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TM RACING EN Series Workshop Manual

4 stroke engine
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Workshop Manual
4 STROKE ENGINE
250-300
Mx - En - SMx
SMr - SMM - 2016
www.tmracing.it

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Summary of Contents for TM RACING EN Series

  • Page 1 Workshop Manual 4 STROKE ENGINE 250-300 Mx - En - SMx SMr - SMM - 2016 www.tmracing.it...
  • Page 2 TM Racing SPA, declines all liability for any errors in the compilation of this manual, and reserves the right to make any modifications required for the development of its products. Illustrations shown are approximate and, in some cases, may not precisely correspond with the part...
  • Page 3 SMX = COMPETITION SUPERMOTO The displacement, type of power source and type of use define the motorcycle model and engine of each TM Racing motorcycle. The combination of codes 1 and 3 identifies the standard engine type. The combination of the three codes fully identifies the motorcycle model.

  • Page 5: Table Of Contents

    INDEX ADJUSTMENTS/REPLACEMENTS ............7 1.1 Adjusting vAlves plAy (with cold engine) .........8 1.2 cAMshAFts Re-Mounting ..............13 1.3 engine oil And FilteR chAnge .............16 1.4 stAndARd clutch ReplAceMent ............18 1.5 slippeR clutch ReplAceMent ...............20 1.5.1 Disc pack removal ................ 20 1.5.2 discs replacement and re-mounting of clutch ......22 ENGINE DISASSEMBLY................ 27 2.1 engine coMponents lAyout ...............28 2.2 pinion ReMovAl ..................29 2.3 heAd ......................30 2.3.1 head removal ................
  • Page 6 INDEX 2.14 tRAnsMission side counteR geARs.............61 2.15 cRAnKshAFt geAR ReMovAl ..............63 2.16 oil puMp ReMovAl .................64 2.17 geARBoX coMMAnd shAFt ReMovAl ..........65 2.18 RAtchet-holdeR geAR ReMovAl ............66 2.19 seMicAse ....................68 2.19.1 Aperture ..................68 2.19.2 Re-assembly ................. 69 2.20 cRAnKshAFt, geARBoX, geARs dRuM ...........69 2.20.1 components position ..............69 2.20.2 oil filter removal ................69 2.20.3 crankshaft removal ..............69 2.20.4 gear shafts removal ..............
  • Page 7 TECHNICAL SPECIFICATIONS ENGINE TECHNICAL DATA 250Fi-300Fi EN EU4 250Fi-300Fi ENGINE MODEL type 4-stroke single cylinder twin cam, liquid-cooled Displacement 249 cm 291 cm Bore x stroke 77x53.6 mm 81x56.5 mm compression 14: 1 13.7: 1 Fuel Ron 95 unleaded super fuel (ethanol allowed <10%) distribution 4 overhead valve twin cam driven by silenced chain A / s camshafts FA14 / Fs4 FA4 / Fs4 suction valve diameter 32 mm Ti exhaust valve diameter 26.8 mm Ti cold suct. valve play...
  • Page 8 MAINTENANCE MAINTENANCE TABLE • • • change engine oil and cartridge oil filter • clean mesh oil filter • • clean exhaust screw magnet • • • check engine fixing screw tightness • Replace spark plug and cap check • check valve play • check distribution chain • Replace distribution chain • check cylinder and piston wear • Replace piston completely • check head • check camshafts and rocker arms • Replace valves, springs, half cones and plates • Replace piston rod completely • check clutch discs • check clutch springs •...
  • Page 9 TROUBLESHOOTING ENGINE Problem Cause Solution The engine does not start or Insufficient compression struggles to start Replace 1. piston seizing Replace 2. Rod head or foot seizing Replace 3. worn piston segments Replace 4. worn cylinder tighten 5. insufficient cylinder head tightening Replace 6. insufficient head gasket sealing tighten 7. spark plug loosened Adjust 8. incorrect valves play Replace 9.
  • Page 10 TROUBLESHOOTING Problem Cause Solution The shift control pedal 1. selector switch recall spring weakened or broken Replace does not go back into position 2. gear forks worn Replace The gears disengage 1. sliding gears couplings consumed Replace 2. Brake grooves worn Replace 3. housings for couplings on the gears worn Replace 4. grooves on the forks command shaft worn Replace 5. Forks command pins worn Replace INSUFFICIENT ENGINE POWER 1. Air filter dirty clean 2. low fuel quality...

