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Suzuki EN125-2A Service Manual

Summary of EN125-2A

  • Page 1

    Service manual 99500h06100-01e en125-2a.

  • Page 2

    Prepared by customer service department 1st ed. Aug, 2003 part no.:99500h06100-01e printed in china jiang men dachangjiang group co., ltd..

  • Page 3: Foreword

    The suzuki en125-2a was designed to offer superior performance through light weight design and four stroke power. The new en125-2a represents another major advance by suzuki in four stroke motorcycles. This service manual has been produced primarily for experienced mechanics whose job is to inspect,...

  • Page 4: Group Index

    Group index 1 general information 2 3 4 5 6 7 periodic maintenance and break-in procedures engine fuel and lubrication system electrical system chassis servicing information.

  • Page 6: General Information

    General information contents serial number locations fuel and oil recommendations break-in procedure special feature special materials specifications 1-2 1-2 1-2 1-3 1-4 1-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

  • Page 7: Warning/caution/note

    1-1 general information warning/caution/note please read this manual and follow its instructions carefully. To emphasize special information, the symbol and the words warning, caution and note have special meanings. Pay special attention to the messages highlighted by these signal words. Warning: pe...

  • Page 8

    The frame serial number is stamped on the steering head pipe. The engine serial number is located on the crankcase. These numbers are required especially for registering the machine and ordering spare parts. Ù serial number locations use gasoline with an octane number of 90 97 or higher (research me...

  • Page 9

    Transistorized ignition system with electronic advance description special feature 200 100 o o 2 4 6 8 10 engine r/min (x 1000 r/min) fig.2 closing angle (degree) 1.0 0.5 2 4 6 8 10 engine r/min (x 1000 r/min) fig.3 electric current (a) on the model en125-2a, the timing advance characteristics of th...

  • Page 10

    The materials listed below are needed for maintenance work on the en125-2a and should be kept on hand for ready use. These items supplement such standard materials as cleaning fluids, lubricants, emery cloth and the like. How to use them and where to use them are described in the text of this manual...

  • Page 11: Specifications

    1-5 general information specifications dimensions and dry mass engine transmission overall length overall width overall height wheelbase ground clearance seat height dry mass type number of cylinders bore stroke piston displacement compression ratio carburetor air cleaner starter system lubrication ...

  • Page 12

    General information 1-6 electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....

  • Page 13: Periodic Maintenance And

    Periodic maintenance and tune-up procedures contents periodic maintenance schedule maintenance procedures battery cylinder head nuts, cylinder nuts, exhaust pipe bolts and nuts air cleaner element valve clearance compression pressure spark plug fuel hose fuel filter engine oil engine oil filter oil ...

  • Page 14

    2-1 periodic maintenance and tune-up procedures periodic maintenance schedule the chart below lists the recommended intervals for all the required periodic service work necessary to keep the motorcycle operating at peak performance and economy. Note: more frequent servicing may be performed on motor...

  • Page 15

    Periodic maintenance and tune-up procedures 2-2 periodic lubrication chart the maintenance schedule, which follows, is based on this philosophy. It is timed by odometer indication, and is calculated to achieve the ultimate goal of motorcycle maintenance in the most economical manner. Throttle cable ...

  • Page 16: Maintenance Procedures

    2-3 periodic maintenance and tune-up procedures this section describes the service procedures for each section of periodic maintenance. Maintenance procedures for checking specific gravity, use a hydrometer to determine the charged condition. Battery inspect initial 1 000 km and every 4 000 km the b...

  • Page 17

    Periodic maintenance and tune-up procedures 2-4 remove the seat and fuel tank (refer to page 3-2) remove the right and left caps of the cylinder head cover after remove the tachometer cable ( ). Remove the cylinder head cover (refer to page 3-8) tighten the four 10mm nuts and two 6-mm nuts to the sp...

  • Page 18

    2-5 periodic maintenance and tune-up procedures fill a washing pan of a proper size with nonflammable cleaning solvent. Immerse the element in the cleaning solvent and wash it clean. Squeeze the cleaning solvent out of the washed element by pressing it between the palms of both hands. Immerse the el...

  • Page 19

    Periodic maintenance and tune-up procedures 2-6 excessive valve clearance results in valve noise and insufficient valve clearance results in valve damage and reduced power. At the distances indicated above, check and adjust the clearance to the following specification. The procedure for adjusting th...

  • Page 20

    2-7 periodic maintenance and tune-up procedures remove the carbon deposits with a wire or pin and adjust the spark plug gap to 0.7-0.8 mm, measuring with a thickness gauge. When removing carbon deposits, be sure to observe the appearance of the plug, noting the color of the carbon deposits. The colo...

