PIAGGIO B 250 Workshop Manual

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WORKSHOP MANUAL

618162

B 125-250

Table of Contents

Summary of Contents for PIAGGIO B 250

Page 1 WORKSHOP MANUAL 618162 B 125-250...
Page 2 Not all versions/models shown in this publication are available in all countries. The availability of single versions should be checked at the official Piaggio sales network. "© Copyright 2007 - PIAGGIO & C. S.p.A. Pontedera. All rights reserved. Reproduction of this publication in whole or in part is prohibited."...
Page 3 WORKSHOP MANUAL B 125-250 This workshop manual has been drawn up by Piaggio & C. Spa to be used by the workshops of Piaggio- Gilera dealers. This manual is addressed to Piaggio service mechanics who are supposed to have a basic knowledge of mechanics principles and of vehicle fixing techniques and procedures.
Page 5 INDEX OF TOPICS CHAR HARACTERISTICS TOOL OOLING MAIN AINTENANCE TROUBL ROUBLESHOOTING ELE SYS LECTRICAL SYSTEM ENG VE NGINE FROM VEHICLE NGINE SUSP USPENSIONS BRAK SYS RAKING SYSTEM COOL SYS OOLING SYSTEM CHAS HASSIS PRE DE DELIVERY TIME...
Page 6 INDEX OF TOPICS CHAR HARACTERISTICS...
Page 7: Safety Rules
Even though the latter contains no asbestos, inhaling dust is harmful. Maintenance rules - Use original PIAGGIO spare parts and lubricants recommended by the Manufacturer. Non-original or non-conforming spares may damage the vehicle. - Use only the appropriate tools designed for this vehicle.
Page 8: Vehicle Identification
B 125-250 Characteristics Vehicle identification VEHICLE IDENTIFICATION (125) Specification Desc./Quantity Chassis prefix (125) ZAPM 28400 ÷ 1001 Engine prefix (125) M284M VEHICLE IDENTIFICATION (250) Specification Desc./Quantity Chassis prefix (250) ZAPM 28500 ÷ 1001 Engine prefix (250) M285M Dimensions and mass WEIGHTS AND DIMENSIONS Specification Desc./Quantity...
Page 9: Electrical System
B 125-250 Characteristics Transmission TRASMISSION Specification Desc./Quantity Transmission With automatic expandable pulley variator with torque server, V belt, self-ventilating automatic centrifugal dry clutch, gear re- duction unit and transmission housing with forced air circulation cooling. Capacities CAPACITIES Specification Desc./Quantity Engine oil (125) ~ 1100 cc Engine oil (250) ~ 1200 cc...
Page 10: Wheels And Tyres
B 125-250 Characteristics Brakes BRAKES Specification Desc./Quantity Front brake Disc brake, diameter 260 mm and floating calliper with twin plungers and hydraulic control (lever on the far right of the han- dlebar) Rear brake Disc brake, diameter 260 mm and calliper with two counteract- ing plungers and hydraulic control (lever on the far left of the handlebar) Wheels and tyres...
Page 11 B 125-250 Characteristics The 2T reed valve has a diaphragm. The unit, indicated by an arrow in the figure, has a cut-off connected to the depression intake on the inlet manifold that cuts the air inlet in deceleration, to avoid explosions in the muffler.
Page 12 B 125-250 Characteristics The working principle of the SAS for Quasar 250 cc Euro 2 engines is entirely similar to the SAS employed on 2-stroke engines. The main differen- ces are the following: Secondary air enters directly into the exhaust duct on the cylinder head, instead of entering through the exhaust pipe as in two-stroke engines.
Page 13 B 125-250 Characteristics Carburettor 125cc Version Kehin KEIHIN CARBURETTOR 125 Specification Desc./Quantity Depression type CVEK30 Printing on the body Device CUT-OFF Not present Max. jet Minimum jet Max. air jet Minimum air jet Minimum mixture set screw initial opening 2 ± ¼ Conical pin Ø...
Page 14 B 125-250 Characteristics Specification Desc./Quantity Starter diffuser jet Starter jet Starter pin diameter Ø 1,78 ~ 40 Ω Starter device resistance Venturi diffuser Ø 29 (30.3x27) Throttle valve Ø 33 Choke maximum cone Ø 48,0 250cc Version Keihin KEIHIN CARBURETTOR 250 Specification Desc./Quantity Depression type...
Page 15: Tightening Torques
B 125-250 Characteristics Tightening Torques STEERING Name Torque in Nm Upper steering ring nut 30 ÷ 36 Steering lower ring nut 10 ÷ 13 then loosen by 90° Handlebar fixing screw (*) 45 ÷ 50 Fixing screws for handlebar control assembly U-bolts 7 ÷...
Page 16: Cylinder Head
B 125-250 Characteristics MUFFLER Name Torque in Nm Screw fixing manifold to muffler 15.5 ÷ 18.5 Muffler heat guard fixing screw 5 - 6 Exhaust fumes inlet screw 22 ÷ 26 Screw fixing muffler support arm to crankcase 33 ÷ 41 Nuts fixing muffler to support arm 27 ÷...
Page 17: Assembly Clearances
B 125-250 Characteristics COOLING Name Torque in Nm Water pump rotor cover 3 ÷ 4 Screws for water pump rotor driving link 3 ÷ 4 Thermostat cover screws 3 ÷ 4 Bleed screw: (°) Apply LOCTITE 242 medium-strength threadlock (*) The two screws must be tightened to the prescribed torque after having done so with the rear wheel axle nut.
Page 18 B 125-250 Characteristics Name Initials Cylinder Piston Play on fitting Cylinder 2nd Oversize 57.397 ÷ 57.404 57.345 ÷ 57.352 0.045 - 0.059 Cylinder 2nd Oversize 57.404 ÷ 57.411 57.352 ÷ 57.359 0.045 - 0.059 Piston 2nd Oversize 57.411 ÷ 57.418 57.359 ÷...
Page 19 B 125-250 Characteristics Name Description Dimensions Initials Quantity Oil scraper ring 57 x 1 0.10 ÷ 0.30 Oil scraper ring 57 x 2.5 0.15 ÷ 0.35 OVERSIZES MOTOR 250 Name Description Dimensions Initials Quantity Compression ring 72 x 1.5 0.15 ÷ 0.30 Oil scraper ring 72 x 1 0.20 ÷...
Page 20 B 125-250 Characteristics Name Description Dimensions Initials Quantity Flywheel-side half-shaft 16.6 +0-0.05 D = 0.20 - 0.50 Connecting rod 18 -0.10 -0.15 D = 0.20 - 0.50 Spacer tool 51.4 +0.05 D = 0.20 - 0.50 Slot packing system Characteristic Compression ratio, 125 models Cr: 11.50 ÷...
Page 21 B 125-250 Characteristics Cr: 11.50 ÷ 13:1 Measurement «A» to be taken, is a value of piston protrusion. It indicates by how much the plane formed by the piston crown protrudes from the plane formed by the upper part of the cylinder. The further the piston protrudes from the cylinder, the thicker the base gasket to be used (to restore the compression ratio) and vice versa.
Page 22 B 125-250 Characteristics N.B. MEASUREMENT "A" TO BE TAKEN IS A VALUE OF PISTON RE-ENTRY, IT INDICATES BY HOW MUCH THE PLANE FORMED BY THE PISTON CROWN FALLS BELOW THE PLANE FORMED BY THE TOP OF THE CYLINDER. THE FURTHER THE PISTON FALLS INSIDE THE CYLINDER, THE LESS THE BASE GASKET IS TO BE APPLIED (TO RECOVER THE COMPRESSION RATIO) AND VICE VERSA.
Page 23 B 125-250 Characteristics Oversizes OVERSIZES Name Description Dimensions Initials Quantity Compression ring 1st 57.2 x 1 0.15 ÷ 0.30 oversize Oil scraper ring 1st 57.2 x 1 0.10 ÷ 0.30 Oversize Oil scraper ring 1st 57.2 x 2.5 0.15 ÷ 0.35 Oversize Compression ring 2nd 57.4 x 1...
Page 24 B 125-250 Characteristics Product Description Specifications AGIP BRAKE 4 Brake fluid FMVSS DOT 4 Synthetic fluid AGIP PERMANENT SPEZIAL coolant Monoethylene glycol-based antifreeze fluid, CUNA NC 956-16 MONTBLANC MOLYBDENUM Grease for driven pulley shaft adjusting Grease with Molybdenum disulphide GREASE ring and movable driven pulley housing AGIP GREASE PV2 Grease for steering bearings and spindle...
Page 25 INDEX OF TOPICS TOOL OOLING...
Page 26 B 125-250 Tooling APPROPRIATE TOOLS Stores code Description 020151Y Air heater 020331Y Digital multimeter 020648Y Single battery charger 001467Y014 Pliers to extract ø 15-mm bearings 020412Y 15 mm guide TOOL - 26...
Page 27 B 125-250 Tooling Stores code Description 020335Y Magnetic support for dial gauge 020565Y Flywheel lock calliper spanner 020439Y 17 mm guide 020359Y 42x47-mm adaptor 020363Y 20 mm guide TOOL - 27...
Page 28 B 125-250 Tooling Stores code Description 020459Y Punch for fitting bearing on steering tube 020458Y Puller for lower bearing on steering tube 005095Y Engine support 008564Y Flywheel extractor 020434Y Oil pressure control fitting 020382Y011 adapter for valve removal tool TOOL - 28...
Page 29 B 125-250 Tooling Stores code Description 020424Y Driven pulley roller casing fitting punch 020431Y Valve oil seal extractor 020193Y Oil pressure gauge 020306Y Punch for assembling valve seal rings 020360Y Adaptor 52 x 55 mm 020364Y 25-mm guide TOOL - 29...
Page 30 B 125-250 Tooling Stores code Description 020375Y Adaptor 28 x 30 mm 020376Y Adaptor handle 020444Y Tool for fitting/ removing the driven pulley clutch 020330Y Stroboscopic light to check timing 001467Y035 Belle for OD 47-mm bearings 020368Y driving pulley lock wrench TOOL - 30...
Page 31 B 125-250 Tooling Stores code Description 020319Y Immobilizer check tester 020287Y Clamp to assemble piston on cylinder 020263Y Sheath for driven pulley fitting 020262Y Crankcase splitting strip 020430Y Pin lock fitting tool 020428Y Piston position check support TOOL - 31...
Page 32 B 125-250 Tooling Stores code Description 020426Y Piston fitting fork 020425Y Punch for flywheel-side oil seal 020423Y driven pulley lock wrench 020414Y 28-mm guide 020393Y Piston fitting band 020382Y Valve cotters equipped with part 012 re- moval tool TOOL - 32...
Page 33 B 125-250 Tooling Stores code Description 020455Y 10-mm guide 020442Y Pulley lock wrench 020440Y Water pump service tool 020329Y MityVac vacuum-operated pump 020357Y Adaptor 32 x 35 mm 020409Y Multimeter adaptor - Peak voltage detec- tion TOOL - 33...
Page 34 B 125-250 Tooling Stores code Description 020456Y Ø 24 mm adaptor 020332Y Digital rev counter 020074Y Support base for checking crankshaft alignment 020055Y Wrench for steering tube ring nut 002465Y Pliers for circlips 001330Y Tool for fitting steering seats TOOL - 34...
Page 35 B 125-250 Tooling Stores code Description 020454Y Tool for fitting piston pin stops (200 - 250) 020622Y Transmission-side oil guard punch 020444Y011 adapter ring 020444Y009 46x55 Wrench 001467Y Extractor for bearings for holes 001467Y013 Pliers to extract ø 15-mm bearings TOOL - 35...
Page 36 B 125-250 Tooling Stores code Description 020444Y010 adapter ring 020244Y 15-mm diameter punch 020115Y Ø 18 punch 020271Y Tool for removing-fitting silent bloc 020627Y Flywheel lock wrench 020467Y Flywheel extractor TOOL - 36...
Page 37 B 125-250 Tooling Stores code Description 020626Y Driving pulley lock wrench 020628Y Water pump service kit TOOL - 37...
Page 38 INDEX OF TOPICS MAIN AINTENANCE...
Page 39: Maintenance Chart
B 125-250 Maintenance Maintenance chart EVERY 3,000 KM Action Engine oil - level check/ top-up VERY YEARS Action Coolant - change Brake fluid - change Secondary air filter (external/internal) - cleaning (125) 1000 K FTER Action Engine oil - replacement Hub oil - change Engine oil - change Idle speed (*) - adjustment...