  • Page 11: Adjustments/Replacements

    1. ADJUSTMENTS/REPLACEMENTS...

  • Page 12: Adjusting Valves Play (With Cold Engine)

    ADJUSTMENTS/REPLACEMENTS AdjuSTIng vAlvES PlAy (wITh Cold EngInE) the valve play can be adjusted with the engine mounted on the vehicle or with engine on the bench. noTE: If the engine is mounted on the motorcycle, the airbox must be removed in order to access disassembly of the head cover. For the sake of convenience, the images shown below refer to an engine positioned on a workbench. unscrew the screws (1) from the head cover (2). Remove the cover (2) with the relative gasket (3). if not already performed, remove the spark plug (4).
  • Page 13 ADJUSTMENTS/REPLACEMENTS Mount a comparator (5) on the head. Remove the cap (6) from the generator cover (7). position the gearbox in neutral. using a socket wrench (8), turn the crankshaft to position the piston at top dead centre, as indicated by the timing lines (9) parallel to the edge of the head present on the intake (10) and exhaust (11) camshaft gear and from the comparator (5). Remove the comparator (5).
  • Page 14 ADJUSTMENTS/REPLACEMENTS check that the cams (12) are in rest position; the concave part must be positioned at approx. 45° from the head surface. use a thickness gauge (13) to check the play between the intake camshaft (10) and the valve pad is 0.15mm (0.006 in.). use a thickness gauge (14) to check the play between the exhaust camshaft (11) and the valve pad is 0.20 mm (0.008 in.). otherwise the pads positioned on the valve stem head must be replaced, as follows: loosen the central screw (15) and remove the spring (16) with the pin (17).
  • Page 15 ADJUSTMENTS/REPLACEMENTS unscrew the two screws (18) and remove the chain tensioner (19). tighten the screws (20) of the intake camshaft clamps (21) and remove them. tighten the screws (22) of the exhaust camshaft clamps (23) and remove them. noTE: The intake clamps are marked with "A" embossed on the clamp itself. The exhaust clamps are marked with "S" embossed on the clamp itself.
  • Page 16 ADJUSTMENTS/REPLACEMENTS First remove the intake camshaft (10) and the then exhaust camshaft (11). noTE: support the chain (27) so that it doesn't fall inside the engine. Mark the pads removed even if they are not to be replaced, so that they can be re-mounted in the exact same position. lift the rockers (28) and remove the pads (29).

  • Page 17: Camshafts Re-Mounting

    ADJUSTMENTS/REPLACEMENTS CAMShAFTS RE-MounTIng Mount a comparator (5) on the head and position the piston at top dead centre, rotating the crankshaft via the closed-end spanner (8). noTE: Before re-mounting the camshafts, check that the bearings, gears and chain are not worn and replace if necessary. Retrieve the timing chain (27) and mount the exhaust camshaft (11) first, followed by the intake camshaft (10), taking care to make sure that the timing lines (9) are parallel with the head's upper surface. noTE: For re-mounting, tilt both the camshafts after having positioned the chain (27) and re-position them on the relative housing.
  • Page 18 ADJUSTMENTS/REPLACEMENTS insert the camshafts bearing safety washer (25) into the relative housing. Mount the camshafts clamps (21) and (23), making reference to the embossing present on the same: intake shaft clamps marked with “A”. exhaust shaft clamps marked with “s”. screw the screws (20) and (22) without tightening them and then check that the clamps are correctly placed at the bearings of the camshafts; tighten the screws with a torque of 12 nm (1.2 kgm, 8.85 ft/lb). press the block (30) and push the ratchet (31) of the tensioner (19), until it enters into the body. check gasket wear (32) and replace if ruined. Re-mount the tensioner (19), paying attention that the pin (33) is positioned upwards.
  • Page 19 ADJUSTMENTS/REPLACEMENTS tighten the two screws (18) with a torque of 10 nm (1.0 kgm/ 7.23 ft/lb) insert the pin (17) and the spring (16) inside the chain tensioner (19) and then tighten the screw (15) fully home. noTE: Before tightening the screw (15), check that the aluminium washer (34) is not ruined, replace if necessary. check that valves play is correct (see “valves play check” paragraph) spread some “tree Bond 1215” sealing paste onto the surfaces of the two crescents (35). check that the gasket (3) is not ruined, otherwise replace it, and then position it on the head. Mount the head cover (2) by screwing the screws (1) crosswise and then tightening them with a torque of 8 nm (0.8 kgm/ 5.9 ft/lb).