  • Page 21

    Periodic maintenance and tune-up procedures 2-8 inspect the fuel hose and connections for damage and fuel leakage. If any defects are found, the fuel hose must be replaced. Fuel hose inspect initial 1 000 km and every 4 000 km replace every four years. If the fuel filter is dirty with sediment, fuel...

  • Page 22

    2-9 periodic maintenance and tune-up procedures note: pour about 1,150 ml of engine oil into the engine only when changing oil and replacing oil filter at the same time. When performing engine overhaul, the amount of oil to be replenished is 1,350 ml. Engine oil filter replace initial 1 000 km and e...

  • Page 23

    Periodic maintenance and tune-up procedures 2-10 loosen the lock nut and screw the adjuster on the clutch lever holder all the way in. Loosen clutch cable adjuster lock nut . Turn the clutch cable adjuster in or out to acquire the specified play. Tighten lock nut while holding the adjuster in carbur...

  • Page 24

    2-11 periodic maintenance and tune-up procedures drive chain inspect and clean every 1 000 km drive chain visually inspect the drive chain for the below listed possible malconditions. (lift the rear wheel by placing the center stand, and turn the rear wheel slowly by hand when the transmission in ne...

  • Page 25

    Periodic maintenance and tune-up procedures 2-12 support the motorcycle body on the center stand, and place the handlebars straight. Check the brake fluid level by observing the lower limit line on the brake fluid reservoir. When the level is below the lower limit line, replenish with brake fluid th...

  • Page 26

    2-13 periodic maintenance and tune-up procedures air bleeding the brake fluid circuit air trapped in the fluid circuit acts like a cushion to a b s o r b a l a r g e p r o p o r t i o n o f t h e p r e s s u r e developed by the master cylinder and thus interferes with the full braking performance o...

  • Page 27

    Periodic maintenance and tune-up procedures 2-14 rear brake bring the brake pedal to a position about 10 mm (behind the frame). This is effected by turning the brake pedal stopper after remove the two screws and take off the right cover. Be sure to tighten the lock nut securely after setting the bol...

  • Page 28

    2-15 periodic maintenance and tune-up procedures tires inspect initial 1 000 km and every 4 000 km tire inspect the tires for wear and damage; and check the tire tread depth as shown. Replace a badly worn or damaged tire. A tire with its tread worn down to the limit (in terms of tread depth) must be...

  • Page 29

    Periodic maintenance and tune-up procedures 2-16 steering inspect initial 1 000 km and every 4 000 km steering stem bearings be adjusted properly for smooth turning of the handlebars and safe running. Steering which is too stiff prevents smooth movement of handlebars. Steering which is too loose wil...

  • Page 30

    2-17 periodic maintenance and tune-up procedures chassis and engine mounting bolts and nuts inspect initial 1 000 km and every 4 000 km the nuts and bolts listed are important parts, and they must be in good condition for safety. They must be retightened, as necessary, to the specified torque with a...

  • Page 31

    Periodic maintenance and tune-up procedures 2-18 7 6 6 8 9 b b a.

  • Page 32: Engine

    Engine contents 3-1 3-2 3-7 3-12 3-23 3-30 3-38 3-42 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....

  • Page 33

    3-1 engine compression pressure and oil pressure compression pressure remove spark plug. Fit the compression gauge and adapter to the plug hole, taking care to make the connection absolutely tight. Twist the throttle grip into wide-open position. Crank the engine several times with the starter motor...

  • Page 34

    Before taking the engine out of the frame, thoroughly clean the engine with a suitable cleaner. The procedure of engine removal is sequentially explained in the following steps. Take off the right and left frame covers. Disconnect the and lead wires of battery. Engine 3-2 enging removal and remounti...

  • Page 35

    3-3 engine take off the clutch cable by removing the clutch lever bolt and adjuster lock nut. Take off the breather pipe. Loosen the throttle cable adj ster lock nuts, and take off the throttle cable. U remove the carburetor by unscrewing the clamp screws. Disconnect the couplers of generator and ge...

  • Page 36

    Engine 3-4 remove gear shift lever. Take off the engine sprocket cover. Disconnect the lead wire of starter motor. Take off the spark plug cap. Take off the drive chain by removing the clip. Disconnect the ground wire from the crankcase. Direction of travel.

  • Page 37

    3-5 engine remove the tachometer cable. Take off the left and right caps of the cylinder head cover. Remove the exhaust pipe nuts and muffler mounting bolt, then take off the muffler. Remove engine mounting bolts, swing arm pivot nut, footrest bar bolts and brackets. Use both hands, and lift the eng...

  • Page 38

    The engine can be mounted in the reverse order of removal. Temporarily fasten the engine mounting bracket before inserting the engine mounting bolts. Engine 3-6 engine remounting note: the engine mounting nuts are self-lock nuts. Once the nut has been removed, it is no longer of any use. Be sure to ...

