This in- formation will be needed to order spare parts. –1–...
SPEC GENERAL SPECIFICATIONS SPECIFICATIONS GENERAL SPECIFICATIONS Item Standard Model: TDM850 Model code: 4TX4 Basic weight (With oil and full fuel tank): 232 kg Carburetor: Type/quantity BDSR38/2 Manufacturer MIKUNI Transmission Primary reduction system Spur gear Primary reduction ratio 67/39 (1.718) Secondary reduction system Chain drive Secondary reduction ratio 43/16 (2.688)
SPEC MAINTENANCE SPECIFICATIONS MAINTENANCE SPECIFICATIONS ENGINE Item Standard Limit Clutch: Clutch spring free length 50 mm 48 mm Quantity Carburetor: I.D. mark 4TX4 40 Main jet #147.5 Main air jet Jet needle #1: 6DJP17 #2: 6CL1 Needle jet Pilot air jet 1 #87.5 Pilot air jet 2 #120...
SPEC MAINTENANCE SPECIFICATIONS ELECTRICAL Item Standard Limit Charging system: Type A.C. magneto Model/manufacturer TLN252/DENSO Nominal output 14 V 25 A at 5,000 r/min 0.23 X 0.35 Ω at 20_C/W-W Stator coil resistance Starter relay: Model/manufacturer MS5F-421 /JIDECO Amperage rating 180 A 4.2 X 4.6 Ω...
SPEC CABLE ROUTING CABLE ROUTING Throttle cable 1 Ignition coil (left) lead G Align the brake hose white mark to Right handlebar switch lead Ignition coil (right) lead the mark of bracket. Brake hose Negative lead H Fasten the brake hose with a plas- Clutch cable tic band and cut the end of band.
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SPEC CABLE ROUTING L Fasten the meter lead and headlight lead with a plas- P Fasten the wireharness with a plastic band. tic band. Q Fasten the wireharness and ignition coil (left) lead M Fasten the wireharness with a plastic band. with a plastic band.
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SPEC CABLE ROUTING Front flasher light (left) lead A.C. magneto lead A Fasten the left handlebar switch Main switch lead Air filter case breather hose lead and main switch lead with a Starter cable 1 Carburetor heater hose plastic band. Left handlebar switch lead Starter cable 2 B Route the wireharness to the rear-...
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SPEC CABLE ROUTING D Fasten the rear flasher light (left) lead. J Clamp the speed sensor lead to the outer tube with a E Fasten the sidestand switch lead neutral switch lead holder. and A.C. magneto lead. K Clamp the speed sensor lead along the brake hose F Route the sidestand switch lead and air filter case (three position).
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SPEC CABLE ROUTING Battery negative lead Vacuum hose (#1) D Fasten the carburetor air vent hose. Battery positive lead Vacuum hose (#2) E Route the carburetor breather Starter motor lead Coolant reservoir breather hose hoses, vacuum hose (#1) down Fuel sender lead Carburetor breather hose ward and vacuum hose (#2) up- Fuel tank drain hose...
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SPEC CABLE ROUTING J Fasten the right handlebar switch lead and speed S Route the brake switch lead through the guide. sensor lead with a clamp. T Fasten the wireharness, rear flasher lead with a clamp. K Fasten the throttle cable and speed sensor lead with a U Fasten the wireharness with a clamp.
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SPEC CABLE ROUTING Head light lead Fuel tank drain hose A Fasten the meter lead, headlight Wireharness Fuel hose lead wireharness with a clamp. Meter light lead Fuel sender lead B Fasten the wireharness, coolant Throttle cable Starter motor lead reservoir hose with a clamp.
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SPEC CABLE ROUTING H Fasten the carburetor breather hose and see the N To head light. hose mark. O To auxiliary light. I In order to carburetor breather hose, idle adjust cable P To meter. coolant breather hose from downward. Q Fasten the meter lead, headlight lead with a clamp.
INTRODUCTION/ INSP PERIODIC MAINTENANCE/LUBRICATION INTERVALS PERIODIC INSPECTION AND ADJUSTMENT INTRODUCTION This chapter includes all information necessary to perform recommended inspection and adjustments. These preventive maintenance procedures, if followed, will ensure more reliable vehicle operation and a longer service life. The need for costly overhaul work will be greatly reduced. This information applies to vehicles already in service as well as new vehicles that are being prepared for sale.
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Cooling system S Change coolant every 24,000 km or 24 months (whichever comes first). * Since these items require special tools, data and technical skills, they should be serviced by a Yamaha dealer. NOTE: S The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
INSP SEAT, TAIL COVER AND FUEL TANK SEAT, TAIL COVER AND FUEL TANK 16 Nm (1.6mSkg) 3.8 Nm (0.38mSkg) Order Job name/Part name Q’ty Remarks Seat, tail cover and fuel tank removal Remove the parts in the order below. Side cowling Refer to “COWLINGS”.
INSP CARBURETOR SYNCHRONIZATION ENGINE CARBURETOR SYNCHRONIZATION NOTE: Valve clearance and idling speed should be ad- justed properly before synchronizing the carbure- tors. 1. Place the motorcycle on a level surface. NOTE: Place the motorcycle on its centerstand if a cen- terstand is equipped.
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INSP CARBURETOR SYNCHRONIZATION 7. Adjust: S Carburetor synchronization Adjustment steps: S Synchronize carburetor #1 to carburetor #2 by turning synchronizing screw 1 until both gauges read the same. S Race the engine for less than a second, two or three times and check the synchronization again.