  • Page 20: Engine Oil And Filter Change

    ADJUSTMENTS/REPLACEMENTS EngInE oIl And FIlTER ChAngE the oil must be changed with the engine off but still warm enough to allow the waste oil to flow out easily. unscrew the four screws (1) and remove the skid plate (2). position the motorcycle on a flat surface and prepare a suitable recipient under the same. loosen the introduction cap (3) positioned on the right side of the engine (clutch cover) and the drain caps (4 and 5) positioned on the lower side of the engine; allow the oil to flow out into the recipient. in the meantime, remove the filter cover (6) situated on the right side of the engine, loosening the relative screws (7) and paying attention to collect the oil escaping.
  • Page 21 ADJUSTMENTS/REPLACEMENTS extract the cartridge filter (8) and clean the surfaces of the guard and filter cover, check the seal o-rings (9 and 10) and replace them if necessary. insert the original new tM Racing filter in a way to have the open side towards the outside of the engine. the filter must be inserted completely into its housing. Re-mount the o-rings and the filter cover, tightening the screws (7) to 8 nm (0.8 kgm, 5.9 ft/lb). wait for the oil to drain completely through the holes, clean the sealing surfaces, replace the aluminium washers, remove any magnetic debris (11) of the draining caps (4 and 5) and screw the caps back on, tightening to 20 nm (2 kgm, 14,75 ft/lb). prepare a measure with the amount of the prescribed engine oil necessary (see table) and pour from the introduction hole. Repeat the oil level check operation.

  • Page 22: Standard Clutch Replacement

    ADJUSTMENTS/REPLACEMENTS STANDARD CLUTCH REPLACEMENT drain the engine oil as described in the relative paragraph. unscrew the M5-l65 (1) and M5-l25 (2) screws, then remove the clutch cover (3). Remove the gasket (4). unscrew the screws (5) of the clutch pack. Remove the spring (6) and the pressure plate (7). Remove the discs (8).
  • Page 23 ADJUSTMENTS/REPLACEMENTS check that the pressure plate (9) is present. noTE: on re-mounting the new discs, lubricate them with engine oil and make sure that the first disc mounted is lined, and that the first two smooth discs have thickness of 1.8 mm (the other discs have thickness of 1.5 mm). Remount the pressure plate (7) with the relative springs (6).

  • Page 24: Slipper Clutch Replacement

    ADJUSTMENTS/REPLACEMENTS SLIPPER CLUTCH REPLACEMENT 1.5.1 disc pack removal drain the engine oil as described in the relative paragraph. unscrew the M5-l65 (1) and M5-l25 (2) screws, then remove the clutch cover (3). tighten the columns (4) supplied. loosen the screws (5) and remove the springs (6). Remove the upper plate (7).
  • Page 25 ADJUSTMENTS/REPLACEMENTS Remove the pressure plate (8). unscrew the nut (9). Remove the nut (9) and the washer (10). Remove the complete clutch pack (11).

  • Page 26: Discs Replacement And Re-Mounting Of Clutch

    ADJUSTMENTS/REPLACEMENTS unscrew the columns (4) and remove the upper drum (4a). extract the disk pack (5). 1.5.2 discs replacement and re-mounting of clutch Mark the position of the arrow (12) on the lower drum (13), which must coincide with the position of the arrow embossed on the upper drum of the clutch pack.
  • Page 27 ADJUSTMENTS/REPLACEMENTS noTE: on re-mounting the new discs, lubricate them with engine oil and make sure that the first disc mounted is lined, and that the first two smooth discs have thickness of 1.5 mm (the other discs have thickness of 2 mm). the clutch pack must finish with a smooth disc.
  • Page 28 ADJUSTMENTS/REPLACEMENTS Mount the disk pack (17) on the lower drum (13). Mount the upper drum (4a), making the arrow (18) coincide with arrow (12) of the lower drum and then tighten the columns (4). Mount the clutch pack (11).
  • Page 29 ADJUSTMENTS/REPLACEMENTS insert the safety washer (10) and the nut (9). tighten the nut (9) with a torque of 100 nm/ 10 kgm/ 73.75 ft/lb + loxeal 82-33. Mount the pressure plate (8). Mount the upper plate (7).
  • Page 30 ADJUSTMENTS/REPLACEMENTS Mount the screw (5) with the relative springs (6) and bushes (18). tighten the screws (5) with a torque of 8 nm (0.8 kgm/ 5.9 ft/lb). Remove the columns (4) supplied. Mount the clutch guard (3) and relative gasket and tighten the screws (1) and (2) gradually with a torque of 8 nm (0.8 kgm/ 5.9 ft/lb). introduce oil into the engine oil as described in the relative paragraph.

