Do you have a question about the MRT 50 and is the answer not in the manual?
Questions and answers
Jonas Lindqvist
April 24, 2025
Clutch does not work. No problem with kabel. The lever on the motor is turning ok and the axel is also turning but the kluts is not working. Something inside the motor must have got loos. How much of the motor must be taken apart? And to what kost aproximately.
Contents Chassis INTRODUCTION AUPDATES FOR THE MANUALS SYMBOLS USED ABBREVIATIONS USED IN THE MANUAL GENERAL WORK RULES RECOMMENDATIONS LEARNING ABOUT THE MOPED MAINTENANCE OPERATIONS TECHNICAL SPECIFICATIONS AND CHARACTERISTICS UNPACKING “AESTHETIC APPEARANCE” CHECK DETAILS FOR IDENTIFICATION SAFETY LABEL IDENTIFYING THE MAIN ELEMENTS CONTROLS KEYS STEERING LOCK...
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Contents Chassis REMOVAL 1. SEAT 2. FRONT SIDE COVERS 3. REAR SIDE COVERS 4. REAR COWLING 5. CHAIN PROTECTOR 6. REAR MUDGUARD 7. REAR MUDGUARD 8. FILTER CANISTER 9. AIR FILTER 10. EXHAUST PIPE 11. SILENCER 12. “AIS” SYSTEM (Secondary air valve) 13.
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Contents Chassis REMOVAL 31. TURN INDICATORS CONTROL UNIT 32. REGULATOR 33. E.C.U. 34. ODOMETER TAKE-OFF 35. HANDLEBARS 36. STEERING 37. FRONT WHEEL 38. FRONT BRAKE CYLINDER 39. FRONT BRAKE CALLIPER 40. FRONT BRAKE DISK 41. CLUTCH LEVER 42. REAR WHEEL 43.
Introduction Chassis SYMBOLS USED IN THE MANUAL ATTENTION! Practical advice and information that refers to the safety of the motorcyclist (user of the machine) and the features that maintain the condition and integrity of the machine itself.. ATTENTION! Descriptions that relate to work that is dangerous for the te- chnical maintenance staff, repair staff, other workshop staff or for those from outside, for the environment, for the machine and for the equipment.
Introduction Chassis ABBREVIATIONS USED IN THE MANUAL Figure T Tq Tightening torque Page Part Section Diag Diagram Table Bolt N.B.: The illustrations frequently show securing or adjustment bolts or screws, indicated by the letter B. The number following this letter indicates the quantity of identical bolts (B) or screws to be found on the unit or component being described and its corresponding illustration.
Introduction Chassis GENERAL WORK RULES • The tips, recommendations and warnings that follow are aimed at ensuring that work is carried out in a rational way and with maximum operational safety, thereby eliminating significantly the chances of accidents, injury and damages of any nature and downtimes. They should therefore be scrupulously observed.
Introduction Chassis RECOMMENDATIONS • Before beginning any work on the moped, wait for each and every one of the machine’s components to cool down completely. • If the operations envisage the use of two mechanics, they need to agree in advance on the tasks to be performed and synergies.
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Introduction Chassis Never use naked flames under any circumstances. Never leave open and unsuitable containers containing petrol where others are passing, close to heat sources, etc. Never use petrol as a cleaner to clean down the machine or to wash the workshop floor. Clean the various components with detergent with a low flammability rating.
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Familiarising yourself with the Familiarising yourself with the moped moped...
Familiarising yourself with the moped Chassis SERVICE SERVICE SERVICE MAINTENANCE OPERATIONS EVERY 3.500 3.000 · · · Check the braking system · Check the transmission oil level Change Change · · · Check chain tension and wear · · Check suspensions ·...
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Familiarising yourself with the moped Chassis Transmission oil Type CASTROL MTX SAE 10W 30 Quantity 820 c.c. Air filter Wet-type foam cartridge Fuel 95 octane lead-free petrol Type 6,32 L. Fuel tank capacity Carburettor Dellorto PHBN 16 HS Spark plug NGK BR 9 ES Type 0,6 - 0,7 mm.
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CASTROL 15 W 20 FORK OIL , 245 cc per Rear Hydraulic shock absorber Suspension: MRT 50 PRO / MRT 50 PRO SM Front 40 mm Ø inverted hydraulic forks CASTROL 10 W FORK OIL , 325 cc per bar...