INSP ENGINE OIL LEVEL INSPECTION ENGINE OIL LEVEL INSPECTION NOTE: Position the motorcycle straight up when inspect- ing the oil level. 1. Place the motorcycle on a level surface. NOTE: S After idling the engine a few minutes. The summer season is about 5 minutes and the winter season is about 15 minutes.
INSP ENGINE OIL REPLACEMENT ENGINE OIL REPLACEMENT 1. Start the engine and let it warm up for several minutes. 2. Stop the engine and place an oil pan under the drain bolt. 3. Remove: S Oil filler plug 1 4. Remove: S Drain bolt (with gasket) 1 S Oil filter drain bolt (with gasket) 2 Drain the crankcase and oil tank of its oil.
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INSP ENGINE OIL REPLACEMENT 7. Fill: S Crankcase CAUTION: The engine should be filled with oil in two steps. First fill the engine with 3.2 liters of oil. Then start the engine and race it five or six times. Continue idling the engine a few min- utes.
INSP FUEL LINE INSPECTION FUEL LINE INSPECTION 1. Remove: S Side cowling S Seat S Side cover S Fuel tank Refer to “COWLINGS, SEAT, TAIL COVER AND FUEL TANK”. 2. Inspect: S Fuel hoses 1 Cracks /Damage ! Replace. Loose connection ! Connect properly. NOTE: Drain and flush the fuel tank if abrasive damage to any components is evident.
CLUTCH CLUTCH CLUTCH 70 Nm (7.0mSkg) 8 Nm (0.8mSkg) Order Job name/Part name Q’ty Remarks Clutch removal Remove the parts in the order below. Clutch spring Pressure plate Plain washer/Bearing Pull rod Friction plate Friction plate Clutch plate Refer to “REMOVAL”, and Clutch boss nut “INSTALLATION”.
CLUTCH INSTALLATION 1. Install: S friction plates S clutch plates CAUTION: The friction plates are made in two types. The first and last friction plates are different in ma- terial from the other ones and black on the sur- face. Assembly should be done in the correct order.
ELEC INSTRUMENT FUNCTIONS INSTRUMENT FUNCTIONS This combination meter is equipped with the fol- lowing. COMBINATION METER S An odometer S Two trip odometers S A clock Odometer and trip meters Use the trip meters to estimate how far you can Speedometer ride on a tank of fuel.
ELEC SIGNAL SYSTEM EB806010 EB802401 TROUBLESHOOTING 2. Battery S Any of the following fail to light: flasher S Check the condition of the battery. light, trun and fuel level indicator light. Refer to “BATTERY INSPECTION”. S The fuel meter fails to operate. Open-circuit voltage 12.8 V or more at 20_C Check:...
ELEC SIGNAL SYSTEM SIGNAL SYSTEM CHECK 4. Voltage 1. Flasher light and/or turn indicator light does S Connect the pocket tester (DC 20 V) to the not blink. flasher relay coupler. 1. Flasher/turn indicator light bulb and socket Tester (+) lead ! Brown/Red terminal S Check the flasher/turn indicator light bulb and Tester (–) lead ! Frame ground socket for continuity.
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ELEC SIGNAL SYSTEM 2. The fuel level indicator light fails to come on or S Turn the main switch to “ON” or “P”. the fuel meter fails to operator. S Check for voltage (12 V) on the “Brouwn/White” 1. Fuel level indicator light bulb and socket lead at the flasher relay terminal.
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ELEC SIGNAL SYSTEM S Set the main switch to “ON”. S Is the fuel sender OK? S Measure the voltage (12 V). S Is the voltage within specification? Replace fuel sender. This circuit is OK. The wiring circuit from the main switch to the 3.
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ELEC SIGNAL SYSTEM Battery positive terminal ! red Battery negative terminal ! black Tester positive probe ! white Tester negative probe ! black S Set the main switch to “ON”. S Elevate the front wheel and slowly rotate it. S Does the voltage (5V) read cycle 4 times with each, full rotation of the front wheel? Replace the speed sensor.
ELEC FUEL PUMP SYSTEM EB808010 FUEL PUMP CIRCUIT OPERATION The ignitor unit includes the control unit for the fuel pump. Battery Main fuse Main switch Ignition fuse Engine stop switch Ignitor unit Fuel pump relay Fuel pump –33–...
ELEC FUEL PUMP SYSTEM EB808020 EB802401 TROUBLESHOOTING 2. Battery _Check the condition of the battery. The fuel pump fails to operate. Refer to “BATTERY INSPECTION”. Check: Open-circuit voltage 1. main and ignition fuses 12.8 V or more at 20 C 2.
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ELEC FUEL PUMP SYSTEM S Measure the fuel pump resistance. 5. Fuel pump relay S Disconnect the relay unit from the coupler. Fuel pump resistance 4 X 10 Ω at 20_C S Connect the pocket tester (Ω 1) and battery (12 V) to the relay unit ferminals as shown.
ELEC FUEL PUMP SYSTEM EB808410 CHECKING THE FUEL PUMP WARNING Gasoline is extremely flammable and under certain circumstances there can be a danger of an explosion or fire. Be extremely careful and note the following points: _ Stop the engine before refuelling. _ Do not smoke and keep away from open flames, sparks or any other source of fire.