  • Page 31: Engine Disassembly

    2. ENGINE DISASSEMBLY...

  • Page 32: Engine Components Layout

    ENGINE DISASSEMBLY ENGINE COMPONENTS LAYOUT Cylinder head cover Cylinder head Chain tensioner Cylinder Starter motor Throttle body connection coupling Temperature sensor Transmission cover oil filter water pump Ignition cover gear sensor Clutch actuator...

  • Page 33: Pinion Removal

    ENGINE DISASSEMBLY PINION REMOvAL Remove the clutch actuator with the pinion cover casing, as described in the relative paragraph. Remove the seeger ring (1) and the pinion (2). slide the bushing (3) out. noTE: on re-mounting the bush (3), check the status of the o-ring gasket (4) and replace it if worn. lubricate the bush (3) and the gasket (4) with engine oil before remounting it.

  • Page 34: Head

    ENGINE DISASSEMBLY hEAd 2.3.1 head removal Remove the head cover and the camshafts, as described in the relative paragraphs. loosen the two lateral nuts (1) at the left of the head. loosen the nuts (2) of the head studs. lift the head (3) and remove it.

  • Page 35: Head Dismantling

    ENGINE DISASSEMBLY Remove the gasket (4). 2.3.2 head dismantling noTE: Mark all components in a way to re-mount the exactly in the same place from where they were removed. Retrieve the pads (5). unscrew the screws (6) of the rocker pins. loosen the M4 screw (7) and slide the pin out (8) and retrieve the rockers (9).
  • Page 36 ENGINE DISASSEMBLY using the relevant tool, compress the valves and use a magnet to remove the two half cones (10). noTE: Pay attention not to damage the support surfaces of the gaskets or of the combustion chamber. Make sure that the separator tool is upright, otherwise the valve stem may bend. Remove the tool and remove the double spring (11) and the relative valve (12). noTE: Before sliding the valve out, check that there are no burrs on the stem, so that the valve-guide and relative oil seal are not ruined.
  • Page 37 ENGINE DISASSEMBLY if ruined, remove the oil seal (13), the valve-guide (14), the relative oR gasket (15) and the valve seat (16). noTE: The valve seats and the valves are different regarding intake and exhaust. do not invert. Mark them before disassembling them in order to re-mount them correctly.

  • Page 38: Head Re-Assembly

    ENGINE DISASSEMBLY 2.3.3 head re-assembly if disassembled, re-mount the valve seat (16), the valve-guide (14) and the oR gasket (15) and the oil seal (13). lubricate the components with engine oil. use engine oil to lubricate the valve stem (12) and insert it into the valve- guide, paying attention not to pinch the oil seal (13). Mount the double spring (11) with relative plates (17) and (18). noTE: Pay attention on re-mounting since the upper and lower plates are not the same. using the relevant tool, compress the double spring (11) and insert the two half cones onto the valve stem; release the double spring and remove the tool. check that the half cones are positioned correctly on the stem using a rubber hammer to tap the upper valve stem to position it correctly.
  • Page 39 ENGINE DISASSEMBLY tighten the screws (6), controlling the status of the copper gasket (19). Replace, if ruined (coupling torque 45 nm, 4.5 kgm 33.19 ft/lb) plus loctite 243. Re-mount the pads (5).

  • Page 40: Head Re-Mounting

    ENGINE DISASSEMBLY 2.3.4 head re-mounting Replace the gasket (4) at every disassembly, and then mount it on the cylinder, positioning the centring bushes (20) in correspondence with the two studs (21). insert the head (3) on the studs. tighten the self-locking nuts (2) crosswise, pulling them and blocking them in 3 steps: Step one: tighten them with a torque of 10 nm (1.0 kgm/ 7.23 ft/lb). Step two: tighten with a torque of 30 nm (3 kgm/ 22.12 ft/lb). Step three: tighten with a torque of 45 nm (4.5 kgm/ 33.19 ft/lb). noTE: It is recommended to replace the self-locking nuts (2) to guarantee the head is perfectly sealed.