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Familiarising yourself with the moped Chassis TABLE OF TIGHTENING TORQUES Element Kg*m Notes Front wheel bolt 38 - 52 3,8 - 5,2 Front wheel bolt lock 17 - 23 1,7 - 2,3 Rear wheel bolt 72 - 98 7,2 - 9,8 Front/rear brake calliper 24 - 36 2,4 - 3,6...
Familiarising yourself with the moped Chassis UNPACKING Unpack the moped following the directions present in the packaging itself, which must then • be disposed of in accordance with existing regulations. “AESTHETIC APPEARANCE” CHECK • Check visually that all components made of plastic material are fitted correctly and that the machine does not have any visible scratches, marks, etc.
Familiarising yourself with the moped Chassis IDENTIFICATION OF MAIN ELEMENTS (left-hand side) 1. Headlight. MRT SM 2. Right-hand controls. 3. Left-hand controls. 4. Seat. 5. Prop stand. 6. Gear change pedal. 7. Fuel tank. IDENTIFICATION OF MAIN ELEMENTS (right-hand side) 8.
Familiarising yourself with the moped Chassis INSTRUMENT PANEL Turn indicators indicator light This indicator light flashes when the turn indicator switch is moved to the left or to the right. Oil level indicator light This indicator light comes on when the oil level is low. Oil temperature indicator light This indicator light comes on when the oil temperature is too high.
Familiarising yourself with the moped Chassis TYRES dimensions MRT SM dimensions FRONT 80/90 - 21 48P FRONT 100/80 - 17 52S 110/80 - 18 58P 130/70 - 17 62S REAR REAR CHECKING THE PRESSURE Tyre pressures should be checked and adjusted with the tyres at ambient temperature. MRT SM FRONT 1,7 kg / cm2...
Familiarising yourself with the moped Chassis COOLANT Check 1. Remove the cap (A/F-12) with the engine cold, first allowing the residual pressure to escape. 2. Check the level of coolant with engine cold, because this level varies according to the temperature of the engine.
Familiarising yourself with the moped Chassis ENGINE OIL Inside, the tank contains an electrical contact that turns on the reserve indicator light on the dashboard when the tank is low on oil. To top up the oil, remove the cap (A(F-14) and fill up, taking great care. Recommended oil: SYNTHETIC OIL FOR 2-STROKE ENGINES.
Familiarising yourself with the moped Chassis BRAKE FLUID Check When checking the fluid level, turn the han- dlebars to ensure that the top of the master cylinder is level. Check that the brake fluid level is above the minimum level mark on the rear brake fluid reservoir, and check that there is fluid for the front brake by looking through the inspection hole in the cylinder.
Familiarising yourself with the moped Chassis ADJUSTING THE TRANSMISSION CHAIN TENSION The chain is adjusted by loosening the rear wheel shaft and screwing in or unscrewing the nuts and bolts adjacent to the shaft (A/ F-19), ensuring that there is the same distance on both sides of the shaft at all times.
Removal Chassis 1. SEAT Unscrew the two bolts (A/F-1) situated at the back of the seat. Then lift the seat at the back and pull it backwards to free it from the front anchorage. 2. FRONT SIDE COVERS * Remove the seat. Unscrew the 3 screws (A/F-3).
Removal Chassis 4. REAR COWLING * Remove the seat and the front side covers. Unscrew the 4 bolts (A/F-5) located inside the rear wheel arch. Then pull the cowling backwards to free it from the chassis (B/F-6). Once the rear mudguard has been freed, unscrew the 2 screws (C/F-7).
Removal Chassis 6. FRONT MUDGUARD Unscrew the 4 bolts (A/F-9) located underneath the mudguard. 7. REAR MUDGUARD Unscrew the 4 bolts (A/F-10) located inside the rear wheel arch. Then pull the cowling backwards to free it from the chassis (B/F-11). Disconnect the rear turn indicators (C/F-12) and remove them (see section F-10 F-11...
Removal Chassis 8. FILTER CANISTER * Disconnect the rear light and remove it (see section). *Remove the seat and the rear side covers. Remove the 2 bolts (A/F-13) from the top. Unscrew the 2 bolts (B/F-14) located inside the rear wheel arch. Remove the clamp (C/F-15) between the AIS system pipe connection and the filter nozzle.
Removal Chassis 9. AIR FILTER * Remove the seat. Remove the screw (A/F-17) from the filter cover. Loosen the nut (B/F-18) and withdraw the filter. F-17 F-18 ATTENTION: Ensure that the part regulating the air intake is in the right position (C/F-19). F-19...