Page 40 B 125-250 Maintenance Action Coolant level - check Steering - adjustment Brake control levers - greasing Brake pads - check condition and wear Brake fluid level - check Transmission elements - lubrication Safety locks - check Suspensions - check Electrical system and battery - check Headlight - adjustment Tyre pressure and wear - check Vehicle and brake test - road test...
Page 41 B 125-250 Maintenance Action Air filter - clean Variable speed rollers - check or replacement Driving belt - checking Coolant level - check Brake pads - check condition and wear Brake fluid level - check Electrical system and battery - check Tyre pressure and wear - check Vehicle and brake test - road test engine oil- change(125)
Page 42: Checking The Spark Advance
B 125-250 Maintenance Action Suspensions - check Electrical system and battery - check Headlight - adjustment Tyre pressure and wear - check Secondary air filter (250) - Cleaning Vehicle and brake test - road test (*) Vedere norme della sezione «Regolazione del minimo» Carburettor - Disassemble the carburettor in its parts, wash all of them with solvent, dry all body grooves with compressed air to ensure adequate cleaning.
Page 43 B 125-250 Maintenance - Start the engine and check that the light works properly and the rpm indicator can read also the high rpm (e.g. 8000 rpm). - If flash unsteadiness or revolution reading error is detected (e.g. half values), increase the resistive load on the spark plug power line (10 ÷...
Page 44 B 125-250 Maintenance - Using a screwdriver rotate the fan, mounted onto the drive pulley, until the marking on the flywheel is aligned with that stamped on the flywheel cover, as shown in the picture. - Mark the alignment between fan and transmis- sion cover on the transmission side, as shown in the picture.
Page 45 B 125-250 Maintenance VERSION 250 Specification Desc./Quantity Operation threshold First threshold : 9600±50 Second threshold : 9800±50 Reactivation threshold First threshold : 9500±50 Second threshold : 9700±50 Spark elimination First threshold : 1 spark on 7 Second threshold : 2 sparks on 3 MAIN - 45...
Page 46: Spark Plug
B 125-250 Maintenance Spark plug - Put the vehicle on the central stand. - Open the door on the left side of the vehicle by levering in the recess in the lower part of the door after removing the screw. - Disconnect the spark plug HV cable cap.
Page 47 B 125-250 Maintenance - Insert the plug into the hole with the proper incli- nation, screw it in fully by hand and then tighten it with the specially designed spanner. - Push the spark plug cap all the way down onto the spark plug and then proceed to the reassem- bly.
Page 48: Air Filter
B 125-250 Maintenance Replacement -Remove the oil filler cap «A». - Unscrew the oil drainage plug «B » and drain out all the oil. - Screw the drainage plug again and fill the hub with oil. Recommended products AGIP ROTRA 80W-90 rear hub oil SAE 80W/90 Oil that exceeds the requirements of API GL3 specifications Locking torques (N*m)
Page 49: Engine Oil
B 125-250 Maintenance Footrest Engine oil Replacement The engine oil should be replaced after the first 1,000 km, and then every 6,000 km for the 125cc version and 12,000 km for the 250cc version. The engine must be drained through the net filter drain- ing cap «B»...
Page 50: Engine Oil Filter
B 125-250 Maintenance Perform this operation when the engine cold, as described below: 1) Put the vehicle on its central stand on a flat sur- face. 2) Unscrew dipstick "A", dry it with a clean cloth and refit by screwing it completely. 3) Remove the dipstick again and check that the oil level is between the MAX and MIN marks on the dipstick;...
Page 51: Checking The Valve Clearance
B 125-250 Maintenance If the light turns on during braking, at idling speed or while turning a corner, it is necessary to check the oil level and the lubrication system. Checking the ignition timing -Remove the 4 fixing screws and move away from the engine the flywheel cover fitted with a water pump and cooling manifolds.
Page 52: Cooling System
B 125-250 Maintenance Discharge: 0.15 mm (when cold) Cooling system Level check - To check the level, it is necessary to look inside the expansion tank: a mark on the side of the filler indicates MIN and MAX levels. Top-up The fluid level inspection should be carried out every 6,000 km when the motor is cold, following the methods indicated below: Place the scooter on its centre stand and on flat ground.
Page 53: Braking System
B 125-250 Maintenance Braking system Level check The brake fluid tanks for the front and rear brakes are located on the pumps under the handlebar cover. Proceed as follows: - Bring the scooter onto the centre stand and with the handlebar centred; - check the fluid level at the sight glass as shown in the figure.
Page 54: Headlight Adjustment
B 125-250 Maintenance - Remove the tank cap by loosening the two screws, remove the gasket and top up using only the liquid specified without exceeding the maxi- mum level. CAUTION ONLY USE DOT 4-CLASSIFIED BRAKE FLUID. CAUTION AVOID CONTACT OF THE BRAKE FLUID WITH YOUR EYES, SKIN, AND CLOTHING.
Page 55 B 125-250 Maintenance CO check - Remove RHS footrest. - Remove the gas cap on the exhaust pipe. - Using the original washer, install the exhaust gas collection kit as shown in the picture. - Suitably orientate all the components. - Shut the gas outlet terminal of the tool.
Page 56 B 125-250 Maintenance CHECK THAT THE RESULT IS OBTAINED WITH THE VALVE GAS IN CLOSED POSITION. N.B. ALSO CHECK THE CARBURETION ADJUSTMENT IS OB- TAINED WITH THE FLOW SCREW OPEN BETWEEN 2 AND 4 TURNS. N.B. OTHERWISE, CHECK THE FUEL LEVEL ADJUSTMENT IN THE TANK AND THE FUEL CIRCUIT.
Page 57 B 125-250 Maintenance - Remove the two screws shown in the picture. - Remove the filter indicated in the photograph - Check that the gasket is in good conditions - Check the SAS filter housing for dents or defor- mations - Clean the SAS filter carefully.
Page 58 B 125-250 Maintenance - Remove the plastic support and the gasket as shown in the photograph - Check that the SAS valve plastic support is not dented or distorted - Check that the gasket is in good conditions - Carefully clean the inside and outside filters. Re- place them if damaged or abnormally distorted.
Page 59 INDEX OF TOPICS TROUBL ROUBLESHOOTING...
Page 60: Troubleshooting
B 125-250 Troubleshooting Engine Poor performance POOR PERFORMANCE Possible Cause Operation The carburettor is dirty; fuel pump or vacuum valve damaged Remove, wash with solvent and dry with compressed air or re- place Excess of encrustations in the combustion chamber Descale the cylinder, the piston, the head and the valves Incorrect timing or worn timing system elements Time the system again or replace the worn parts...
Page 61 B 125-250 Troubleshooting Possible Cause Operation Air filter blocked or dirty. Dismantle the sponge, wash with water and shampoo, then soak it in a mixture of 50% petrol and 50% of specific oil (Se- lenia Air Filter Oil), then hand dry without squeezing, allow to drip dry and then reassemble.
Page 62 B 125-250 Troubleshooting Possible Cause Operation Cut off device failure Check that the following parts work properly: valve; diaphragm; spring; and that the air calibration elements are clean; check if the sponge filter is clean too Incorrect idle adjustment Adjust using the rpm indicator Pressure too low at the end of compression Check the thermal group seals and replace worn components Faulty spark plug or incorrect ignition advance...
Page 63 B 125-250 Troubleshooting Clutch grabbing or performing inadequately IRREGULAR CLUTCH PERFORMANCE OR SLIPPAGE Possible Cause Operation Faulty clutch Check that there is no grease on the masses. Check that the clutch mass contact surface with the casing is mainly in the centre with equivalent characteristics on the three masses.
Page 64: Noisy Suspension
B 125-250 Troubleshooting Possible Cause Operation the black ground wire is connected to the negative terminal while the red wire is connected to the terminal marked+. Turn signal lights malfunction TURN INDICATOR NOT WORKING Possible Cause Operation Electronic ignition device failure With the key switch set to "ON"...
Page 65 B 125-250 Troubleshooting Suspension oil leakage IL LEAKAGE FROM SUSPENSION Possible Cause Operation Seal fault or breakage Replace the shock absorber Check the condition of wear of the steering covers and the adjustments. TROUBL - 65...
Page 66 INDEX OF TOPICS ELE SYS LECTRICAL SYSTEM...
Page 67 B 125-250 Electrical system Legend: 1. Front left hand-side turn signal light; two (2) bulb lights for each lamp 2. Immobiliser antenna 3. Electronic ignition device with integrated choke and turn signal controls (ECU) 4. Horn button 5. Turn signal switch 6.
Page 68 B 125-250 Electrical system 13. Low fuel warning light 14. Turn signal warning light (LHS) 15. Instrument panel light bulb 16. Headlamp signal light 17. Odometer with warning lights and level gauges with 7 and 2 light bulbs. 18. Headlight 19.
Page 69 B 125-250 Electrical system N = Black BV = White-Green GN = Yellow-black Gr = Grey Rs = Pink R = Red Vi = Purple V = Green VN = Green-Black BN = White-Black BBl = White-Blue GV = Yellow-Green Ar = Orange Az = Light blue GrBl = Grey-Blue...
Page 70 B 125-250 Electrical system Front side INSTALLING THE ELECTRICAL CIRCUIT Specification Desc./Quantity Installing the electrical circuit Front fuse holder Installing the electrical circuit Two relays Installing the electrical circuit Intercom master-box pre-wiring Installing the electrical circuit To seat opening button Installing the electrical circuit Insert in the appropriate hole Installing the electrical circuit...
Page 71 B 125-250 Electrical system INSTALLING THE ELECTRICAL CIRCUIT Specification Desc./Quantity Installing the electrical circuit To antenna Installing the electrical circuit Clamp Installing the electrical circuit Ignition master-box (ECU) Installing the electrical circuit To headlight ELE SYS - 71...
Page 72 B 125-250 Electrical system INSTALLING THE ELECTRICAL CIRCUIT Specification Desc./Quantity Installing the electrical circuit To engine cut-off switch Installing the electrical circuit To instrument panel Installing the electrical circui To headlight switch Installing the electrical circuit To turn signal switch Installing the electrical circuit To horn button Installing the electrical circuit...
Page 73 B 125-250 Electrical system Back side INSTALLING THE ELECTRICAL CIRCUIT Specification Desc./Quantity Installing the electrical circuit Retaining spring Installing the electrical circuit Guide the battery breathing tube through the frame hole, as shown. ELE SYS - 73...
Page 74 B 125-250 Electrical system INSTALLING THE ELECTRICAL CIRCUIT Specification Desc./Quantity Installing the electrical circuit To battery (-) Installing the electrical circuit To the plafoniera Installing the electrical circuit Clamp Installing the electrical circuit To actuator Installing the electrical circuit To license plate light Installing the electrical circuit To taillight Installing the electrical circuit...
Page 75 B 125-250 Electrical system INSTALLING THE ELECTRICAL CIRCUIT Specification Desc./Quantity Installing the electrical circuit To the plafoniera Installing the electrical circuit Choke device diagnostic port Installing the electrical circuit Battery restraining belt Installing the electrical circuit Seat opening actuator ELE SYS - 75...
Page 76 B 125-250 Electrical system INSTALLING THE ELECTRICAL CIRCUIT Specification Desc./Quantity Installing the electrical circuit Secure the metallic clamp on the red binding so that the cable harness remains underneath the frame tube. Installing the electrical circuit To 12V - 180W power outlet underneath the seat installing the electrical circuit The clamp must be placed on the aft hole Installing the electrical circuit...
Page 77 B 125-250 Electrical system INSTALLING THE ELECTRICAL CIRCUIT Specification Desc./Quantity Installing the electrical circuit Starter motor earth cable Installing the electrical circuit Starter motor positive (+) cable Installing the electrical circuit Screw - tighten up to 10 ÷ 13 Nm Installing the electrical circuit Screw - tighten up to 6 ÷...
Page 78 B 125-250 Electrical system Ignition IGNITION Specification Desc./Quantity Pick - up Magneto flywheel Fuse 15A (N° 7) Electronic ignition device Spark plug HV coil Voltage regulator Battery 12V - 10Ah ELE SYS - 78...
Page 79 B 125-250 Electrical system Headlights and automatic starter section HEADLIGHTS AND AUTOMATIC STARTER SECTION Specification Desc./Quantity Electronic ignition device Fuse 10 A (N°6) Battery 12V - 12Ah Fuse 15 A (N°7) Key switch contacts Dipped beam light 12V-55W Light remote control switch Fuse 4 A (N°4) Bulb for upper beams...