  • Page 41: Cylinder And Piston

    ENGINE DISASSEMBLY CYLINDER AND PISTON 2.4.1 Cylinder and piston removal Remove the head as described in the relative section. Remove the fixed plate (1), sliding it upwards. Remove the cylinder (2) by sliding it from the stud bolts. Remove the gasket (3). Remove the lock ring (4) of the piston (5) extract the pin (6) and remove the piston (5).

  • Page 42: Strap And Oil Scraper Replacement And Mounting

    ENGINE DISASSEMBLY 2.4.2 Strap and oil scraper replacement and mounting top ring clean the housing (1) of the straps on the piston from any carbon deposits. noTE: Apply engine oil on the straps before mounting them on the piston. Be careful not to scratch the piston when re-mounting. do not widen the straps excessively during mounting, so that they are not damaged.
  • Page 43 ENGINE DISASSEMBLY insert the two centring bushes (5) and the metal gasket (6). insert the cylinder (7) onto the studs (8). Mount the plate (9) in the relative housing. Mount the head as described in the relative section. noTE: If the cylinder has been replaced, the compression must be checked, operating as described in the "Compression check" paragraph. Re-mount the head as described in the relative section.

  • Page 44: Compression Check

    ENGINE DISASSEMBLY 2.4.5 Compression check with replacement of the cylinder, it is necessary to check that the distance between the piston crown and the upper surface of the cylinder is in within correct tolerance. After having mounted the cylinder, insert the relevant spacers (1) and tighten the nuts (2) with a torque of 25 nm 2.5 kgm, 18.43 ft/lb . position the piston at the top dead centre. position the tool (3) with relative micrometer on the upper surface of the cylinder and zero. Move the tip (4) of the micrometer onto the upper flat part of the piston and take the measurement. Correct compression: 250 cc = 0.85 ± 0.05 mm 300 cc = 0.85 ± 0.05 mm if the measurement does not lie within the tolerance established, the metal gasket (6) of the spacer must be purchased as a spare part, suitable to return within tolerance.

  • Page 45: Temperature Sensor Replacement

    ENGINE DISASSEMBLY TEMPERATURE SENSOR REPLACEMENT unscrew the sensor (1) and replace it by tightening a new sensor with torque of 30 nm, 3.0 kgm, 22.12 ft/lb plus three bond 1215 sealant paste. CLUTCH 2.6.1 Clutch actuator removal with relative command unscrew the screws (1) and remove the actuator (2) and the pinion protection (3). unscrew the screw (4) and remove the bracket (5).
  • Page 46 ENGINE DISASSEMBLY noTE: on re-mounting, check the status of the gasket (7), replace it if ruined. slide the clutch rod (8) out.

  • Page 47: Actuator Removal

    ENGINE DISASSEMBLY 2.6.2 Actuator dismantling separate the two parts of the actuator and remove the piston (9). check the conditions of the seal (10) and the oR gasket (11); replace them if ruined. check the status of the oR gaskets (12), and replace if ruined. noTE: on re-mounting, lubricate the gaskets and seal with clutch oil. Re-mount everything, proceeding in the opposite order to disassembly. tighten the screws (1) with a torque of 8 nm 0.8 kgm/ 5.9 ft/lb.

  • Page 48: Gear Sensor

    ENGINE DISASSEMBLY GEAR SENSOR Remove the clutch actuator as described in the relative paragraph. unscrew the two screws (1). use a screwdriver to lever and remove the gears sensor (2). noTE: Re-mount everything in reverse order to disassembly, paying attention to position the cabling (3) of the sensor in the hollow (4).

  • Page 49: Flywheel Removal

    ENGINE DISASSEMBLY FLYWHEEL REMOvAL 2.8.1 Flywheel cover unscrew the M5-l20 screws (1) and M5-l25 screws (2). Remove the flywheel cover (3). Remove the gasket (4). Retrieve the two centring bushes (5). noTE: on re-mounting, check that the two centring bushes (5) are positioned correctly and that the gasket (4) is not ruined, otherwise replace. Tighten the screws (1) and (2) with a torque of 8 nm (0.8 kgm/ 5.9 ft/lb).