  • Page 39

    3-7 engine upper end components disassembly cylinder head cover and cylinder head drain engine oil. Note: if top end repair only is being performed, it is not necessary to remove the engine from the frame. As already noted, seat, fuel tank, frame covers etc. Must be removed. * * remove magneto cover...

  • Page 40

    Engine 3-8 bring the piston to top dead center. First, remove the tachometer sleeve securing screw, and then pull out the tachometer driven gear shaft with sleeve. Next, loosen the cylinder head cover bolts in the order indicated in the illustration and remove detach the cylinder head cover. Bracket...

  • Page 41

    3-9 engine remove rocker arm shaft set bolts. Pull out the rocker arm shafts with pliers. Remove cylinder base nuts and cylinder. Caution: if tapping with plastic hammer is necessary. Do not break the fins..

  • Page 42

    Engine 3-10 compress the valve spring by using the special tool. Valve lifter 09916-14510 take off the valve cotters from valve stem. Tweezers 09916-84510 take out the valve spring retainer, inner spring and outer spring. Pull out the valve from the other side. Remove oil seal, using long-nose plier...

  • Page 43

    3-11 engine remove valve guide by using the special tool. Valve guide remover 09916-44910 caution: only oversize valve guide is available as a spare part. Place a clean rag over the cylinder base to prevent piston pin circlip from dropping into crankcase and then, remove the piston pin circlip with ...

  • Page 44

    Engine 3-12 upper end components inspection and servicing after removing sealant (suzuki bond no.1215) from the fitting surface of the cylinder head cover, place the cylinder head cover on a surface plate and check for distortion with a thickness gauge. Check points are shown in fig. Service limit 0...

  • Page 45

    3-13 engine camshaft cam wear worn-down cams are often the cause of mistimed valve operation resulting in reduced output power. The limit of cam wear is specified for both intake and exhaust cams in terms of cam height , which is to be measured with a micrometer. Replace camshafts if found it worn d...

  • Page 46

    Engine 3-14 note: visually inspect each valve for wear of its seating face. Replace any valve with an abnormally worn face. Cylinder head distortion decarbon combustion chamber. Check the gasketed surface of the cylinder head for distortion with a straightedge and thickness gauge, taking a clearance...

  • Page 47

    3-15 engine re-finish the valve guide holes in cylinder head with a 10.8 mm reamer and handle. Caution: this remedy is permissible where the length will not be reduced to less than 2 mm. If this length becomes shorter than 2 mm, then the valve must be replaced. After installing the valve whose stem ...

  • Page 48

    Engine 3-16 5.0 mm reamer 09916-34570 reamer handle 09916-34542 after fitting all valve guides, re-finish their guiding bores with a 5.0 mm reamer. Be sure to clean and oil the guides after reaming. Install valve spring lower seat . Be careful not to confuse the lower seat with the spring retainer ....

  • Page 49

    3-17 engine valve seat width coat the valve seat with prussian blue uniformly. Fit the valve and tap the coated seat with the valve face in a rotating manner, in order to obtain a clear impression of the seating contact. In this operation, use the valve lapper to hold the valve head. The ring-like d...

  • Page 50

    Engine 3-18 caution: cut the minimum amount necessary from the seat to prevent the possibility of the valve stem becoming too close to the rocker arm for correct valve contact angle. After the desired seat position and width is achieved, use the 45 cutter very lightly to clean up any burrs caused by...

  • Page 51

    3-19 engine valve springs check the springs for strength by measuring their free lengths and also the force required to compress them. If the limit indicated below is exceeded by the free length reading or if the measured force does not fall within the range specified, replace with a new spring as a...

  • Page 52

    Engine 3-20 piston diameter using a micrometer, measure the piston outside diameter at the place 10 mm from the skirt end as shown in fig. If the measurement is less than the limit, replace the piston. Piston ring-groove clearance micrometer (50 75 mm) 09900-20203 service limit 56.880 mm note: using...

  • Page 53

    3-21 engine before installing piston rings, measure the free end gap of each ring using vernier calipers. Next, fit the ring in the cylinder, and measure each ring end gap using a thickness gauge. If any ring has an excess end gap, replace the ring. Thickness gauge 09900-20803 piston ring service li...

  • Page 54

    Engine 3-22 piston pin and pin bore using a caliper gauge, measure the piston pin bore inside diameter, and using a micrometer measure the piston pin outside diameter. If the difference between these two measurements is more than the limits, replace both piston and piston pin. Micrometer (0 25 mm) 0...

  • Page 55

    3-23 engine top ring and 2nd ring install spacer into the bottom ring groove first. Then install both side rails , one on each side of the spacer. The spacer and side rails do not have a specific top or bottom when they are new. When reassembling used parts. Install them in their original place and ...