Page 80 B 125-250 Electrical system Specification Desc./Quantity High beam warning light bulb 12V - 1,2W Lights switch with high beam flash Automatic starter Fuse 7,5 A (N°3) Number-plate light bulb 12V 5W Two front parking light bulbs 12V - 5W Two (2) taillight bulbs 12V - 5W N°...
Page 81 B 125-250 Electrical system BATTERY RECHARGE AND START-UP Specification Desc./Quantity Electronic ignition device Voltage regulator Magneto flywheel Pick - up Fuse 15 A (N°7) Battery 12V-12Ah Key switch contacts Fuse 4A (N° 2) Front and rear brake light button Brake light bulbs 12V-10W Start up button Diodo...
Page 82 B 125-250 Electrical system Level indicators and enable signals section LEVEL INDICATORS AND ENABLE SIGNALS SECTION Specification Desc./Quantity Electronic ignition device Fuse 4A (N° 5) Fuse 7,5A (N°1) Key switch contacts Fuse 15 A (N°7) Battery 12V-12Ah Radiatore electric fan motor Thermal switch for electric fan Thermistor ELE SYS - 82...
Page 83 B 125-250 Electrical system Specification Desc./Quantity Oil Pressure Warning Light Bulb 12V - 1,2W Motor Oil pressure sensor Reserve Fuel Warning Light Bulb 12V - 1,2W Fuel level sender Fuel gauge Digital clock Coolant temperature gauge Thermal switch We inform you that a new thermal switch has been introduced starting with frame number ZAPM2300003507739 (X9) ZAPM3620000003383 (X8) ZAPM2850000001025 (Beverly), in order to prevent possible malfunctioning of the thermal switch.
Page 84: Turn Signal Lights
B 125-250 Electrical system Turn signal lights DIRECTION INDICATORS, HORN , UTILITIES Specification Desc./Quantity Turn indicator switch Rh turn indicator warning light bul 12V - 1,2W Lh turn indicator warning light bulb 12V - 1,2W Four turn indicator bulbs N°4 12V-10W Electronic ignition device Horn button Horn...
Page 85 B 125-250 Electrical system Specification Desc./Quantity Saddle electrical opening button Saddle opening actuator Plug socket 12 V - 180 W MAX Fuse 15 A (N°8) Battery 12V-12Ah Helmet compartment lighting button Helmet compartment lamp bulb 12V-5W Checks and inspections Immobiliser The electric ignition system is fed with direct cur- rent and is protected by an antitheft immobilizer integrated to the control unit.
Page 86 B 125-250 Electrical system - There is battery voltage between terminal No. 4 (Red/Black) and the ground lead - There is battery voltage between the terminal No. 4 (Red/Black) and terminal No. 8 (Negative) as shown in the figure. - There is battery voltage between the terminals No.
Page 87 B 125-250 Electrical system Sequence and times must be strictly observed or it will be necessary to repeat the procedure from the start. Once the control unit has been programmed, the control unit is inseparably matched with the MAS- TER key transponder. This matching allows programming further service keys in case of loss, replacement, etc.
Page 88 B 125-250 Electrical system 2-FLASH CODE - Example with programmed control unit, no transponder and/or malfunctioning aerial. Ignition disabled-Vehicle immobilised Diagnostic code - 3 flashes If the 3-flash code is detected, check if the failure occurs when the MASTER key in inserted into the key switch.
Page 89 B 125-250 Electrical system The Pick-Up is connected to the control unit by a single cable; then, for the ground circuit, the control unit is connected to the Pick-Up by the chassis and the engine ground lead. To avoid disturbances in the ignition system during start-up, it is very important that the engine-chassis ground connection bonding is efficient.
Page 90 B 125-250 Electrical system HV coil secondary check Disconnect the spark plug cap from the HV cable and measure the resistance between the HV cable terminal and the HV coil negative terminal (see figure). If non-conforming values are measured, replace the HV coil.
Page 91 B 125-250 Electrical system If non-conforming values are measured, replace the control unit. N.B. THE PLASTIC CAP OF THE POSITIVE TERMINAL ON THE HV COIL PRIMARY IS BLACK AND THE NEGATIVE TER- MINAL ONE IS GREEN. Electric characteristic High voltage coil voltage value High voltage coil voltage value: >...
Page 92 B 125-250 Electrical system Recharge system voltage check The recharge system is provided with a three phase alternator with permanent flywheel. The alternator is directly connected to the voltage regulator. In turn, the latter is directly connected to the ground lead and to the battery positive terminal passing through the 15A protection fuse (No.
Page 93 B 125-250 Electrical system If there is no voltage, connect the multimeter's negative terminal to earth and the positive terminal to the white wire on the automatic choke device. With the ignition switch turned onto the «ON» po- sition, check for the presence of battery voltage. If no voltage is detected, check the wiring connected with the ignition switch and the two fuses 15A (no.
Page 94 B 125-250 Electrical system If no voltage is detected, check the wiring, the connections and the integrity of the main 15A fuse; otherwise proceed as follows: - Use a jumper to connect terminals no. 1 (black/blue) and no. 4 (red/black) (see figure) and, operating the turn signal switch, alternating left and right hand-side, ensure that the turn signal lights light up.
Page 95 B 125-250 Electrical system Specification Desc./Quantity Instrument panel bulb Type: ALL GLASS Power: 12V - 2W Quantity: 5 Front turn indicator bulb Type: Spherical Power: 12V - 10W Quantity: 1 RHS + 1 LHS Helmet compartment light bulb Type: CYLINDRIC Power: 12V - 5W Quantity: 1 Rear turn indicator light bulb...
Page 96 B 125-250 Electrical system FUSES B Specification Desc./Quantity Electric stand prewiring, starter relay switch coil, engine N.1 7,5A stop relay coil, engine disabled warning light, oil pres- sure warning light, reserve fuel warning light, coolant temperature warning light Brake light bulb, starter relay switch inhibitor N.1 4A Horn, passing function N.1 7,5A...
Page 97 B 125-250 Electrical system WHILE THE OTHER TWO RED WIRES MARKED (+) MUST BE CONNECTED TO THE TERMINAL MARKED WITH THE +POSITIVE SIGN WARNING WHEN THE BATTERY IS REALLY FLAT (WELL BELOW 12.6V) IT MIGHT OCCUR THAT 5 HOURS OF RECHARGING ARE NOT ENOUGH TO ACHIEVE OPTIMAL PERFORMANCE. GIVEN THESE CONDITIONS IT IS HOWEVER ESSENTIAL NOT TO EXCEED 8 HOURS OF CON- TINUOUS RECHARGING SO AS NOT TO DAMAGE THE BATTERY ITSELF.
Page 98 B 125-250 Electrical system - If the open-circuit voltage is higher or equal to 12.6V, the battery is charged adequately. Slightly shake or tilt the battery to eliminate any air bubbles formed during recharging. - Check the electrolyte levels again, fill them with distilled water up to the upper level line if necessary, clean battery properly, close each single cell cap tightly and install it on the vehicle.
Page 99 INDEX OF TOPICS ENG VE NGINE FROM VEHICLE...
Page 100 B 125-250 Engine from vehicle Exhaust assy. Removal - Undo the two exhaust manifold fixings on the head. - Undo the three screws fixing the muffler to the support arm. - Remove the full muffler unit. To refit, carry out the removal operations in reverse order, observing the prescribed tightening torques. Locking torques (N*m) Nuts fixing muffler to support arm 27 ÷...
Page 101 B 125-250 Engine from vehicle - Detach the inlet and outlet carburettor fuel lines and the cooling circuit hoses (head outlet and ther- mostat inlet). - Detach the spark plug H.T. cable. - Detach the generator wiring from the vehicle's electrical circuit.
Page 102 INDEX OF TOPICS NGINE...
Page 103: Automatic Transmission
B 125-250 Engine Automatic transmission Transmission cover - To remove the transmission cover it is necessary to remove the plastic cover first, by inserting a screwdriver in the slotted holes. Using the clutch bell lock wrench shown in the figure, remove the driven pulley shaft locking nut and washer.
Page 104 B 125-250 Engine Version 125 - Remove the 4 screws and the housing. - Remove the five screws on two different levels as well as the small casing. Removing the driven pulley shaft bearing - Remove the clip from the inside of the cover. - Remove the bearing from the crankcase by means of: Specific tooling...
Page 105 B 125-250 Engine Refitting the driven pulley shaft bearing - Slightly heat the crankcase from the inside so as not to damage the painted surface. - Insert the bearing in its seat. - Refit the seeger ring. CAUTION USE AN APPROPRIATE REST SURFACE TO AVOID DAM- AGING THE COVER PAINT.
Page 106 B 125-250 Engine - Refit the roller with the special screw. - Tighten to the specified torque. - Refit the intake throat with the O-ring, the sump sealing gasket and a the fan housing. Locking torques (N*m) Anti-flapping roller 12 - 16 Plastic roller - Check that the roller does not show signs of wear and that it turns freely.
Page 107: Inspecting The Clutch Drum
B 125-250 Engine Removing the driven pulley - Remove the spacer, the clutch bell and the whole driven pulley unit. N.B. THE UNIT CAN ALSO BE REMOVED WITH THE DRIVING PULLEY MOUNTED. Inspecting the clutch drum - Check that the clutch bell is not worn or damaged. - Measure the clutch bell inside diameter.
Page 108: Removing The Clutch
B 125-250 Engine Characteristic clutch bell inspection: Limit eccentricity. Admissible limit eccentricity: 0.15 mm Removing the clutch Clutch removal (125 cm³ H2O) Fit the driven pulley spring compressor specific tool with medium length pins screwed in position F from the tool internal side. - Insert the adapter ring 8 in the pins.
Page 109 B 125-250 Engine - Use the special 46x55 wrench component No. 9 to remove the nut fixing the clutch in place. - Dismantle the driven pulley components (Clutch and spring with its plastic holder) CAUTION THE TOOL MUST BE FIRMLY FIXED IN THE CLAMP AND THE CENTRAL SCREW MUST BE BROUGHT INTO CON- TACT WITH THE TOOL.
Page 110 B 125-250 Engine Pin retaining collar - Simultaneously turn and pull the collar manually to remove it. N.B. USE TWO SCREWDRIVERS IF YOU HAVE DIFFICULTY. N.B. BE CAREFUL NOT TO PUSH THE SCREW DRIVERS IN TOO FAR TO AVOID DAMAGE THAT COULD ENDANGER THE O-RING SEAL.
Page 111 B 125-250 Engine - Support the pulley properly using the bell as shown in the figure. Specific tooling 001467Y035 Belle for OD 47-mm bearings - Remove the roller bearing using the modular punch. Specific tooling 020376Y Adaptor handle 020456Y Ø 24 mm adaptor 020363Y 20 mm guide Inspecting the driven fixed half-pulley Version 125...
Page 112 B 125-250 Engine Standard diameter: Ø 40.985 mm Wear limit 0.3 mm Inspecting the driven sliding half-pulley 125 - 200 version - Remove the two internal grommets and the two O-rings. - Measure the movable half-pulley bushing inside diameter. Characteristic Movable driven half-pulley max.
Page 113 B 125-250 Engine MOVABLE DRIVEN HALF-PULLEY DIMENSIONS Specification Desc./Quantity Wear limit 0.3 mm standard diameter Diameter 41.000 - 41.035 mm maximum allowable diameter Ø 41.08 mm Refitting the driven half-pulley bearing - Support the pulley bushing adequately from the threaded side using a wooden surface. - Fit a new roller sleeve as in the figure.
Page 114: Refitting The Driven Pulley
B 125-250 Engine Refitting the driven pulley - Insert the new oil guards and O-rings on the mov- able half-pulley. - Lightly grease the O-rings «A» shown in the fig- ure. - Fit the half-pulley over the bushing using the spe- cific tool.
Page 115 B 125-250 Engine - Insert the new oil guards and O-rings on the mov- able half-pulley. - Lightly grease the O-rings «A» shown in the fig- ure. - Fit the half-pulley over the bushing using the ap- propriate tool - Check that the pins are not worn and proceed to refitting them in their slots.
Page 116 B 125-250 Engine Inspecting the clutch spring - Measure the free length of the mobile driven half- pulley spring. Characteristic Standard length (125) 106 mm limit after use (125) 101 mm Standard length (200 - 250) 123 mm Limit after use (200 - 250) 118 mm Refitting the clutch Version 125...