  • Page 50: Stator

    ENGINE DISASSEMBLY 2.8.2 Stator disassembly Remove the flywheel cover as described in the relative section. unscrew the screws (1) that secure the stator (2). unscrew the screws (3) and remove the stop plate (4). Remove the stator (2) with the relative cabling. Mounting Re-mount the stator (2), tightening the screws (1) to a torque value of 5 nm (0.5 Kgm - 3.68 ft/lb + loxeal 82-33). Make sure the rubber cap (5) is fitted correctly on the cover and then tighten the two screws (3) of the stop plate (4) with a torque of 4 nm (0.4 kgm, 2.95 ft/lb). 2.8.3 Pick-up unscrew the two screws (1) and remove the pick-up (2). on re-mounting, check that the bushes (3) and the washers (4) are positioned correctly.

  • Page 51: Rotor

    ENGINE DISASSEMBLY 2.8.4 Rotor disassembly Block rotor rotation (1) and use an impact gun to loosen the nut (2) with relative curve washer. screw the extractor (3) onto the thread of the rotor (1) and tighten the screw (4) to detach the rotor (1) from the crankshaft. Remove the complete rotor (1). Retrieve the key (5).
  • Page 52 ENGINE DISASSEMBLY Remove the distribution chain (6). noTE: Check that the distribution chain (6) and the relative gear (7) on the crankshaft are not worn, otherwise replace (refer to the relative paragraph for replacement of the crankshaft). noTE: In order to replace the chain (6), the camshafts must be removed, as described in the relative paragraph.

  • Page 53: Starter Motor

    ENGINE DISASSEMBLY STARTER MOTOR 2.9.1 disassembly Remove the flywheel cover as described in the relative section. Remove the idler (1) with the relative roller bearing cage. Remove the idler (2) with the relative roller bearing cages. unscrew the screw (3) and remove it with the relative washer. unscrew the two starter motor fastening screws (4).
  • Page 54 ENGINE DISASSEMBLY tighten the M5 screw (5) onto the bush (6) and tighten until the bush (6) moves forward. Remove the starter motor (7).

  • Page 55: Re-Assembly

    ENGINE DISASSEMBLY 2.9.2 Re-mounting Make sure the “oR” gaskets (8) are not ruined and, if so, replace them. check the status of the “oR” gasket (9) positioned on the starter motor (7); replace it if ruined. lubricate the gasket (9) and the gaskets (8) with engine oil and then mount the starter motor (7). use an aluminium or brass punch to push the bush (6) towards the inside of the engine, making the milled part coincide (6a) with the screw housing (6b). noTE: If the bush (6) is forced, grease abundantly. tighten the screw (3) with relative washer to a torque value of 6 nm (0.6 Kgm - 4.42 ft/lb) + loxeal 82-33.

  • Page 56: Water Pump

    ENGINE DISASSEMBLY Re-mount the idler (2) with the relative roller bearing cages and lubricating with engine oil. Re-mount the idler (1) with the relative roller bearing cage and lubricating with engine oil. 2.10 WATER PUMP noTE: If water escapes from the little hole (1), the pump seal must be replaced. loosen the screws (2) and (2a) M5-l20, screw (3) M5-l45 and screw (4) M5-l50.
  • Page 57 ENGINE DISASSEMBLY Remove the cover (5) with the relative gasket (6). insert a “t”-shaped wrench (7) through the flywheel cover to block crankshaft rotation. loosen the pump impeller (8). use a screwdriver to remove the seal (9). noTE: lubricate the seal (9) with engine oil before mounting it. Re-mount the impeller (8) tightening with a torque of 6 nm (0.6 kgm/ 4.42 ft/lb), greasing the thread. Re-mount the pump cover (5) checking that the gasket (6) is not ruined; replace it if necessary. tighten the screws (2), (3), (4) with a torque of 8 nm (0.8 kgm/ 5.9 ft/lb), replacing the aluminium washer of the screw (2a).

  • Page 58: Transmission Guard

    ENGINE DISASSEMBLY 2.11 TRANSMISSION GUARD unscrew the screws (1): M5-l25 screw M5-l30 screw M5-l65 screw M5-l45 screw M5-l50 screw Remove the guard (2), with the aid of a rubber hammer. Remove the gasket (3) and recover the two centring bushes (4). Remove the water pump return (5).

  • Page 59: Bearing And Water Pump Oil Seal Removal

    ENGINE DISASSEMBLY 2.11.1 Bearing and water pump oil seal removal heat the bearing to a temperature of 50°c and remove the bearing (6). wARnIng: use suitable personal protection equipment; Burns hazard. Remove the oil seal (7), operating from the external part of the guard with water pump disassembled. noTE: on re-mounting, first mount the bearing (6) and then the seal (7), lubricating it with engine oil. 2.11.2 Seal and oil passage bored disc removal Remove the seeger (8), the seal (9) and the bored disc (10).