  • Page 56

    Engine 3-24 the following are reminders for piston installation: piston rub a small quantity of suzuki moly paste onto the piston pin. Place a clean rag over the cylinder base to prevent piston pin circlip from dropping into crankcase, and then fit the piston pin circlip with long-nose pliers. Cauti...

  • Page 57

    3-25 engine valve and spring insert the valves, with their stems coated with suzuki moly paste all around and along the full stem length without any break. Similarly oil the lip of the stem seal. Install valve springs, making sure that the close-pitch end of each spring goes in first to rest on the ...

  • Page 58

    Engine 3-26 cylinder head fit dowel pins to cylinder head and then, attach new gasket to cylinder head. Copper washers and cap nuts are used to secure the cylinder head. Caution: use a new cylinder head gasket to prevent oil leakage. Do not use the old gasket. With the head snugly seated on the cyli...

  • Page 59

    3-27 engine camshaft align the mark on magneto rotor with the index mark on the crankcase keeping the camshaft drive chain pulled upward. Caution: if crankshaft is turned without drawing the camshaft drive chain upward. The chain will be caught between crankcase and cam chain drive sprocket. Align t...

  • Page 60

    Engine 3-28 bend up he washer tongue positively to lock the bolts. Apply suzuki moly paste to the camshaft journal and place camshaft on cylinder head. Suzuki moly paste 99000-25140 valve rocker arm and shaft apply suzuki moly paste to the rocker arms and shafts. Place the spring and the wave washer...

  • Page 61

    3-29 engine cylinder head cover thoroughly wipe off oil from the fitting surfaces of cylinder head. Fit the two dowel pins to the cylinder head side. Uniformly apply suzuki bond no.1215 to the cylinder head surface. Suzuki bond no.1215 99000-31110 note: do not apply suzuki bond no.1215 to the camsha...

  • Page 62

    Engine 3-30 lower end components disassembly magneto rotor remove magneto cover bolts and detach magneto cover. Loosen and remove the starter motor mounting bolts. Take off the starter motor. Remove the starter idle gear. Remove magneto rotor nut. Rotor holder 09930-44511 note: do not allow camshaft...

  • Page 63

    3-31 engine remove magneto rotor and key. Rotor remover attachment 09930-30180 slide shaft 09930-30102 remove starter clutch gear. Remove cam drive chain. Remove roller , spring and push piece from starter clutch. Clamp the rotor with a vise taking care not to damage it and remove the three allen bo...

  • Page 64

    Engine 3-32 clutch remove clutch cover bolts and oil filter cap bolts, and detach clutch cover by tapping with a plastic hammer. R e m o v e c l u t c h s p r i n g m o u n t i n g b o l t s diagonally while holding the primary driven gear, and remove clutch pressure plate. Conrod holder 09910-20116...

  • Page 65

    3-33 engine flatten the lock washer, then remove the nut, lock washer and oil pump drive gear. Caution: this is a left-hand thread nut. Remove oil pump driven gear, then remove primary drive gear and key. Oil pump remove oil pump mounting screws and take off oil pump body. Note: when removing cam dr...

  • Page 66

    Engine 3-34 drive shaft retainer remove the drive shaft retainer circlip by using snap ring pliers. Snap ring pliers 09900-06107 note: when removing gear position switch, do not lose contact and spring. Remove gear position switch. Gear position switch engine sprocket flatten the lock washer, then r...

  • Page 67

    3-35 engine remove sump filter. Remove crankcase securing bolts. Caution: t h e c r a n k s h a f t a n d t r a n s m i s s i o n components must remain in the left crankcase half. This is necessary because the gear shifting cam stopper is mounted on the left crankcase half and will be damaged if th...

  • Page 68

    Engine 3-36 transmission remove gear shifting cam stopper spring. Draw out gear shifting fork shafts and take off forks. Remove clusters of gears and gear shifting cam. Crankshaft remove crankshaft by using crankshaft rem ver. O crankshaft remover 09920-13120

  • Page 69

    3-37 engine oil seal and bearing remove retainers, oil seals and bearings. Oil seal remover bearing puller 09913-50121 09923-73210 bearing installer 09940-53311 09924-84510 09913-75820 09913-80112.

  • Page 70

    Engine 3-38 service limit 3.0 mm lower end components inspection and servicing conrod deflection and conrod big end side clearance wear on the big end of the conrod can be estimated by checking the movement of the small end of the rod. This method can also check the extent of wear on the parts of th...

  • Page 71

    3-39 engine clutch drive plate measure the thickness and claw width of each drive plate with vernier calipers. Replace drive plates found to have worn down to the limit. Vernier calipers 09900-20101 item thickness claw width standard 2.9 3.1 mm 11.8 12.0 mm limit 2.6 mm 11.0 mm clutch driven plate m...