Page 117 B 125-250 Engine - Fully preload the spring. - Apply the clutch lock nut and tighten it to the specified torque using the specific 46x55 spanner. - Loosen the tool clamp and insert the belt accord- ing to its direction of rotation. - Lock the driven pulley again using the specific tool.
Page 118 B 125-250 Engine - Insert the pulley unit with the belt into the tool. - Slightly preload the spring. - Make sure that the clutch is perfectly inserted into the adapter ring before proceeding to tighten the clutch nut. - Place the tool in the clamp with the control screw on the horizontal axis.
Page 119 B 125-250 Engine Refitting the driven pulley - Reassemble the clutch bell and spacer. Drive-belt - Check that the driving belt is not damaged. - Check the width of the belt. Characteristic 125 4T driving belt - minimum width: 21.5 mm 125 4T driving belt - standard width: 22.5 ±...
Page 120: Removing The Driving Pulley
B 125-250 Engine Removing the driving pulley - Turn the crankshaft until the ropes of the pulley are on a horizontal axis - Insert the adaptor sleeve of the appropriate tool in the hole shown in the photograph - Insert the tool in the hollows and apply the reten- tion ring - Bring in the ring's clamping screws while keeping the tool to support the pulley...
Page 121 B 125-250 Engine Driving pulley removal (125) - With the appropriate tool, remove the nut with the built-in Belleville washer, the drive common to the kick-starter version, and the steel washer. - Remove the fixed driving half-pulley. - Remove the steel washer separating from the bushing.
Page 122 B 125-250 Engine Ø 25.95 mm roller (125): Standard Diameter Ø 18.9 ÷ 19.1 mm Roller: Standard Diameter Diameter 20.5 - 20.7 mm roller (125): Minimum diameter allowed Ø 18.5 mm Roller: Minimum diameter permitted Ø 20 mm Refitting the driving pulley - Preassemble the movable half-pulley with the roller contrast plate by putting the rollers in their housings with the larger support surface touching...
Page 123 B 125-250 Engine - Correctly refit the previously removed Bendix back to its position. - Reassemble the parts of the unit (internal lining, fixed half-pulley, external lining, drive and nut), spread Loctite 243 Quick Set threadlock on the thread and tighten the nut to the prescribed torque. - Avoid the half-pulley rotation with the appropriate stop key tool..
Page 124 B 125-250 Engine Refitting the transmission cover - Check the presence of the 2 centring dowels and the correct installation of the sealing gasket for the oil sump on the transmission cover. - Replace the cover tightening the 10 screws at the specified torque.
Page 125 B 125-250 Engine Removing the wheel axle - Remove the wheel axis complete with gear. - Remove the intermediate gear. Removing the hub bearings - Check the state of the bearings being examined (wear, clearance and noisiness). If faults are de- tected, do the following.
Page 126 B 125-250 Engine Removing the wheel axle bearings - Take out the clip on the outside of the gearbox cover. - Support the hub cover and expel the bearing. By means of the appropriate tools, remove the oil guard as in the figure. Specific tooling 020376Y Adaptor handle 020477Y Adaptor 37 mm...
Page 127 B 125-250 Engine Inspecting the hub shaft - Check the three shafts for wear or distortion of the toothed surfaces, the bearing housings, and the oil seal housings. - In case of anomalies, replace the damaged com- ponents. Inspecting the hub cover - Check that the fitting surface is not dented or distorted.
Page 128 B 125-250 Engine Refitting the hub cover bearings For the fitting of the hub box bearings the engine crankcase and the cover must be heated with the special heat gun. - The three 15 mm bearings must be fitted using the appropriate tools.
Page 129 B 125-250 Engine - Refit the driven pulley shaft bearing with a mod- ular punch as shown in the figure. N.B. IF THE BEARING HAS AN ASYMMETRICAL BALL RETAIN- ER, PLACE IT SO THAT THE BALLS ARE VISIBLE FROM THE HUB INNER SIDE. Specific tooling 020376Y Adaptor handle 020359Y 42x47-mm adaptor...
Page 130 B 125-250 Engine Refitting the ub cover - Fit a new gasket together with the centring dow- els. - Seal the gasket of the breather pipe using black silicone sealant. - Fit the gearbox cover, making sure the breather pipe is in the correct position. - Place the 3 shortest screws, identifiable by their different colour, as shown in the figure.
Page 131: Removing The Stator
B 125-250 Engine Removing the hub cover - Remove the clip fixing the hose to the cylinder. - Remove the 10 fixings - Remove the flywheel cover. - Remove the two clamps, the two couplings and empty the cooling system. - Remove the 4 retainers and the flywheel cover Removing the stator - Remove the two pickup screws and the screw...
Page 132 B 125-250 Engine - Remove the electric terminal of the minimum oil pressure switch. - Remove the two Pick-Up screws and the one for the wiring harness bracket as well as the two stator fixing screws shown in the figure. - Remove the stator and its wiring.
Page 133 B 125-250 Engine Refitting the flywheel cover - Place the flywheel with the top dead centre mark aligned with the crankcase. - Place the flywheel cover by aligning the reference marks of the drive and the crankcase cover. - Reassemble the cover on the engine, placing the three connectors in the drive for the water pump.
Page 134 B 125-250 Engine Locking torques (N*m) Flywheel cover screws 11 - 13 Flywheel and starting Removing the starter motor Version 125 - Remove the two screws indicated in the figure. - Take the starter motor out of its seat - Remove the two screws indicated in the figure. - Take the starter motor out of its seat Removing the flywheel magneto - Lock the rotation of the Flywheel with the calliper...
Page 135 B 125-250 Engine - Remove the water pump shaft and crankshaft spline clip - Line up the two holes in the flywheel as shown in the photo - Screw in the guide bushing that is part of the special flywheel stop tool on the flywheel as shown in the photo.
Page 136 B 125-250 Engine - Insert the special flywheel stop tool on the fly- wheel as shown in the photo Specific tooling 020627Y Flywheel lock wrench - Remove the flywheel nut with its washer - Do up the flywheel nut by three or four threads so that the flywheel does not fall accidentally on extraction - Screw the extractor onto the flywheel and extract...
Page 137 B 125-250 Engine - Oil the free wheel "rollers". Refitting the flywheel magneto - Remove the freewheel retaining plate indicated in the photograph - Remove the transmission gear and the freewheel - Insert the free wheel on the flywheel as shown in the photo - Then refit the flywheel with free wheel and trans- mission gear...
Page 138 B 125-250 Engine - Fit the flywheel being careful to insert the key properly. - Lock the flywheel nut to the prescribed torque - Check that the Pick-Up air gap is between 0.34 ÷ 0.76 mm. The air gap cannot be modified when assembling the Pick-Up.
Page 139 B 125-250 Engine Cylinder assy. and timing system Removing the intake manifold - Remove the flywheel cover completely as de- scribed in the flywheel cover section. - Loosen the 3 crews and remove the intake mani- fold. N.B. TAMPERPROOF SCREWS ARE SUPPLIED WITH 125 CC MODELS.
Page 140 B 125-250 Engine - Remove the return spring of the automatic valve lifter unit and the automatic valve lifter unit and its end of stroke washer. - Loosen the central screw on the tensioner first. - Remove the two fixings shown in the figure. - Remove the tensioner with its gasket.
Page 141 B 125-250 Engine - Remove the command sprocket wheel and the timing chain. - Remove the screws indicated in the figure, the spacer bar and the tensioner slider. The chain tensioning pad must be removed from the transmission side. As regards the lower chain guide pad, it may only be removed after the head has been removed.
Page 142: Removing The Cylinder Head
B 125-250 Engine Removing the cylinder head - Remove the spark plug. - Remove the 2 side fixings shown in the figure. - Loosen the 4 head-cylinder fastening nuts in two or three stages and in criss-cross fashion. - Remove the head, the two centring dowels and the gasket.
Page 143 B 125-250 Engine Removing the cylinder - piston assy. - Remove the chain guide pad. - Pull out the cylinder. - Remove the cylinder base gasket. - Remove the two stop rings, the wrist pin and the piston. - Remove the piston seals. CAUTION TO AVOID DAMAGING THE PISTON, SUPPORT IT WHILE REMOVING THE CYLINDER.
Page 144: Inspecting The Small End
B 125-250 Engine Inspecting the small end - Measure the internal diameter of the small end using an internal micrometer. N.B. REPLACE THE CRANKSHAFT IF THE DIAMETER OF THE ROD SMALL END EXCEEDS THE STANDARD DIAMETER OR IT SHOWS SIGNS OF WEAR OR OVERHEATING. Characteristic Rod small end check-up: Maximum diameter 15.030 mm...
Page 145: Inspecting The Piston
B 125-250 Engine Inspecting the wrist pin - Measure the outside diameter of the gudgeon pin. - Calculate the coupling clearance between pin and connecting rod end. Characteristic Pin diameter: Standard clearance 0.015 ÷ 0.029 mm Pin diameter Standard diameter 14.996 - 15.000 mm Inspecting the piston Version 125...
Page 146 B 125-250 Engine 56.945 ÷ 56.973 mm Fitting clearance Top piston ring - standard coupling clearance Top piston ring - maximum clear- 0.025 ÷ 0.07 mm ance allowed after use Middle piston 0.08 mm ring - standard coupling clearance 0.015 - 0.06 mm Middle piston ring - maximum clearance al- lowed after use oil scraper ring - stand-...
Page 147 B 125-250 Engine Diameter of the wrist pin seat on the piston: Standard clearance 0.001 ÷ 0.010 mm piston diameter 71.953 - 71.981 mm Fitting clearance Top piston ring - standard coupling clearance Top piston ring - maximum clear- 0.015 - 0.06 mm ance allowed after use Middle piston 0.07 mm...
Page 148 B 125-250 Engine - Using a bore meter, measure the inner cylinder diameter at three different points according to the directions shown in the figure. - Check that the head coupling surface is not worn or misshapen. - Pistons and cylinders are classified according to diameter.
Page 149 B 125-250 Engine Characteristic Top piston ring Standard opening: 0.15 ÷ 0.30 mm Middle piston ring Standard opening: 0.10 ÷ 0.30 mm scraper ring Standard opening: 0.15 ÷ 0.35 mm ENG - 149...
Page 150: Removing The Piston
B 125-250 Engine Removing the piston - Install piston and wrist pin onto the connecting rod, aligning the piston arrow the arrow facing to- wards the exhaust. - Fit the wrist pin stop ring onto the appropriate tool - With opening in the position indicated on the tool S = left D= right - Place the wrist pin stop ring into position using a...
Page 151 B 125-250 Engine Measurement «A» to be taken, is a value of piston protrusion. It indicates by how much the plane formed by the piston crown protrudes from the plane formed by the upper part of the cylinder. The further the piston protrudes from the cylinder, the thicker the base gasket to be used (to restore the compression ratio) and vice versa.
Page 152 B 125-250 Engine Measurement «A» to be taken, is a value of piston protrusion. It indicates by how much the plane formed by the piston crown protrudes from the plane formed by the upper part of the cylinder. The further the piston protrudes from the cylinder, the thicker the base gasket to be used (to restore the compression ratio) and vice versa.
Page 153 B 125-250 Engine N.B. MEASUREMENT "A" TO BE TAKEN IS A VALUE OF PISTON RE-ENTRY, IT INDICATES BY HOW MUCH THE PLANE FORMED BY THE PISTON CROWN FALLS BELOW THE PLANE FORMED BY THE TOP OF THE CYLINDER. THE FURTHER THE PISTON FALLS INSIDE THE CYLINDER, THE LESS THE BASE GASKET IS TO BE APPLIED (TO RECOVER THE COMPRESSION RATIO) AND VICE VERSA.
Page 154 B 125-250 Engine Refitting the piston rings Fitting the sealing rings - Place the oil scraper spring on the piston. - Refit the oil scraper ring with the join of spring ends on the opposite side from the ring gap and the word 'TOP' towards the crown of the piston.
Page 155: Inspecting The Cylinder Head
B 125-250 Engine Inspecting the cylinder head - Using a trued bar and feeler gauge check that the cylinder head surface is not worn or distorted. Maximum allowable run-out: 0.05 mm - Check that the camshaft and the rocker pin ca- pacities exhibit no wear.
Page 156 B 125-250 Engine Inspecting the timing system components - Check that the guide shoe and the tensioner shoe are not worn out. - Ensure that the camshaft control pulley chain as- sembly and the sprocket wheel are not worn. - If you encounter wear, replace the parts or, if the chain, sprocket wheel and pulley are worn replace the whole assembly.