  • Page 60: Transmission Cover Re-Assembly

    ENGINE DISASSEMBLY 2.11.4 Transmission cover re-assembly clean the surface of the lid and the semicase from any residues. check that the two centring bushes (4) are in their respective housing. Replace and re-mount the gasket (3). Mount the water pump return (2) on the cover (5). Mount the cover (2), centring it on the bushes (4), paying attention not to ruin the seals.

  • Page 61: Idle Kick Starter Removal (Only K.s.)

    ENGINE DISASSEMBLY tighten the screws (1) crosswise, positioning them in the relative housing, depending on their length. M5-l25 screw M5-l30 screw M5-l65 screw M5-l45 screw M5-l50 screw First screw without tightening with a torque of 8 nm (0.8 kgm/ 5.9 ft/lb). 2.12 IdlE KICK STARTER REMovAl (only K.S.) Remove the transmission cover and the clutch bell as described in the relative paragraphs. Release the spring (1) from the relative housing, turn the starter (2) anti- clockwise by 1/4 of a turn. Remove the starter (2) complete with spring (3) and washer (4). 2.12.1 Starter dismantling in sequence, remove the washer (4), spring (3), bush and ratchets (5), the seeger (6), shim (7), gear (8), shaft (9), bush (10) and the spring (1).

  • Page 62: Re-Assembly

    ENGINE DISASSEMBLY 2.12.2 Re-mounting Re-mount the idle kick start in the relative housing and then turn the starter (2) clockwise by 1/4 of a turn and insert the pin (1) in the hole in the guard. noTE: lubricate the fitting hole abundantly with graphite grease. 2.13 dRuM And CluTCh BEll 2.13.1 disassembly Remove the transmission cover as described in the relative paragraph. Remove the clutch discs as described in the relative paragraph. Remove the clutch mushroom (1). use a spanner to block rotation of the clutch drum (2) and tighten the nut (3). Remove the safety washer (4).
  • Page 63 ENGINE DISASSEMBLY Remove the washer (5). Remove the bell (6). Remove the two roller bearings (7) and the spacer (8). Remove the washer (9). 2.13.2 Re-mounting insert the washer (9). Re-mount everything, proceeding in the reverse order to disassembly.
  • Page 64 ENGINE DISASSEMBLY Make sure that the spacer (8) and ball bearings cage (7) are re-mounted correctly and lubricate them with engine oil. proceed exactly with the reverse procedure. Re-mount the bell (6). insert the washer (5). After having re-mounted the bell (6) and the drum (2), make sure the safety washer (4) has been positioned correctly. screw the nut (3), blocking drum rotation with a spanner, with torque of 100 nm 10.0 kgm 73.75 ft/lb + strong threadlocker (green).

  • Page 65: Transmission Side Counter Gears

    ENGINE DISASSEMBLY 2.14 TRANSMISSION SIDE COUNTER GEARS components layout: oil pump return gear. Idle gear kick starter removal. Kick starter (only for K.S.). gearbox primary shaft. gearbox command shaft. Ratchet-holder gear. oil pump. Crankshaft gear. Remove the seeger (9) and the washer (10). Remove the oil pump return gear (1). Remove the roller bearing cage (11) and the washer (12).
  • Page 66 ENGINE DISASSEMBLY Remove the seeger (13). Remove the shim (14) and the gear (2). Remove the roller bearing cage (15) and the shim (16). noTE: To re-mount the gears and relative roller bearing cages, proceed in reverse order to disassembly and lubricate with engine oil.

  • Page 67: Crankshaft Gear Removal

    ENGINE DISASSEMBLY 2.15 CRANKSHAFT GEAR REMOvAL insert the tool (1) to block rotation of the crankshaft and unscrew the nut (2). Remove the washer (3). Remove the gear (4), recovering the relative key. noTE: on re-mounting the gear (4), tightening the nut (2) to a torque value of 100 nm (10 Kgm - 73.75 ft/lb) + loxeal 82-33. Blocking crankshaft rotation with the relevant tool (1).

  • Page 68: Oil Pump Removal

    ENGINE DISASSEMBLY 2.16 OIL PUMP REMOvAL Remove the clutch bell and the oil pump return gear, as described in the relevant paragraphs. unscrew the screws (1). Remove the pump (2) by lifting it. Recover the two centring bushes (3) and remove the two external sectors (4) and (5). Remove the dragging pin (6).