  • Page 72

    Engine 3-40 clutch release bearing inspect the release bearing for any abnormality, particularly cracks, to decide whether it can be reused or should be replaced. Smooth engagement and disengagement of the clutch depends much on the condition of this bearing. Shifting fork and gear using a thickness...

  • Page 73

    3-41 engine primary driven gear primary dr ven gear is composed as shown. I Ù primary driven gear damper plate rivet clutch housing if the internal damper wears, play is generated between gear and housing, causing abnormal noise. If the play is extreme, replace the primary driven gear assembly with ...

  • Page 74

    Engine 3-42 decide the width between the webs referring to the figure below when rebuilding the crankshaft. Std width between webs 53.0 0.1 mm lower end components reassembly crankshaft when mounting the crankshaft in the crankcase, it is necessary to pull its left end into the crankcase. Crankshaft...

  • Page 75

    3-43 engine caution: never fit the crankshaft into the crankcase by striking it with a plastic hammer. Always use the special tool, otherwise crankshaft alignment accuracy will be affected. Transmission caution: never reuse a circlip. After a circlip has been removed from a shaft, it should be disca...

  • Page 76

    Engine 3-44 note: when reassembling the bearing retainer, apply a small quantity of thread lock "1342" to the threaded parts of the bearing retainer screws. In reassembling the transmission, attention must be given to the locations and positions of washers and circlips. The cross sectional view give...

  • Page 77

    3-45 engine fit the gear shifting cam on the crankcase. Position the cam as shown in fig. So that the gear shifting fork can be installed easily. Gear shifting cam and fork.

  • Page 78

    Engine 3-46 note: two kinds of gear shifting forks, and are used. They resemble each other very closely in external appearance and configuration. Carefully examine the illustration for correct installing positions and directions. Ù after cam stopper and gear shifting forks have been fitted, hook cam...

  • Page 79

    3-47 engine crankcase coat suzuki super grease "a" to the lip of oil seals. Remove sealant material on the fitting surfaces of right and left halves of crankcase and thor- oughly remove oil stains. Fit dowel pins on the left half. Apply engine oil to the big end of the crankshaft conrod and all part...

  • Page 80

    Engine 3-48 gear shifting cam driven gear when installing the gear shifting pawls into the cam driven gear. The large shoulder must face to the outside as shown. A thread lock "1342" 99000-32050 next, install cam guide and pawl lifter, apply a small quantity of thread lock "1342" to the threaded par...

  • Page 81

    3-49 engine thread lock "1342" 99000-32050 before mounting the oil pump, apply engine oil to the sliding surfaces of the case, outer rotor, inner rotor and shaft. Apply a small quantity of thread lock "1342" to the threaded parts of oil pump mounting screws. Tighten the oil pump mounting screws. Not...

  • Page 82

    Engine 3-50 clutch install the clutch camshaft by positi ning the face to right side. Install the oil seal by using the 17 mm socket. O tighten the oil seal retainer screw. 1.5 mm 2.0 mm.

  • Page 83

    3-51 engine assemble the clutch, in the reverse order of disassembly. Pay attention to the following points. When inserting spacer on countershaft, apply a small quantity of engine oil to both inside and outside of the spacer. Tighten clutch sleeve hub nut using the special tool to the specified tor...

  • Page 84

    Engine 3-52 loosen the lock nut, and turn in the release screw to feel high resistance. From that position, turn out the release screw 1/4 1/2 turn, and tighten the lock nut. - clutch release screw adjustment when reassembling the clutch cover, fit a gasket to correctly position as shown in fig. Cau...

  • Page 85

    3-53 engine starter clutch thread lock super "1303b" 99000-32030 "t" type hexagon wrench (5 mm) 09911-73730 tightening torque apply thread lock super "1303b" to allen bolts and tighten with specified torque. 15 20 n m (1.5 2.0 kg m) - - magneto rotor fit key in the key slot on the crankshaft. Instal...

  • Page 86

    Engine 3-54 starter idle gear and motor install the starter idle gear. Install the starter motor. Driveshaft oil seal and engine sprocket caution: always replace the driveshaft oil seal with a new one every disassembly to prevent oil leakage. Also grease the oil seal lip. On installation, refer to f...

  • Page 87

    3-55 engine 09930-40113 tightening torque tighten the engine sprocket nut to the specified torque and bend up the washer. 80 100 n m (8.0 10.0 kg m) - - rotor and sprocket holder gear position switch install gear position switch. Thread lock super "1303b" 99000-32030 apply thread lock super "1303b" ...

  • Page 88

    Fuel and lubrication system contents 4-1 4-2 4-6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....