Page 157 B 125-250 Engine Inspecting the valve housings - Check the width of the imprint on the valve seat«V» wear limit max. 1.6 mm. - Remove any carbon formation from the valve guides. - Measure the inside diameter of each valve guide. - Take the measurement at three different heights in the rocker arm push direction.
Page 158 B 125-250 Engine - Calculate the clearance between valve and valve guide. - Check that there are no signs of wear on the surface of contact with the articulated register terminal. - If the checks above give no failures, you can use the same valves. For best sealing results, it is advisable to grind the valves.
Page 159 B 125-250 Engine Inspecting the springs and half-cones - Check that the upper spring caps and the cotter halves show no signs of abnormal wear. ENG - 159...
Page 160 B 125-250 Engine Refitting the valves - Lubricate the valve guides with engine oil. - Place the valve spring supports on the head. - Using the special punch, fit the four valve seals. - Fit the valves, the springs and the caps. Using the appropriate tool with adapter, compress the springs and insert the cotters in their seats.
Page 161 B 125-250 Engine - Measure the internal diameter of each rocker arm. Check there are no signs of wear on the pad from contact with the cam and on the jointed adjustment plate. Characteristic Internal rocker arm diameter: Standard diame- Diameter 12.000 - 12.011 mm Rocking lever pin diameter: Standard diameter Diameter 11.977 - 11.985 mm...
Page 162 B 125-250 Engine - Refit the lower timing chain sprocket wheel on the crankshaft, with the chamfer facing the insertion side. - Loop the timing chain around the sprocket on the crankshaft. - Fit the chain tensioner slider from the cylinder head side.
Page 163 B 125-250 Engine - Tighten the clamping screw to the prescribed tor- que. - Set the tensioner cursor in the rest position. - Fit the chain tensioner on the cylinder, using a new gasket, and tight the two screws to the pre- scribed torque.
Page 164 B 125-250 Engine - Fit the timing chain guide pad. - Insert the centring dowel between the cylinder head to the cylinder, fit the cylinder head gasket and the cylinder head. - Lubricate the stud bolt threading. - Tighten up the nuts to a pre-torque of 7±1 N·m - Rotate by a 180°...
Page 165 B 125-250 Engine Assemble the lower timing chain sprocket wheel on the crankshaft, with the chamfer facing the in- sertion side. - Loop the timing chain around the sprocket on the crankshaft. - Fit the chain tensioner slider from the cylinder head side.
Page 166 B 125-250 Engine - Insert the pulley on the cam shaft while keeping the reference 4V in correspondence with the ref- erence mark on the head. - Assemble the counterweight with the corre- sponding fixing screw and tighten to the prescribed torque.
Page 167 B 125-250 Engine Spark plug 12 ÷ 14 Refit the cylinder head cover, tightening the 5 screws to the prescribed torque. Make sure the gasket is positioned properly. Remove the flywheel cover completely as already described in the flywheel chapter. - Reassemble the oil pump control, the chain compartment cover, the by-pass and the oil sump as described in the lubrication chapter.
Page 168 B 125-250 Engine Refitting the rocker-arms cover - Refit the cylinder head cover, tightening the 5 clamping screws to the prescribed torque. - Make sure the gasket is positioned properly. Locking torques (N*m) Tappet cover screws 6 - 7 Nm Refitting the intake manifold Fit the intake manifold and do up the three screws.
Page 169 B 125-250 Engine - Remove the flywheel cover together with the water pump, the flywheel and the stator as described in the magneto flywheel chapter. - Remove the oil filter and the oil pressure switch. - Remove the cylinder/piston/head unit as described in the cylinder head timing system chapter. - Remove the two retainers indicated in the figure and the starter motor.
Page 170 B 125-250 Engine Fitting clearance Connecting rod axial clearance 0.20 - 0.50 Check the radial clearance on the connecting rod. Standard clearance: 0.036 ÷ 0.054 mm -Check the surfaces that limit the axial free-play are not scored and measure the width of the crank- shaft between these surfaces, as shown in the diagram.
Page 171 B 125-250 Engine The crankshaft can be reused when the width is within the standard values and the surfaces show no signs of scoring. - Before opening the crankcase, it is advisable to check the axial clearance of the crankshaft. To do this, use a plate and a support with appropriate tool dial gauge.
Page 172 B 125-250 Engine SHAFT ENDS DO NOT INTERFERE WITH THE MAIN BUSH- INGS. FAILURE TO OBSERVE THIS PRECAUTION CAN DAMAGE THE MAIN BUSHINGS. CAUTION KEEP THE CRANKSHAFT IN ONE OF THE TWO HALVES OF THE CRANKCASE WHEN SEPARATING IT. IF YOU FAIL TO DO THIS, THE CRANKSHAFT MIGHT ACCIDENTALLY FALL.
Page 173 B 125-250 Engine Inspecting the crankshaft alignment To install the drive shaft on the support and to measure the misalignment in the 4 points indicated in figure. - Check that the driving shaft cone, the tab seat, the oil seal capacity, the toothed gear and the threaded tangs are in good working order.
Page 174 B 125-250 Engine Inspecting the crankcase halves - Before proceeding to check the crankcase halves, thoroughly clean all surfaces and oil ducts. - On the transmission-side crankcase half, take particular care when handling the oil pump com- partment and the oil ducts, the by-pass duct, the main bushings and the cooling jet on the trans- mission side (see diagram).
Page 175 B 125-250 Engine THE HEAD LUBRICATION CHANNEL IS PROVIDED WITH A SHUTTER JET; THIS GIVES A "LOW PRESSURE" HEAD LUBRICATION; THIS CHOICE WAS MADE TO REDUCE THE OIL TEMPERATURE IN THE SUMP. THE JET CLOG- GING IMPAIRS THE HEAD LUBRICATION AND THE TIM- ING MECHANISMS.
Page 176 B 125-250 Engine - The bushing housings in the crankcase are avail- able in two categories, Cat. 1 and Cat. 2, as are the crankshafts. - The main bushings are available in three thick- ness categories, identified by colour markings, as shown in the table below.
Page 177 B 125-250 Engine LIEVED TO ALLOW BENDING DURING THE DRIVING OPERATION. N.B. CRANKCASES FOR REPLACEMENTS ARE SELECTED WITH CRANKCASE HALVES OF THE SAME CATEGORY AND ARE FITTED WITH CATEGORY B BUSHINGS (BLUE) Characteristic Standard driving depth 1.35 ÷ 1.6 Diameter of crankcase without bushing 32.953 ÷...
Page 178 B 125-250 Engine Lubrication Conceptual diagrams LUBRICATION CIRCUIT ENG - 178...
Page 179 B 125-250 Engine ENG - 179...
Page 180: Oil Pressure Check
B 125-250 Engine Oil pressure check - After removing the flywheel cover as described in the "Flywheel" chapter, remove the electric con- nexion of the minimum oil pressure switch and then remove the switch. - With the engine idling at 1650 rpm and the oil temperature at ~90°C, check that the oil pressure is between 0.5 ÷...
Page 181 B 125-250 Engine Crankshaft oil seals Removal - First remove the transmission cover and the com- plete driving pulley - Install the base of the appropriate tool on the oil guard using the screws provided. Specific tooling 020622Y Transmission-side oil guard punch - Screw the threaded bar onto the base of the tool and extract the oil guard.
Page 182 B 125-250 Engine - Orientate the oil seal by inserting the bracket which is part of the specific tool. - Tighten the threaded bar onto the crankshaft as far as it will go. - Use the nut to move the base of the tool until you can feel the end of the oil seal driving stroke.
Page 183: Oil Pump
B 125-250 Engine For 125 models, fit a new oil seal on the flywheel side using the specific tool as shown in the photo- graph N.B. FAILURE TO USE THE SPECIFIC TOOL CAN RESULT IN AN INCORRECT DEPTH POSITION AND AS A CONSE- QUENCE IN INADEQUATE OIL SEALING.
Page 184 B 125-250 Engine - Remove the oil pump by undoing the two screws in the figure. - Remove the oil pump seal. N.B. IT IS ADVISABLE TO MARK THE CHAIN IN ORDER TO EN- SURE THAT THE INITIAL DIRECTION OF ROTATION IS MAINTAINED.
Page 185 B 125-250 Engine Refitting - Check there are no signs of wear on the oil pump shaft or body. - Check there are no signs of scoring or wear on the oil pump cover. - If you detect non-conforming measurements or scoring, replace the faulty parts or the unit.
Page 186 B 125-250 Engine Removing the oil sump - Remove the oil filler plug, the transmission cover, the complete driving pulley assembly with belt and the sprocket wheel, as described in the "Trans- mission" chapter. - Drain the oil as described previously. - Remove the seven screws, shown in the dia- gram, and the two rear brake fluid pipe fixing brackets.
Page 187 B 125-250 Engine Refitting the oil sump - Refit the by-pass valve plunger in its housing. - Insert the pressure-regulating spring. - Fit a new sump seal. - Refit the two centring dowels. - Refit the sump, taking care to locate the spring in the appropriate recess machined into the inside of the sump.
Page 188 B 125-250 Engine - Switch the pump to pressure mode (PRES- SURE). - Operate the pump slowly and check if there is an increase of pressure. A small leakage is consid- ered to be normal. If anomalies are detected, replace the pump. N.B.
Page 189: Fuel Supply
B 125-250 Engine the valve opens and the depression is suddenly set to zero. Lack of tightness or the fact that the valve opens at different vacuum values should be regarded as anomalies. In this case, replace it. N.B. LACK OF TIGHTNESS IN THE CUT-OFF VALVE RESULTS IN EXHAUST NOISE (EXPLOSIONS IN THE MUFFLER).
Page 190 B 125-250 Engine - Remove the protection, the bracket and the start- er acting on the screw shown in the figure. - Remove the 2 screws and the starter support with the gasket. - Remove the clamp and cover with the airing filter of the diaphragm chamber.
Page 191 B 125-250 Engine - Remove the vacuum valve together with the di- aphragm. - Unscrew the bayonet joint 1/8 of a turn and re- move, take out the spring and vacuum valve nee- - Remove the 4 screws indicated in the figure. ENG - 191...
Page 192 B 125-250 Engine - Remove the chamber with the accelerating pump, its control and gasket. - Remove the oil pump seal. - Remove the intake and outlet valves of the intake pump from the tank N.B. CAUTION, THE ACCELERATION PUMP VALVES ARE MADE UP OF NOZZLES, SPRING AND BALL.
Page 193 B 125-250 Engine -Remove the maximum nozzle. -Remove diffuser. ENG - 193...
Page 194 B 125-250 Engine - Remove the sprayer. N.B. WHEN CLEANING THE CARBURETTOR BODY REMOVE THE SPRAYER TO AVOID LOSING PARTS. IF THE SPRAY- ER IS FORCED IN ITS HOUSING DO NOT ATTEMPT TO REMOVE IT AS THIS WILL ONLY DAMAGE IT. -Remove the minimum nozzle.
Page 195 B 125-250 Engine Walbro To detach the carburettor from the engine, it is necessary to move the air filter and remove the transmission throttle control, the automatic starter connexion, the clamps anchoring the carburettor to the filter housing and to the inlet manifold, the air delivery pipe to the diaphragm, and the intake fitting.
Page 196 B 125-250 Engine Remove the 4 fixing screws indicated in the figure and the vacuum chamber cover. N.B. DURING THE REMOVAL OF THE COVER TAKE SPECIAL CARE NOT TO RELEASE THE SPRING ACCIDENTALLY. Remove the vacuum valve together with the dia- phragm.
Page 197 B 125-250 Engine Unscrew the bayonet joint 1/8 of a turn, remove it, take out the spring and vacuum valve plunger Remove the 4 screws shown in the figure. Remove the tank with the intake pump, its control and gasket. ENG - 197...
Page 198 B 125-250 Engine Remove the acceleration pump piston with the ring nut, the hood, the O-Ring and the spring from the tank as shown in the figure. Adequately support the carburettor and using a rod and hammer remove the float pin acting from the throttle control side.
Page 199 B 125-250 Engine Remove the cover of the duct from the carburettor to the starter nozzle as shown in the figure. -Remove the maximum nozzle. -Remove diffuser. Remove the sprayer. N.B. THIS OPERATION IS NECESSARY TO AVOID LOSING SPRAYER PARTS WHEN CLEANING THE CARBURETTOR BODY.