Removal Chassis 10. EXHAUST PIPE * Remove the rear left-hand fairing and the silencer. Loosen the clamp (A/F-20) attaching the exhaust pipe to the silencer. Remove the 2 springs (B/F-21) attaching the exhaust to the engine at the front and the screw (C/F-21) on the Silentbloc.
Removal Chassis 11. SILENCER * Remove the seat and the front right-hand cover. Loosen the clamp (A/F-23) securing the exhaust pipe to the silencer. Then unscrew the 2 bolts (B/F-24) securing the silencer to the chassis. To extract it, pull the silencer backwards. ATTENTION: Before removing the silencer, make sure it has cooled down.
Removal Chassis 13. FUEL TANK * Remove the seat and the front side covers. ATTENTION: Before removal, shut the fuel tap on the tank (A/F-26). Remove the fuel tap pipe from the carburettor (B/F-26). Extract the breather pipe (C/F-27). Unscrew the screw (D/F-28) securing the tank to the chassis. Then remove the tank (E/F-29) by pulling it upwards.
Removal Chassis 14. OIL TANK * Remove the seat, the front left-hand side co- ver, the oil sensor and the oil filter. Unscrew the 2 screws (A/F-30) securing the tank to the chassis, and remove it. F-30 15. OIL SENSOR * Remove the front left-hand cover.
Removal Chassis 17. RADIATOR * Remove the seat and the front side covers. Drain the cooling circuit via the drain screw (A/F-33). Loosen the clips that attach the engine hoses to the radiator (B/F-34). Then unscrew the 2 bolts (C/F-35) securing the radiator to the chassis. F-33 F-34 F-35...
Removal Chassis 19. GEAR LEVER Unscrew the securing bolt (A/F-37). Then pull off the lever, taking care not to damage the shaft splines. F-37 20. KICK-START LEVER Unscrew the bolt (A/F-38) and extract the lever by pulling it off. ATTENTION: Refitting the lever in a diffe- rent position to the original may reduce the travel during kick-starting.
Removal Chassis 22. SHOCK ABSORBER * Remove the seat, the front side covers, the rear fairings and the filter canister. Unscrew the bolt and the top nut (A/F-40-42) securing the shock absorber to the chassis. Unscrew the bottom bolt and the nut (B/F-41-43) from the rod (MRT SM version). ATTENTION: Before removal, secure the chassis at the bottom to prevent the swinging arm and the wheel from falling.
Removal Chassis 23. FUEL TRANSMISSION/OIL MIXER Remove the 2 bolts from the cover (A/F-44). Pull back the tensioner and withdraw the throttle cable. F-44 F-45 24. CARBURETTOR * Remove the seat, the front faiings and the fuel tank (only withdraw it). Unscrew the clamp securing the carburettor to the filter canister.
Removal Chassis 25. ENGINE * Remove the seat, the front and rear side covers, the fuel tank and the transmission chain. Disconnect the 2 heater pipes from the cylinder head, disconnect the suction pipes (A/F-47) and seperate the connector from the spark plug. Disconnect the thermo-switch cable.
Removal Chassis 26. FRONT HEADLIGHT Unscrew the 2 bolts (A/F-50) and tilt the light forwards to aid the operation. Disconnect the light (B/F-51) from the general wiring. Unscrew the screw (C/F-52) securing the nut on the inside. Unscrew the 5 screws (D/F-53) securing the light to the light holder. Unscrew the headlight height adjustment screw (E/F-54).
Removal Chassis 27. INSTRUMENT PANEL Disconnect the cable from the instrument panel (A/F-55). Then unscrew the 2 screws (B/F-56) securing it to the chassis. F-55 F-56 28. FRONT TURN INDICATORS Unscrew the 2 bolts (A/F-57) and tilt the light forwards to aid the operation. Disconnect the light (B/F-58) from the general wiring.
Removal Chassis 29. REAR TURN INDICATORS * Carry out the first 2 steps in section 4. Rear cowling (F5-F6). ATTENTION: Before removing the lights, pay attention to the sequence of the terminals for later refitting (see wiring diagram). Disconnect the cables (A/F-60) from the general wiring. Then loosen the screw (B/F-61) securing the nut on the inside, and pull out the cable to remove the light.
Removal Chassis 31. TURN INDICATORS CONTROL UNIT * Tilt the light panel forwards to aid the ope- ration. Disconnect the regulator from the wiring (A/F-64) and remove it from the securing rub- ber (B/F-64). F-64 32. REGULATOR Disconnect the regulator from the wiring (A/F-65). Then, unscrew the bolt (B/F-66) to remove it.