  • Page 69: Gearbox Command Shaft Removal

    ENGINE DISASSEMBLY Remove the separation plate (7). Remove the two internal sectors (8), (9) and the dragging pin (10). noTE: on re-mounting, lubricate with engine oil and check that the dragging pins are correctly mounted and tighten the screws (1) with torque of 8 nm (0.8 Kgm, 5.79 ft/lb). 2.17 GEARBOX COMMAND SHAFT REMOvAL Remove the transmission guard as described in the relative paragraph. lift the shaft (1) and extract it from the engine.

  • Page 70: Ratchet-Holder Gear Removal

    ENGINE DISASSEMBLY to remove the pin (3) loosen the nut (5) with relative washer (6). noTE: To re-mount, proceed in reverse order to the disassembly operations, paying attention that the spring (2) inserts correctly into the pin ( 7) fixed on the engine guard and that the two timing bolts (8), one on the shaft and the other on the ratchet-holder gear, are aligned.
  • Page 71 ENGINE DISASSEMBLY Remove the plate (3) and the plate (4). lift and remove the Ratchet-holder gear (5). dismantle the ratchets (6) and (7) with the relative tips (8) and springs (9). noTE: on re-mounting, make sure the ratchets (6) and (7) are inserted correctly in the relative housing; they cannot be inverted. Re-mount everything in reverse order to the disassembly operations, checking that the two timing bolts (10), one on the shaft and the other on the ratchet-holder gear, are aligned.

  • Page 72: Semicase

    ENGINE DISASSEMBLY 2.19 SEMICASE Remove the heating unit as described in the relevant paragraph. Remove all parts on the flywheel side and transmission side as described in the relative paragraphs. 2.19.1 Aperture unscrew the screws (1): M6-l55 screw M6-l35 screw use a rubber hammer to open the two semicases (2) and (3). Retrieve the two bushes (4) and (5). noTE: There is a lamella (6) positioned on the semicase (2); loosen the screws (7) to remove it.

  • Page 73: Re-Assembly

    ENGINE DISASSEMBLY 2.19.2 RE-ASSEMBLY check that all components are correctly positioned in their housing and that the centring bushes (4) and (5) are mounted. clean the contact surface from any residual sealant paste and then spread a treebond type sealing paste. Re-position the screws (1) in the relative housing depending on their length and tighten them with torque of 12 nm (1.2 kgm, 8.68 ft/lb): M6-l55 screw M6-l35 screw 2.20 CRAnKShAFT, gEARBoX, gEARS dRuM open the guards as indicated in the relative section. 2.20.1 COMPONENTS POSITION Crankshaft gearbox primary shaft gearbox secondary shaft gears selector drum Ratchet Mesh oil filters...

  • Page 74: Gear Shafts Removal

    ENGINE DISASSEMBLY 2.20.4 gear shafts removal extract the secondary shaft fork pin (7). Release the forks (8) and (9) of the secondary shaft from the selector drum and remove them. slide the primary shaft fork pin (10) out. Remove the complete gear assy (11) with the fork (12) inserted.

  • Page 75: Primary Shaft, Gear Sequence

    ENGINE DISASSEMBLY 2.20.5 Primary shaft, gear sequence Primary shaft First Fifth Third Fourth Sixth Second 2.20.6 Secondary shaft, gear sequence Primary shaft First Fifth Third Fourth Sixth Second 2.20.7 gears drum removal use a screwdriver to move the ratchet (5), releasing the drum (4), and then remove the drum from the semicase. 2.20.8 Ratchet removal unscrew the screw (13) and remove the ratchet (5) with the relative spring (14).

  • Page 76: Bearings Replacement

    ENGINE DISASSEMBLY 2.20.9 Bearings replacement unscrew the screws (1) that block the crankshaft bearing (2) and remove the plates (3). unscrew the screw (4) with relative primary shaft bearing safety washer (5). heat the guards and remove the bearings. noTE: After having replaced the bearings, re-position the safety washers and tighten the screws again and applying loxeal 82-33 on the thread. 2.20.10 Components re-mounting Re-mount the components, proceeding in reverse order to disassembly, lubricating with engine oil and, when re-mounting the gearbox unit, paying attention to correctly position the forks (7) and (10) in the relevant positions:...

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