Page 200 B 125-250 Engine Remove the minimum flow screw with the O-ring, the washer and the spring. -Remove the 2 fixing screws, the cover, the spring, and the cut-off device diaphragm. CAUTION DO NOT ATTEMPT REMOVING PARTS EMBEDDED IN THE CARBURETTOR BODY SUCH AS: FUEL SUPPLY PIPE, PLUNGER HOUSING, STARTER NOZZLE, PIT COVER FOR PROGRESSIONS AND INLET NOZZLE, MINIMUM AND MAXIMUM AIR GAUGE, THROTTLE VALVE CONTROL...
Page 201 B 125-250 Engine Kehin - Before refitting, wash the carburettor body accu- rately with petrol and compressed air. - Pay special attention to the fuel supply pipe and the plunger seat. - For maximum circuit, check the air adjustment is correct as shown in the figure.
Page 202 B 125-250 Engine - Check that the coupling surfaces, the tank and the diaphragm are not dented. -Check that the depression valve housing pipe is not scratched. - Check that the throttle valve and the shaft do not show abnormal wear. - Check that the plunger seat does not show abnormal wear.
Page 203 B 125-250 Engine - Introduce the float with the rod on the fuel feeding tube side. N.B. INTRODUCE THE RETURN SPRING ON THE FLOAT PLATE ADEQUATELY - Remove the drainage screw from the tank, wash and blow it properly and make sure the accelera- tion pump pipes are clean.
Page 204 B 125-250 Engine - The screw final position should be determined by an exhaust fume analysis. - Adjust the carburettor by turning the screw twice from the close position. Walbro - Before refitting, wash the carburettor body accu- rately with petrol and compressed air. - Pay special attention to the fuel supply pipe and the plunger seat.
Page 205 B 125-250 Engine - For the starter circuit, blow the connection pipe properly with the jet.This is necessary because the nozzle support hides other inaccessible internal calibrations. - Blow the intake nozzle properly. N.B. THE ACCELERATION NOZZLE OUTLET IS EXTREMELY SMALL AND IS ORIENTED TO THE THROTTLE VALVE.
Page 206 B 125-250 Engine Level check Kehin - Place the carburettor inclined as shown in the figure. - Check that the float reference is parallel to the tank coupling surface - If different positions are detected, change the plunger control metal plate direction to obtain the position described above.
Page 207 B 125-250 Engine - Remove the drainage screw from the tank, wash and blow the tank properly and make sure the ac- celeration pump intake and supply valve are clean. - Being the valves unidirectional, blow them care- fully with compressed air, at the inner side of the tank for the intake valve and at the pump piston housing for the supply valve.
Page 208 B 125-250 Engine - Prepare the carburettor for adjustment by rotating the screw 3 turns from the close position. - Check that the rocking lever control of the accel- erating pump does not show abnormal wear. - Check that the end of stroke screw of the rocking lever protrudes 3.2 mm.
Page 209 B 125-250 Engine N.B. THE VALVE CAN BE INSERTED IN ONLY ONE POSSIBLE POSITION. - Reassemble the spring with the pin lock. - Remove the cover of the vacuum chamber being careful to correctly insert the spring in its place on the cover.
Page 210 B 125-250 Engine - Reassemble the filter with its clamp. - Wash and blow dry the starter support. Assemble a new gasket on the carburettor body and tighten the 2 fixing screws. Walbro - Check that the pin does not show signs of wear and that the lock is in the 3rd of the 3 notches.
Page 211 B 125-250 Engine - Check that the diaphragm is not worn or has hardened. If it does, replace it. - Refit the tapered pin on the vacuum valve. - Make sure the spring is in the correct position on the plunger and inserted in its housing. - Assemble the coupling by rotating it 1/8 of a turn.
Page 212 B 125-250 Engine Inspecting the automatic choke device - Check that the piston of the automatic starter is not deformed or rusty. - Check that the piston slides freely from the seat to the support. - Check that the sealing gasket of the piston is not deformed.
Page 213 B 125-250 Engine 5 min Electric characteristic Check the automatic starter: Resistance around 30 Ω Kehin - Check that the automatic starter piston is not de- formed or rusty. - Check that the piston slides freely from the seat to the support. - Check that the piston sealing gasket is not de- formed.
Page 214 B 125-250 Engine TO CARRY OUT THIS CHECK PAY SPECIAL ATTENTION NOT TO GENERATE SHORT CIRCUITS USE A CABLE SECTION WITH A TERMINAL SUITABLE TO BE CONNEC- TED TO THE STARTER. Characteristic Check the automatic starter: Kehin: Protrusion value XX ÷ XX mm at approx. 20°C Check the automatic starter: Kehin maximum protrusion XXX ÷...
Page 215 B 125-250 Engine Characteristic Check the auto starter: Protrusion Value for Walbro 12.5 ÷ 13 mm at approx. 20°C Check the automatic starter: Walbro maximum protrusion 18.5 ÷ 19 mm Check the automatic starter: Walbro max. time 5 min Electric characteristic Walbro Resistance approx.
Page 216 INDEX OF TOPICS SUSP USPENSIONS...
Page 217: Removing The Front Wheel
B 125-250 Suspensions Front Removing the front wheel - Remove the front calliper. - Loosen the wheel axle lock-nut. - Loosen the two wheel axle safety screws on the fork leg, on the brake calliper side. - Pull out the wheel axle. See also Removal Front wheel hub overhaul...
Page 218 B 125-250 Suspensions * Either tool can be used. - Support the front wheel with two wooden shims that make it possible to avoid scratching in the case of contact with the rim. - Insert the punch (consisting of adaptor handle, 15 mm adaptor and guide) from the odometer drive side to permit the removal of the brake disc side bearing and the spacer bushing.
Page 219 B 125-250 Suspensions - Reinsert the spacer bushing on the brake disc side using the appropriate tool and take it to the stop. Specific tooling 020376Y Adaptor handle 020359Y 42x47-mm adaptor 020412Y 15 mm guide 020201Y Spacer bushing driving tube - Turn over the wheel and insert the internal spacer with the part fitted with the Seeger ring facing the bearing on the brake disc side installed previously.
Page 220 B 125-250 Suspensions - Refit the cap and tighten the five fixing screws. Refitting the front wheel - Grease the wheel axle, then install it from the tone wheel side and install the tone wheel proper- - Tighten the wheel axle nut to the prescribed tor- que.
Page 221: Front Fork
B 125-250 Suspensions Removal - Remove the rear handlebar cover. - Remove the pin mounting the handlebar to the steering tube. - Remove the handlebar and place it on the rear cover of the front shield. See also Rear handlebar cover Refitting - Install the handlebars on the steering tube, paying attention to the centring, aligning the recess on the handlebar with that on the steering tube as shown in the figure.
Page 222 B 125-250 Suspensions Removal - Remove the front wheel. - Remove the handlebar. - Using the appropriate tool, loosen and remove the upper ring nut, the distancing washer, the counter ring nut and the spacer ring. - Extract the fork. N.B.
Page 223 B 125-250 Suspensions - Insert the retaining band of the two half-rings. - Using a 19 mm hexagonal spanner, extract the roller bearing. Specific tooling 020458Y Puller for lower bearing on steering tube - Insert the a new plate and a new dust guard in the steering tube - Insert a new roller bearing in the roller tube.
Page 224 B 125-250 Suspensions - Loosen the stem support clamp and remove fork leg and stem. - Remove the first spring featuring 15 turns. - Remove the spring support plate. - Remove the second spring featuring 21 turns. - Drain the oil. - Separate the stem from the leg by removing the screws with copper washer shown in the figure.
Page 225 B 125-250 Suspensions - Keeping the tie rod in vertical position, insert the bell for the Ø 35 mm stems. - Insert the nut in the thread and take out the oil guard Specific tooling 020487Y Fork oil seal extractor - Check the length of the springs.
Page 226 B 125-250 Suspensions - Insert a new oil guard with the special adaptor handle and take it to the stop. - Insert the safety clip. - Insert a new dust guard. - Insert the contrast spring into the pumping mem- ber.
Page 227 B 125-250 Suspensions - Insert the stem into the fork clamp. - Do up the clamp once to allow the stem closure upper cap to be tightened. - Check that the sealing ring on the cap is in good working order, then tighten the cap on the stem to the prescribed torque.
Page 228 B 125-250 Suspensions Specific tooling 020055Y Wrench for steering tube ring nut Locking torques (N*m) Steering lower ring nut 10 ÷ 13 then loosen by 90° Upper steering ring nut 30 ÷ 36 Steering bearing Removal - Remove the fork - Check that the upper ball bearing and the seat of the lower roller bearings do not show signs of wear or pricking.
Page 229: Removing The Rear Wheel
B 125-250 Suspensions - Using two 24 mm wrenches, tighten the screw until the seat and the bearing are fully set in place. N.B. ALWAYS USE A NEW BEARING AND A NEW SEAT. Specific tooling 001330Y Tool for fitting steering seats Rear Removing the rear wheel - Remove the muffler support bracket...
Page 230 B 125-250 Suspensions - Loosen the nut and lock nut on the left-hand side of the scooter (see figure) and unscrew the spindle from the opposite side. - Remove the retaining screw of the rear brake pipe shown in the figure. - Loosen the nut on the inside of the frame from the left-hand side (see figure) and remove the rel- evant spindle;...
Page 231 B 125-250 Suspensions - Install a new silent bloc, making sure it aligns properly with the reference tooth. - Fit the silent blocs, making sure the chamfered part of the silent bloc matches the chamfered part of the bracket - Using the appropriate tool, fit the silent bloc as shown in the photo Specific tooling 020271Y Tool for removing-fitting silent bloc...
Page 232 B 125-250 Suspensions - In order to check the clearance of the swinging arm on the frame side, prepare a retainer using the fixing pin of the swinging arm on the frame and two rings from the special tool 020229Y. Alternatively, use two washers with inside diame- ter of 12 mm for pins, outside diameter min.
Page 233 B 125-250 Suspensions - Using an appropriate tool plant new roller cas- ings, being careful to position the bearings with the O-rings facing outwards Specific tooling 020115Y Ø 18 punch 020244Y 15-mm diameter punch SWINGING ARM SERVICE Specification Desc./Quantity Length of the internal swinging arm spacer on the frame side 228 -0.2/-0.4 mm Length of the internal swinging arm spacer on the engine side 183 0/-0.2 mm...
Page 234 B 125-250 Suspensions 5. Screw on and tighten part 5 to the prescribed torque 6. Tighten part 1 to the prescribed torque Insert the swinging arm - engine bolt and tighten to the prescribed torque SWINGING ARM FITTING Name Torque in Nm Part 1 64 ÷...
Page 235: Shock Absorbers
B 125-250 Suspensions Shock absorbers Removal Proceed as follows: - place the scooter on its centre stand; - lift the engine a little with a jack so as to free the two shock absorbers; - remove the muffler - undo the shock absorber spring assembly clamp- ing screw from the support fixed to the engine on the one side and from that fixed to the muffler on the other;...
Page 236 B 125-250 Suspensions Removal - Loosen and remove the lower retaining bolt of the right-hand shock absorber at the support arm. - Loosen the 2 retaining screws between arm and engine. - Remove the split pin and safety cover; unscrew the wheel axle nut;...
Page 237 B 125-250 Suspensions - Heat the bearing seat using the heat gun - Using the special punch, install a new bearing in the seat as shown in the photograph Specific tooling 020376Y Adaptor handle 020151Y Air heater Refitting To refit, carry out the removal operations in reverse order, observing the prescribed tightening torques. Locking torques (N*m) Rear wheel axle nut 104 ÷...
Page 238: Side Stand
B 125-250 Suspensions Recommended products AGIP GREASE PV2 Grease for control levers on the engine White anhydrous-calcium based grease to protect roller bearings; temperature range between -20 ° C and +120 °C; NLGI 2; ISO-L-XBCIB2 Locking torques (N*m) stand retaining bolt 20 ÷...
Page 239 INDEX OF TOPICS BRAK SYS RAKING SYSTEM...
Page 240: Rear Brake Calliper
B 125-250 Braking system Interventions rules WARNING BRAKING SYSTEM FLUID IS CORROSIVE: ALWAYS WEAR PROTECTIVE GLOVES. IN THE EVENT OF ACCIDENTAL CONTACT WITH YOUR EYES, RINSE THE CONTACT AREA WELL WITH ABUNDANT WATER. THE BRAKE FLUID DRAINED FROM THE SYSTEM IS HARMFUL TO THE ENVIRONMENT. COL- LECTION AND DISPOSAL MUST BE CARRIED OUT IN COMPLIANCE WITH THE REGULATIONS IN FORCE.