Removal Chassis 34. ODOMETER TAKE-OFF Remove the bolt (A/F-68-69) and disconnect from the general wiring (B/F-70). To disconnect the take-off, tilt the front headlight holder. MRT SM F-68 F-69 F-70 F-71 distance < 1mm ATTENTION: the distance between the bolts on the disks and the sensor must be bet- ween 1 and 2 mm.
Removal Chassis 35. HANDLEBARS * Remove the controls on each end. Unscrew the 4 bolts (A/F-72-73) and remove the handlebars. MRT SM F-72 F-73 36. STEERING Unscrew the 4 handlebar screws (A/F-74-76). Loosen the 2 side bolts (B/F-75-77) to aid its extraction. Extract the top nut (C/F-74-77) and remove the top plate.
Removal Chassis 37. FRONT WHEEL MRT SM MRT SM Unscrew the nut on the left-hand side. Loosen the 2 shaft securing bolts (A/F-78) lo- cated on the forks. Unscrew the wheel shaft and remove it. F-78 Loosen the wheel shaft securing bolt (A/F-79) located on the forks.
Removal Chassis 39. FRONT BRAKE CALLIPER MRT SM MRT SM Unscrew the connector using the bolt (A/F-81). Then unscrew the 2 bolts (B/F-81) securing the calliper to the front forks. F-81 Unscrew the connector using the bolt (A/F-82). Then unscrew the 2 bolts (B/F-82) securing the calliper to the front forks.
Removal Chassis 41. CLUTCH LEVER Disconnect the clutch cable (A/F-85) and the choke cable (B/F-86). Then unscrew the 2 screws (C/F-85) and remove the lever. F-85 F-86 42. REAR WHEEL Slacken the wheel tensioners. Remove the nut (A/F-87) located on the right-hand side. Push the wheel forwards to free the chain from the wheel sprocket.
Removal Chassis 43. REAR BRAKE CALLIPER MRT SM MRT SM Unscrew the connector using the bolt (A/F-89). Then unscrew the 2 bolts (B/F-89) securing the calliper to the calliper bracket. F-89 Unscrew the connector using the bolt (A/F-90). Next, remove the rear wheel to free the ca- lliper.
Removal Chassis 45. REAR BRAKE CYLINDER MRT SM MRT SM Remove the protector from the brake cylinder by removing the 2 bolts (A/F-93). To remove the cylinder it is necessary to dis- connect the STOP switch (B/F-94) and unscrew F-93 Remove the clamp (C/F-94) from the brake fluid supply tube and drain into a container.
Removal Chassis 46. SWINGING ARM * Remove the chain, the rear brake calliper, the rear wheel and the shock absorber. Unscrew the nut (A/F-96) and withdraw the shaft from the right-hand side. F-96 47. TRANSMISSION CHAIN Remove the 2 bolts (A/F-97) securing the protector and remove it. Extract the clip (B/F-98) securing the connector link and remove the chain.
Removal Chassis 48. FRONT FOOTRESTS Unscrew the bolt (A/F-99-100) securing the bottom nut. ATTENTION: Make a note of the position of the spring so that it can be refitted correctly. MRT SM F-99 F-100 49. REAR FOOTRESTS Unscrew the bolt (A/F-101) securing the bottom nut. F-101...
Electrical system Chassis 1. PRECAUTIONS There are a number of important precautions to be taken before beginning to inspect or repair the electrical system. • Special attention must be paid to the polarity of the battery. • Always check the condition of the battery on beginning any repair. •...
Electrical system Chassis 3. TROUBLESHOOTING To check if the lighting system is working properly, use the meter to check the voltage. Regulator output data: Perform these checks with the regulator and the magneto connected. • The A.C. voltage (Yellow cable) should be I3.8 to 14.5V. at 6,000 R.P.M. (meter in A.C. position).
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Electrical system Chassis CHECKING THE MAGNETO The resistance of components should be checked when the machine is cold. Impulse capture coil resistance. Connect the meter between the Red and White cables. Resistance: 130Ω +/- 20% a 20º C Spark condenser charging coil resistance. Connect the meter between the Green and White cables.
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Electrical system Chassis If the checks reveal the values to be correct and the problem persists, the magneto wiring must be checked. If this is correct, the CDI coil should be renewed. Important precautions: • Never connect or disconnect cables or connections with the ignition on or the engine running.