  • Page 89: Fuel Cock

    4-1 fuel and lubrication system fuel cock turn fuel cock to "off" position and discon- nect fuel line from the fue cock. L place a clean oil pan under the fuel cock assembly, turn fuel cock to "on" position and drain the fuel. Unscrew the fuel cock securing bolts, and take off the fuel cock assembly...

  • Page 90: Carburetor

    Fuel and lubrication system 4-2 carburetor carburetor construction item item specification specification 12.5 37.5 pre-set (2,5/8 turn out) 1.25 0.5-1.0 4dh41-2nd p-0 (390) £ £ needle jet (n.J.) pilot jet (p.J.) starter jet (g.S) pilot screw (p.S.) pilot air jet (p.A.J.) throttle cable play jet need...

  • Page 91

    Take off the carburetor (refer to page 3-2and 3) remove the carburetor top cover by unscrewing the cover screws. . Removal and disassembly remove the float chamber body by unscrewing the two screws. Loosen the fitting screw and remove the float. 4-3 fuel and lubrication system remove the throttle va...

  • Page 92

    Remove the needle valve retainer and needle valve. Remove the main jet. Remove the needle jet. Remove the pilot jet. Fuel and lubrication system 4-4 remove the main air jet. If foreign matter is caught between the valve seat and the needle, the gasoline will continue flowing and cause it to overflow...

  • Page 93

    4-5 fuel and lubrication system loosen the lock nuts . Slide the adjuster to obtain the correct play 0.5 1.0 mm. - r e m o u n t t h e c a r b u r e t o r b y r e v e r s i n g t h e s e q u e n c e o f r e m o v a l s t e p s , a n d f o l l o w i n g adjustments and inspection are necessary after ...

  • Page 94: Lubrication System

    Fuel and lubrication system 4-6 lubrication system camshaft journal and cam face rocker arm shaft cam chaim conrod small end cylinder wall conrod big end bearing clutch release cam driveshaft bearing driveshaft and gears contershaft bearing countershaft and gears primary driven gear spacer clutch pl...

  • Page 95

    4-7 fuel and lubrication system.

  • Page 96: Chassis

    Chassis contents 5-1 5-6 5-12 5-21 5-27 5-35 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....

  • Page 97

    5-1 chassis front wheel tightening torque item n m 36 52 15 25 kg m 3.6 5.2 1.5 2.5 a b support the machine by center stand and jack or block. Removal and disassembly pull out the cotter pin and remove the axle nut . Draw out the axle shaft and take off the wheel. Note: do not operate the front brak...

  • Page 98

    Chassis 5-2 unlock the washers and remove the four bolts. Separate the disc plate from the wheel. Caution: do not reuse the lock washers. Using the appropriate drift, drive out the wheel bearings. Inspection wheel bearing inspect the play of wheel bearings inner race by hand while fixing it in the w...

  • Page 99

    5-3 chassis reassemble and remount the front wheel and front brake in the reverse order of disassembly and removal, and also carry out the following steps: reassembly apply grease to the bearings before installing. Wheel bearing suzuki super grease "a" 99000-25010 install the wheel bearings by using...

  • Page 100

    Chassis 5-4 front fork tightening torque item n m 15 30 20 26 kg m 1.5 3.0 2.0 2.6 a b remove the front wheel (see page 5-1). Remove the two bolts and dismount the front caliper. Removal and disassembly.

  • Page 101

    5-5 chassis remove the four bolts and take off the front fender. Remove the two screws and take off the head- light. Remove the two bolts and take off the head- light housing. Disconnect the couplers and lead wires. Remove the lead wires from the headlight housing..

  • Page 102

    Chassis 5-6 r e m o v e t h e t a c h o m e t e r c a b l e a n d t h e speedometer cable. Disconnect the couples of handle switch gear position switch (refer to page 3-4) and . Disconnect the clutch inner cable from the clutch lever. Take off the throttle cable by removing the right handle switch a...

  • Page 103

    5-7 chassis loosen the front fork upper clamp bolts. Remove the stem head bolt. Remove the head of steering stem. Note: slightly loosen the front fork cap bolts to facilitate later disassembly. Loosen the front fork lower clamp bolts. Note: slightly loosen the front fork cap bolts to facilitate late...

  • Page 104

    Remove the cap bolt and draw out the fork spring. Chassis 5-8 invert the fork and stroke it several times to remove the oil. Hold the fork inverted for a few minutes. Remove damper rod bolt by using the special tools and 8mm hexagon wrench. "t" handle 09940-34520 attachment "d" 09940-34561 remove th...

  • Page 105

    Remove the stopper ring. 5-9 chassis remove the oil seal by using the special tool. Oil seal remover 09913-50121 caution the oil seal removed should be replaced with a new one. Inspection damper rod ring inspect the damper rod ring for wear and damage. Inner tube and outer tube inspect the inner tub...