Page 241 B 125-250 Braking system Refitting - Fix the brake calliper support plate to the crank- case and the brake calliper to the bracket, tight- ening the screws to the prescribed torque. - Apply the recommended product to the fixing screws of the brake calliper to the bracket. - Purge the system.
Page 242 B 125-250 Braking system Overhaul Proceed as follows: 1) remove the two male hexagonal screws (1) and take out the two pads (10); 2) remove the two male hexagonal screws (2) and remove the reaction plate (3); 3) take out the fixed plate (4) from the guide; 4) remove the internal elements from the floating body (5) with the help of short blows of com- pressed air through the brake fluid pipe in order to...
Page 243 B 125-250 Braking system The body and the reaction plate body work inte- grally and can move axially with respect of the fixed plate that is integral to the strut. The pistons, forced by pressure to push the pad to the disk, cause the reaction plate to push in turn the other pad towards the disc.
Page 244 B 125-250 Braking system Removal - Remove the rear wheel. - Remove the hub and the brake disc. - Carry out the same procedure with the front brake disc. See also Removing the rear wheel Refitting - For the installation, position the disc correctly using the arrow stamped on it as reference. - Tighten the screws to the prescribed torque and apply the recommended product.
Page 245: Front Brake Disc
B 125-250 Braking system - Remove the wheel and check using the appro- priate tools that the axial run-out of the brake surface is within the prescribed limits. - If this is not the case, replace the disc and repeat the test.
Page 246: Front Brake Pads
B 125-250 Braking system Disc Inspection Checking the disc is important; it must be perfectly clean, with no sign of rust, oil or grease or any oth- er dirt, and must show no signs of deep scoring. Characteristic Thickness of a new front disc 4.0 mm Disc thickness at wear limit (front) 3.5 mm...
Page 247 B 125-250 Braking system Refitting To fit, proceed as follows: - Insert the two pads in the callipers. - Screw the two pad lock pins to the correct torque, and apply the recommended product. - Fit the calliper on its support, tightening the two screws to the prescribed torque. N.B.
Page 248 B 125-250 Braking system Pad fastening pin 19.6 ÷ 24.5 Screw tightening calliper to the support 20 ÷ 25 Fixing screws for the calliper support on the engine 20 ÷ 25 Fill Rear - combined Proceed as follows: - Position the vehicle on a flat surface and on the stand - Loosen the two screws shown in the figure and open the front brake fluid reservoir.
Page 249 B 125-250 Braking system 020329Y MityVac vacuum-operated pump Locking torques (N*m) Oil bleed screw 12 - 16 Front Proceed as follows: - Position the vehicle on a flat surface and on the stand - Loosen the two screws shown in the figure and open the front brake fluid reservoir.
Page 250 B 125-250 Braking system Locking torques (N*m) Oil bleed screw 12 - 16 Front brake pump Removal - Remove the rear handlebar cover. - Drain the brake system. - Disconnect the brake fluid line from the pump, paying attention to a possible escape of remaining brake fluid.
Page 251 B 125-250 Braking system 7. Gasket 8. Spring 9. Tank CAUTION ALL THE SEALS AND GASKETS MUST BE REPLACED EVERY TIME THE PUMP IS SERVICED. Refitting - Upon refitting, perform the operation but in reverse order. - Tighten the hydraulic line to the prescribed torque and purge the system. - When the operation is over, tighten the brake fluid bleed screw to the prescribed torque.
Page 252 B 125-250 Braking system Rear handlebar cover Rear - combined Refitting - Upon refitting, perform the operation but in reverse order. - Tighten the hydraulic line to the prescribed torque and purge the system. - When the operation is over, tighten the brake fluid bleed screw to the prescribed torque. WARNING BRAKE FLUID IS HYGROSCOPIC;...
Page 253 INDEX OF TOPICS COOL SYS OOLING SYSTEM...
Page 254: Circuit Diagram
B 125-250 Cooling system Circuit diagram ENGINE 250 COOLING CIRCUIT Specification Desc./Quantity Carburettor heating circuit Thermostat with by-pass Expansion tank COOL SYS - 254...
Page 255 B 125-250 Cooling system Specification Desc./Quantity Radiator ENGINE 125 COOL SYS - 255...
Page 256 B 125-250 Cooling system COOLING CIRCUIT Specification Desc./Quantity Carburettor heating circuit Thermostat with by-pass Expansion tank Radiator Water pump - overhaul ENGINE 125 - Check the water pump if noise in the bearings or liquid leaking from the drainage hole inside the cover is detected.
Page 257 B 125-250 Cooling system COOL SYS - 257...
Page 258 B 125-250 Cooling system Check components - Check that the rotor does not show abnormal wear or dents; - Check that the rotor shaft is not rusty; - Check that there is no rust on the bearing seats or the ceramic seal; - Check that the drive does not show dents and that it is perfectly integral with the steel hub.
Page 259 B 125-250 Cooling system - Insert the flywheel cover with bearings on the ap- propriate tool. - Insert the shaft together with the mechanical gas- kets on the bearings. - With the appropriate punch and socket, insert the shaft in the bearings and the drive until the end of stroke of the appropriate tool cannot be seen.
Page 260 B 125-250 Cooling system - Remove the complete flywheel cover - Remove the stator - Remove the pump cover by loosening the 3 fixing screws - Remove the sealing gasket The pump can be services using the special tool and a press. The special tool is designed to be used with the presses most commonly found in workshops.
Page 261 B 125-250 Cooling system Remove the ceramic seal from the pump shaft. Using a screwdriver, remove the ceramic ring and sealing gasket from the flywheel cover. N.B. IN THE EVENT YOU PLAN TO REUSE THE MECHANICAL SEAL, PAY ATTENTION DURING THE DISASSEMBLY STAGES IN ORDER TO NOT CHIP THE CERAMIC RING.
Page 262 B 125-250 Cooling system Before you reassemble, wash all the components and continue with the following checks. Flywheel cover: Check that there are no cracks or oxidation on the seat of the ceramic seal. Check the capacity loads of the bearings and of the seal ring.
Page 263 B 125-250 Cooling system Entrainment joint: Check that there is no abnormal wear on the seat for the oil seal seat and on the slots for the entrainment spring. Heat the flywheel cover using the heat gun N.B. IF THE JOB IS PERFORMED WITH THE STATOR MOUN- TED, HEAT FROM THE EXTERNAL SIDE OF THE COVER.
Page 264 B 125-250 Cooling system Mount the moving part of the ceramic seal on the shaft with the impeller. The rubber part must rest against the impeller. Position the flywheel cover on the press using the support base for the bearings that is part of the special tool.
Page 265 B 125-250 Cooling system While keeping the bearings in contact with the support base, line up the shaft with the press pis- ton and proceed with the driving. The driving depth is determined by the beat of the punch when it is in contact with the flywheel cover.
Page 266 B 125-250 Cooling system Fit the punch with the template of the entrainment joint to the press punch. Position the entrainment joint on the shaft and using the press, drive it to the depth determined by the punch. Specific tooling 020628Y Water pump service kit Lubricate the oil seal with motor oil.
Page 267 B 125-250 Cooling system distance of more than 1500 km. If leaks continue or in the event of real losses, the ceramic seal should be replaced. For these operations, observe the tools and instructions given in the relevant service station manuals. Note: The ceramic seal may be overhauled according to the following couplings: •...
Page 268 B 125-250 Cooling system 3) Replace the thermostat if it is not working prop- erly. - Visually check that the thermostat is not dam- aged. - Prepare a metal container with approx. 1 litre of water. - Immerse the thermostat, keeping it in the centre of the container.
Page 269 B 125-250 Cooling system - Tighten the two screw to the torque indicated be- low. Locking torques (N*m) Thermostat cover screws 3 ÷ 4 COOL SYS - 269...
Page 270 INDEX OF TOPICS CHAS HASSIS...
Page 271: Rear Rack
B 125-250 Chassis Seat - Remove the saddle by loosening the three re- taining screws indicated in the figure; Side fairings - Remove side bumpers by removing the mounting screws shown in the figure (one on each side). Rear rack - Loosen the two mounting screws and remove the battery cover.
Page 272: Instrument Panel
B 125-250 Chassis Rear handlebar cover - Remove the front handlebar cover. - Remove the 3 screws shown in the photograph. - Remove the 2 screws on the rear part of the han- dlebar cover shown in the photograph. See also Front handlebar cover Instrument panel - Remove the rear handlebar cover.
Page 273 B 125-250 Chassis Headlight assy. - Remove the headlight assembly by loosening the 4 fixing screws, two of which are shown in the fig- ure and two located further down. - Separate the electrical connectors; - Pull out the headlight as- sembly.
Page 274 B 125-250 Chassis - Loosen the 2 screws shown in the figure. - Remove the legshield. See also Headlight assy. Frame central cover Knee-guard - Remove the legshield; - Remove the 2 fixing screws of the fuse box in the front glove box; - Separate the electrical connections;...
Page 275 B 125-250 Chassis Removing the ignition key-switch when on *off* - Remove the shield back plate. - Remove the immobilizer aerial as shown in the figure. - Detach the electrical wiring. - Remove the ignition key-switch, by removing the spring retainer shown in the figure. - Lightly push the master-cylinder and extract the lock from the notch shown in the figure.
Page 276 B 125-250 Chassis Removing the ignition key-switch when on *lock* In position "Lock", it is not possible to access the cylinder retaining spring. The spring must then be removed as shown in the figure, allowing the lock spring to be pressed out. N.B.
Page 277 B 125-250 Chassis Footrest - Remove the central cover. - Remove the RHS footrest mat. - Loosen the eight footrest mounting screws. - Remove the RHS footrest. - Repeat the same operations for the LHS footrest. See also Frame central cover Side fairings - Remove the saddle.
Page 278: Rear Mudguard
B 125-250 Chassis See also Seat Rear rack Frame central cover Taillight assy. Rear mudguard - Loosen the 4 fixing screws, 2 of which are indi- cated in the figure and the other 2 located on the opposite side under the air filter; - Remove the rear mudguard.
Page 279: Fuel Tank
B 125-250 Chassis Helmet bay - Remove the side fairings; - Disconnect the elec- trical connections; - Undo the 8 fixing screws, 4 of which are inside the compartment; - Remove the license plate holder support by undoing the 4 fixing screws shown in the figure and disconnecting the electrical cable harness;...
Page 280: Front Mudguard
B 125-250 Chassis Front mudguard - Remove the retaining screw of the cable lead through support on the right-hand side of the mud- guard. - Loosen the 3 fixing retaining screws indi- cated in the figure and remove the mudguard. Radiator fan - Remove the front wheel housing.
Page 281 INDEX OF TOPICS PRE DE DELIVERY...
Page 282 B 125-250 Pre-delivery Carry out the listed tests before delivering the vehicle. Warning- be very careful when handling fuel. Aesthetic inspection Appearance check: - Paintwork - Fitting of plastics - Scratches - Dirt Tightening torques inspection Lock check - Safety locks - clamping screws Safety locks Rear shock absorber upper fixing...
Page 283 B 125-250 Pre-delivery - Horn - Starter CAUTION TO ENSURE MAXIMUM PERFORMANCE, THE BATTERY MUST BE CHARGED BEFORE USE. INADEQUATE CHARGING OF THE BATTERY WITH A LOW LEVEL OF ELECTROLYTE BEFORE IT IS FIRST USED SHORTENS BATTERY LIFE. WARNING BEFORE RECHARGING THE BATTERY, REMOVE THE CAPS OF EACH CELL. KEEP THE BATTERY AWAY FROM NAKED FLAMES OR SPARKS WHILE IT IS CHARGED.
Page 284 B 125-250 Pre-delivery - Abnormal noise Static test Static control after the test ride: - Starting when warm - Starter operation - Minimum hold (turning the handlebar) - Uniform turning of the steering - Possible leaks CAUTION CHECK AND ADJUST TYRE PRESSURE WITH TYRES AT AMBIENT TEMPERATURE. CAUTION NEVER EXCEED THE RECOMMENDED INFLATION PRESSURES OR TYRES MAY BURST.
Page 285 INDEX OF TOPICS TIME...
Page 286 B 125-250 Time Engine ENGINE Code Action Duration 001001 Engine from frame - Removal and re- fit. 003064 Engine oil - Change 003057 Engine retainer - Tighten nuts TIME - 286...
Page 287 B 125-250 Time Crankcase CRANKCASE Code Action Duration 001153 Crankcase halves gasket - Replace- ment 001133 Engine crankcase - Replacement TIME - 287...