Electrical system Chassis 5. LIGHTING SYSTEM Adjusting the height of the front headlight beam With the rider seated on the machines, the headlight beam should be adjusted in such a way that the main beam is situated below the headlight horizontal. In case of having to change a bulb, avoid touching the inside of the headlight with the hands.
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Electrical system Chassis Checking the right controls: Light switch, turn indicator switch and horn button. TURN INDICATOR SWITCH HORN LIGHT BUTTON R/HAND SWITCH L/HAND Check that there is a circuit between the connector cables. Horn button Pressing the horn button should create a circuit between the cables. Colour: PINK/BLACK Turn indicators switch R/HAND position.
Electrical system Chassis 6. CHECKING THE INSTRUMENTACTION DIAGRAM OF THE MAE INSTRUMENT PANEL CONNECTOR PIN FUNCTIONS CONNECTOR PIN FUNCTIONS DIAGRAM OF THE KOSO INSTRUMENT PANEL CONNECTOR PIN FUNCTIONS CONNECTOR PIN FUNCTIONS...
Electrical system Chassis 7. SENSORS Checking the functioning of the indicator lights. Temperature and oil indicator: Checking these requires making a bridge to earth with each cable corresponding to the graphic for the instrument panel. Turn indicators indicator: To check the turn indicators indicator light, connect the green cable to earth and the brown to positive.
Electrical system Chassis 8. PROGRAMMING THE MAE INSTRUMENT PANEL The service symbol only appears on machines with cubic capacity greater than 50 cc. Mode button The dashboard has a button that is normally The following chapters set out the functions and use of this button.
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Electrical system Chassis The speed is updated every 0.5 seconds. The default parameters are: ENDURO Circunf. Tech. const. Max. Over- Pulse./wheel Model Resolution (imp./min.) (mm) revolution speed estimation 50cc 2180 45,87 p. up 6% constante en 1 km/h 240 km/h 149 mph toda la escala 1 mph...
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Electrical system Chassis This information is stored permanently in a non-volatile memory (E2prom updated every kilometre). If this memory contains no data, the screen will display 00000. This information is always calculated in kilometres. However, it can be displayed in either kilometres (default) or in miles.
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Electrical system Chassis The average speed is calculated every 0.1 km (or 0.1 miles depending on the unit of measu- rement selected) and an excessive speed is not permitted. If the data is outside the values allo- wed, ------ will be displayed, as shown in the figure.
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Electrical system Chassis This data is not saved permanently in the E²PROM. The meter for this setting can be reset to zero by pressing the adjustment button for 2 seconds, together with the LAP function, until the value 00’00” is displayed. Resetting this meter to zero, either with the machine halted or in motion, also causes the zeroing of the TD and AVE functions.
Electrical system Chassis Oil alarm The OIL alarm displays the ( ) symbol on the LCD, and the corresponding LED lights up. This alarm is triggered when a low oil level activates the electrical contact, and turns off when the oil level is higher than the minimum and the contact opens. To prevent false messages, the alarm delays 5 seconds in turning on and off.
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Electrical system Chassis MAE WIRING DIAGRAM...
Electrical system Chassis 9. PROGRAMMING KOSO INSTUMENT PANEL N.B.: The notes contain detailed information about the installation. ( ) Processes to be followed is obligatorily to avoid the problems caused by an incorrect installation. PRESS PRESS THE BUTTON DOWN FOR THREE SECONDS Instructions for use Indicators Thermometer level indicator...
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Electrical system Chassis Adjustment of the speed measurement unit. On the main screen, hold down the selection and adjustment buttons for 3 seconds to access the adjustment of the speed measure- ment unit. Press the adjustment button to select the unit of measurement.
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Electrical system Chassis Press the selection button to access the tyre circumference adjustment. E.g.: The tyre circumference is 1,300 mm. Press the selection button to change to the digit to be adjusted. E.g.: The original adjust- ment is 1,000mm. The 1 flashes. N.B.: Tyre circumference adjustment interval: 300~2,500 mm;...
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Electrical system Chassis E.g.: the sensor point to be adjusted is 6. Press the selection button to change to the digit to be adjusted. E.g.: the original setting is 1 point. The 0 flashes. N.B.: Sensor point adjustment interval: 1~60 points.
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Electrical system Chassis KOSO WIRING DIAGRAM...
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Do you have a question about the MRT 50 and is the answer not in the manual?
Questions and answers
Clutch does not work. No problem with kabel. The lever on the motor is turning ok and the axel is also turning but the kluts is not working. Something inside the motor must have got loos. How much of the motor must be taken apart? And to what kost aproximately.