  • Page 106

    Chassis 5-10 reassembly apply suzuki bond no.4 and thread lock cement to the damper rod bolt and tighten the bolt by using the 8 mm hexagon wrench and special tools. Reassemble and remount the front fork in the reverse order of disassembly and removal, and also carry out the following steps: damper ...

  • Page 107

    Fork oil for the fork oil, be sure to use a front fork oil whose viscosity rating meets specifications below. Fork oil type fork oil #10 capacity ( each leg ) hold the front fork vertical and adjust thefork oil level with the special tool. Note: when adjusting oil level, remove the fork spring and c...

  • Page 108

    Remounting when installing the front fork assembly, align the top of inner tube to the upper surface of the steering stem head. Tighten the upper and lower clamp bolt to the specified torque. Tightening torque tightening torque tighten the stem head bolt to the specified torque..

  • Page 109

    Tightening torque item removal and disassembly remove the front wheel ( see page 5-1). Remove the front fork (see page 5-4 ). Remove the steering stem nut and draw out steering stem. Note: hold the steering stem by hand to prevent from falling..

  • Page 110

    Remove the upper and lower steel balls. Number of balls upper lower 22pcs 18pcs remove the outer race fitted on the steering stem. This be done with a chisel. Draw out the two inner races fitted to the top and bottom ends of the head pipe..

  • Page 111

    Inspection inspect and check the remove parts for the following abnormalities. Handlebars distortion. Handlebars clamp wear. Race wear and brinelling. Worn or damaged steel balls. Distortion of steering stem. Reassembly reassemble and remount the steering stem in the reverse order of disa sse mbly a...

  • Page 112

    Suzuki super grease a 99000-25010 tighten the steering stem nut to 40-50n m by using the special tool 09940-14911 steel ball apply grease to the upper and lower inner races when installing the steel balls. Number of balls upper lower 22pcs 18pcs steering stem nut steering nut socket wrench turn the ...

  • Page 113

    A 20-30 n m (2.0-3.0 kg m) tighten the steering stem head bolt, the upper and lower clamp bolts to the special torque (refer to page 6-12). Tightening turque tightening turque caution: after performing the adjustment and instal- ling the steering stem upper head, rock the front wheel assembly forwar...

  • Page 114

    N m 5 8 7 9 25 kg m 0.5 0.8 0.7 0.9 2.5 .0 a b c chassis 5-18 tightening turque item front brake.

  • Page 115

    Remove the bracket. Pull out the pins. Remove the brake pads and replace them. Caution: replace the brake pad with a set, otherwise braking performance will be adversely affected. Reassemble the brake pads and the caliper in the reverse orders. Tighten the caliper mounting bolts to the specified tor...

  • Page 116

    Chassis 5-20 caution: never re-use the brake fluid left over from the last servcing and stored for long periods. Caliper removal and disassembly disconnect the brake hose from the caliper by remove the bolt and catch the brake fluid in a suitable receptacle (refer to page 2-13). Loosen the two pins ...

  • Page 117

    Inspect the cylinder bore wall for nick, scratch or other damage. 5-21 chassis inspection caliper cylinder piston inspect the piston surface for any scratches or damage. Rubber parts inspect the each rubber part for damage and wear. Brake disc measure the disc thickness by using the micrometer. Micr...

  • Page 118

    99000-25100 09900-20701 09900-20606 union bolt dial gauge (1/100mm) caliper mounting bolt 0.3mm with the disc mounted on the wheel check the disc for face runout with a dial gauge, as shown. Magnetic stand service limit reassembly reassemble and remount the caliper in the reverse orders of disassemb...

  • Page 119

    5-23 chassis place a cloth underneath the union bolt on the master cylinder to catch spilled drops of brake fluid. Unscrew the union bolt and disconnect the brake hose from the master cylinder joint. Remove two fitting screws, and remove the cap and diaphragm. Drain brake fluid. Master cylinder remo...

  • Page 120

    Chassis 5-24 inspect the master cylinder bore for any scraches or other damage. Inspection inspect the piston surface for scratches or other damage. Inspect the primary cup, secondary cup and dust seal boot for wear or damage. Caution: wash the master cylinder components with fresh brake fluid befor...

  • Page 121

    5-25 chassis rear wheel and rear brake tightening torque item n m 50 80 5 8 18 28 kg m 5.0 8.0 0.5 0.8 1.8 2.8 a b c support the machine by the center stand. Remove the rear brake adjuster nut and disconnect the brake rod. Pull off the cotter pin and remove the torque link nut and bolt. Removal.

  • Page 122

    Chassis 5-26 pull off the cotter pin and remove the rear axle nut. Loosen the chain adjuster lock nut and adjuster bolt, right and left. Draw out the axle shaft and take off the chain from rear sprocket. Take off the rear wheel and separate the brake panel from the wheel. Flatten the washers and rem...