Page 288 B 125-250 Time Crankshaft CRANKSHAFT Code Action Duration 001099 Oil seal, flywheel side - Replacement 001117 Crankshaft - Replacement TIME - 288...
Page 289 B 125-250 Time Cylinder assy. CYLINDER- PISTON Code Action Duration 001002 Cylinder-Piston - Replacement 001154 Pin ring piston unit - Service TIME - 289...
Page 290 B 125-250 Time Cylinder head assy. VALVE HEAD Code Action Duration 001126 Head - Replacement 001045 Valves - Replacement 001049 Valves - Adjustment 001056 Head gasket - Replacement 001083 Thermistor - Replacement 001057 Thermostat - Replacement TIME - 290...
Page 291 B 125-250 Time Rocker arms support assy. CAMSHAFT - ROCKING LEVERS Code Action Duration 001148 Valve rocking levers - Replacement 001044 Camshaft - Replacement TIME - 291...
Page 292: Cylinder Head Cover
B 125-250 Time Cylinder head cover HEAD COVER Code Action Duration 001093 Spark plug - Replacement 001089 Head cover - Replacement 001088 Head cover gasket - Replacement 001074 Oil vapour recovery pipe - Replace- ment TIME - 292...
Page 293 B 125-250 Time Chain tensioner CHAIN TIGHTENER Code Action Duration 001129 Chain tensioner - Service and Re- placement 001124 By pass lubrication - Replacement TIME - 293...
Page 294: Oil Filter
B 125-250 Time Oil filter OIL FILTER Code Action Duration 001123 Oil filter - Replacement 001160 Oil pressure sensor - Replacement TIME - 294...
Page 295: Driven Pulley
B 125-250 Time Driven pulley DRIVEN PULLEY Code Action Duration 001022 Clutch - Replacement 003072 Clutch unit - Wear check 001012 Driven pulley - Service 001110 Driven pulley - Replacement 001155 Clutch bell housing - Replacement TIME - 295...
Page 296 B 125-250 Time Oil pump PUMP - OIL SUMP UNIT Code Action Duration 001125 Chain guide pads - Replacement 001051 Belt/ Timing chain - Replacement 001042 Oil pump - Service 001112 Oil pump - Replacement 001122 Oil pump chain - Replacement 001121 Chain cover oil seal - Replacement 001130...
Page 297 B 125-250 Time Final gear assy. FINAL DRIVE Code Action Duration 001010 Gear reduction unit - Inspection 001156 Gear reduction unit cover - Replace- ment 003065 Gear box oil - Replacement 004125 Rear wheel axle - Replacement TIME - 297...
Page 298 B 125-250 Time Driving pulley PULLEY REAR VIEW Code Action Duration 001086 rear-view half-pulley - Replacement 001011 Driving belt - Replacement 001066 Driving pulley - Removal and Refit- ting 001006 driving pulley - Service TIME - 298...
Page 299: Flywheel Magneto
B 125-250 Time Transmission cover TRANSMISSION COVER Code Action Duration 001135 Transmission cover bearing - Re- placement 001096 Transmission crankcase cover - re- place 001131 Transmission air intake - Replace- ment Flywheel magneto Version 250 TIME - 299...
Page 300 B 125-250 Time MAGNETO FLYWHEEL Code Action Duration 001087 Flywheel cover - Replacement 001113 Water pump - Replacement 001173 Rotor - replace 001067 Stator - Replacement 001104 Start-up freewheel - Replacement 001151 Start-up driven gearing - Replace- ment Version 125 MAGNETO FLYWHEEL AND SECONDARY AIR Code Action...
Page 301 B 125-250 Time Code Action Duration 001162 Secondary air housing - Replace- ment 001174 SAS valve - Replacement 001163 SAS valve / Head connection - Re- placement Carburettor CARBURETTOR Code Action Duration 001013 Intake manifold - Replacement 007020 Carburettor heat. pipes - Replace- ment 001008 Carburettor - Inspection...
Page 302 B 125-250 Time Exhaust pipe MUFFLER Code Action Duration 001009 Muffler - Replacement 001095 Muffler guard - Replacement 001092 Exhaust manifold - Replacement TIME - 302...
Page 303: Air Cleaner
B 125-250 Time Air cleaner AIR CLEANER Code Action Duration 001014 Air filter - Replacement/Cleaning 001015 Air filter box - Replacement 004122 Carburettor air cleaner attachment - Replacement TIME - 303...
Page 304 B 125-250 Time Frame CHASSIS Code Action Duration 004001 Chassis - Replacement TIME - 304...
Page 305 B 125-250 Time Centre-stand CENTRE AND SIDE STANDS Code Action Duration 004004 Stand - Replacement 004102 Side stand - Replacement 005079 Stand switch - Replacement TIME - 305...
Page 306 B 125-250 Time Legshield spoiler LEGSHIELD - SPOILER Code Action Duration 004064 Legshield - Replacement 004053 Spoiler - Replacement TIME - 306...
Page 307 B 125-250 Time Side fairings SIDE COVERS Code Action Duration 004085 Fairing (1) - Replacement 004012 Rear side panels - Replacement 004052 Bumper - Replacement TIME - 307...
Page 308 B 125-250 Time Footrests MATS AND COVERS Code Action Duration 004075 Front mat - Replacement 004079 Passenger footrest (1) - Replace- ment 004015 Footrests - Remov. and Refit. TIME - 308...
Page 309 B 125-250 Time Rear cover REAR SHIELD Code Action Duration 004065 Legshield rear section - Remov. and Refit. 004081 Glove box door - Replacement TIME - 309...
Page 310 B 125-250 Time Central cover CENTRAL COVER Code Action Duration 004011 Frame central cover - Replacement 002082 Fuel tank cap opening drive - Re- placement TIME - 310...
Page 311 B 125-250 Time Underseat compartment HELMET COMPARTMENT- SEAT ELECTRIC OPENING-LICENCE PLATE HOLDER Code Action Duration 002083 Saddle opening transmission - Re- placement Saddle opening transmis- sion - Replacement 004016 Helmet compartment - Remov. and Refit. 004106 Underseat band - Replacement 004136 License plate holder support - Re- placement...
Page 312 B 125-250 Time Mudguard FRONT AND REAR MUDGUARDS Code Action Duration 004009 Rear mudguard - Replacement 004002 Front mudguard - Replacement TIME - 312...
Page 313 B 125-250 Time Fuel tank FUEL TANK Code Action Duration 005010 Tank float - Replacement 004109 Fuel tank breather - Replacement 004005 Fuel tank - Replacement 004007 Fuel valve - Replacement TIME - 313...
Page 314 B 125-250 Time Expansion tank EXPANSION TANK Code Action Duration 007001 Expansion tank - Replacement 007013 Expansion tank - radiator connection pipe - Replacement 001052 Coolant and air bleeding - Replace- ment TIME - 314...
Page 315 B 125-250 Time Radiator RADIATOR Code Action Duration 007014 Radiator thermal switch - Replace- ment 007002 Radiator water - Replacement 007016 Complete fan with support - Replace- ment 007003 Coolant delivery and return pipe - Re- placement TIME - 315...
Page 316 B 125-250 Time Rear shock-absorber REAR SHOCK ABSORBER Code Action Duration 003007 Rear shock absorber - Remov. and Refit. TIME - 316...
Page 317 B 125-250 Time Steering column bearings STEERING FIFTH WHEELS Code Action Duration 003051 Fork unit - Replacement 003079 Fork stem - Replacement 003048 Fork oil seal - Replacement 004119 Bearing/upper steering fifth wheel - Replacement 003002 Steering fifth wheel - Replacement 003073 Steering clearance - Adjustment 003010...
Page 318: Handlebar Covers
B 125-250 Time Handlebar covers HANDLEBAR COVER Code Action Duration 004018 Handlebar front section - Replace- ment 004019 Handlebar rear section - Replace- ment 006013 Handlebar front part - Painting 006014 Handlebar rear part - Painting TIME - 318...
Page 319 B 125-250 Time Handlebar components HANDLEBAR COMPONENTS Code Action Duration 002060 Throttle grip - Replacement 002037 Brake or clutch lever - Replacement 002071 Left knob - Replacement 002024 Front brake pump - Removal and Re- fitting 002067 Rear brake pump - Replacement 003001 Handlebar - Replacement 002063...
Page 320 B 125-250 Time Swing-arm SWINGING ARM Code Action Duration 001072 Swinging arm - Engine-chassis con- nection - Replacement 004058 Silent block - Replacement TIME - 320...
Page 321 B 125-250 Time Brake hoses BRAKE PIPING Code Action Duration 002039 Front brake calliper - Replacement 002040 Front brake calliper - Service 002021 Front brake piping - Replacement 002047 Front brake fluid and system bleed- ing plug - Repl. 003070 Front brake pads/shoes - Check for wear 003071...
Page 322 B 125-250 Time Seat SADDLE Code Action Duration 004003 Saddle - Replacement TIME - 322...
Page 323: Seat Lock
B 125-250 Time Seat lock SADDLE LOCK MECHANISM Code Action Duration 004054 Saddle lock catch - Replacement TIME - 323...
Page 324 B 125-250 Time Instrument panel INSTRUMENT PANEL Code Action Duration 005014 Odometer - Replacement 005038 Instrument panel warning light bulbs - Replacement TIME - 324...
Page 325 B 125-250 Time Rear rack LUGGAGE RACK Code Action Duration 004008 Luggage rack - Replacement TIME - 325...
Page 326 B 125-250 Time Locks LOCKS Code Action Duration 005016 Key switch - Replacement 004010 Anti-theft lock - Replacement TIME - 326...
Page 327: Turn Signal Lights
B 125-250 Time Turn signal lights TURN INDICATOR LIGHTS Code Action Duration 005002 Front headlamp - change 005005 Taillight - Replacement 005008 Headlight bulbs - Replacement 005031 Licence plate light bulb - Replace- ment 005032 Licence plate light glass - Replace- ment 005044 Front lights cable unit - replace...
Page 328: Front Wheel
B 125-250 Time Front wheel FRONT WHEEL Code Action Duration 002041 Brake disc - Replacement 003037 Front wheel rim - Remov. and Refit. 003038 Front wheel axle - Remov. and Refit. 003040 Front wheel bearings - Replacement 003047 Front tyre - Replacement 003063 Tyre pressure - Check 004123...
Page 329: Rear Wheel
B 125-250 Time Rear wheel REAR WHEEL Code Action Duration 001016 Rear wheel - Replacement 001071 Rear wheel rim - Removal and Refit- ting 002070 Rear brake disc - Replacement 003063 Tyre pressure - Check 003077 muffler/rear shock absorber support arm - Service 004126 Rear wheel tyre - Replacement...
Page 330: Electric Start
B 125-250 Time Electric start ELECTRICAL START UP Code Action Duration 001141 Belt anti-vibration roller - Replace- ment 001020 Starter motor - Replacement 001017 Start-up pinion - Replacement TIME - 330...
Page 331: Fuel Pump
B 125-250 Time ELECTRICAL START-UP Code Action Duration 001020 Starter motor - Replacement 001017 Start-up pinion - Replacement Fuel pump TIME - 331...
Page 332 B 125-250 Time FUEL PUMP Code Action Duration 004073 Fuel pump - Replacement 004137 Carburettor pump hose - Replace- ment 004086 Vacuum fuel pump pipe - Replace- ment 004089 Tank-pump hose - Replacement 004072 Fuel filter - Replacement Electric devices TIME - 332...
Page 333 B 125-250 Time ELECTRIC DEVICES Code Action Duration 001023 Control unit - Replacement 001069 HV coil - Replacement 001094 Spark plug hood - Replacement 005001 Electrical system - Replacement 005003 Horn - Replacement TIME - 333...
Page 334 B 125-250 Time Code Action Duration 005035 Headlight remote control - Replace- ment 005052 Fuse (1) - Replacement 005054 Fuse block (1) - Replacement 005114 Electrical system - Service Secondary air box ECONDARY AIR HOUSING Code Action Duration 001162 Secondary air housing - Replace- ment 001161 Secondary air filter - Replacement /...
Page 335 Air filter: 48 Battery: 63, 80, 96, 97 Brake: 240, 241, 243, 245–247, 250, 251, 321 Carburettor: 13, 42, 189, 200, 301 Engine oil: 49 Engine stop: Fuel: 62, 189, 279, 313, 331 Fuses: 95 Headlight: 54, 273, 274 Horn: Hub oil: 47 Identification: 8 Instrument panel: 272, 324...
Page 336 Transmission: 9, 62, 103, 124, 299 Tyres: 10...

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