  • Page 123

    5-27 chassis remove the bearing and retainer from the mounting drum. Remove the cushion from the wheel. Note: removing the left side bearing first makes the job easier. Remove the right and left side wheel bearings..

  • Page 124

    Chassis 5-28 take off the brake shoes. Rear brake remove the cam lever nut and bolt. Pull off the brake cam, washer, o-ring and cam lever..

  • Page 125

    5-29 chassis inspection wheel bearing inspection the wheel bearings for play by hand. Rotate the inner race by hand to inspect whether abnormal noise occurs and it rotates smoothly. Replace the bearing if there are any defects. Service limit 0.25 mm axle shaft using the special tools, check the axle...

  • Page 126

    Chassis 5-30 sprocket inspect the sprocket teeth for wear. If they are worn as illustrated, replace the sprocket and drive chain. Rear brake drum measure the brake drum i.D. To determine the extent of wear and, if the limit is exceeded by the wear noted, replace the drum. The value of this limit is ...

  • Page 127

    5-31 chassis wheel bearing suzuki super grease "a" 99000-25010 reassembly reassemble and remount the rear wheel and rear brake in the reverse order of disassembly and removal, and also carry out the following steps: apply grease to the bearings before installing. Install the wheel bearings by using ...

  • Page 128

    Chassis 5-32 after tightening the four nuts to specification, bend the lock washers. Sprocket tightening torque 18 28 n m (1.8 2.8 kg m) - - apply grease to the brake cam. Brake cam suzuki super grease "a" 99000-25010 warning: be careful not to apply too much grease to the brake cam. If grease gets ...

  • Page 129: Rear Swing Arm

    5-33 chassis rear swing arm tightening torque item n m 50 80 10 15 - - kg m 5 8 - .0 .0 1.0 1.5 - a b remove the rear wheel (see page 5-25). Remove the rear shock absorber units and take off the shock absorber units. Removal and disassembly a b b.

  • Page 130

    Chassis 5-34 remove the two screws and take off the chain case. Remove the swing arm pivot nut and draw out the shaft. Remove the swing arm. Pull off the cotter pin and remove the nut and bolt. Remove the torque link. Remove the chain buffer remove the dust seal covers and draw out the spacers..

  • Page 131

    5-35 chassis bearing puller 09923-73210 draw out the bushings by using the special tools. Rotor remover slide shaft 09930-30102 inspection bushing inspect the bushing for wear and damage. Swing arm pivot shaft using a dial gauge, check the pivot shaft for runout and replace it if the runout exceeds ...

  • Page 132

    Chassis 5-36 reassembly reassemble and remount the swing arm in the reverse order of disassembly and removal, and also carry out the following steps: swing arm bushings force-fit the bushings into the swing arm by using the special tool. Bearing installer set 09924-84510 spacer and dust seal cover a...

  • Page 133: Electrical System

    Electrical system contents 6-1 6-5 6-9 6-12 6-13 6-13 6-16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....

  • Page 134: Ignition System

    6-1 electrical system ignition system description in the full-transistorized ignition system, the electrical energy on the pick-up coil generated by the magneto rotor tip flows to the transistor/ignition timing control circuit. This energy is released in a single surge at the specified ignition timi...

  • Page 135

    Electrical system 6-2 using the pocket tester(rx1 range), measure the resistance between the lead wires in the following table . Inspection pick-up pocket tester 09900-25002 charging coil resistance l _ g approx.120 _ 200 pick-up coil resistance y _ y approx.0.5 _ 2.0 note: when mounting the stator ...

  • Page 136

    6-3 electrical system check the ignition coil with electro tester. Test the ignition coil for sparking performance. Test connection is as indicated. Make sure that the three-needle sparking distance is at least 8 mm. Ignition coil electro tester 09900-28106 std spark performance 8 mm check the ignit...

  • Page 137

    Remove the spark plug from the cylinder. Install the plug cap and place the spark plug on the cylinder head. Remove the seat and disconnect the lead wire from the pick-up coil. Turn the ignition switch on. The ignitor unit is in good condition if the follow- ing is observed. Connect probe of suzuki ...

  • Page 138

    Charging system description the circuit of the charging system is indicated in figure ,which is composed of an ac generator, regulator/rectifier unit and battery. The ac current generated from ac generator is converted by rectifier and is turned into dc current, then it charges the battery. Function...

  • Page 139

    When the engine r/min becomes higher, the generated voltage of ac generator also becomes higher and the voltage between points and of regulator becomes high according, and when it reaches the adjusted voltage of control unit, control unit becomes "on" condition consequently. On the "on" condition of...

  • Page 140

    Inspection charging output check start the engine and keep it running at 5 000r/min. Using the pocket tester, measure the dc voltage between the battery terminal and . If the tester reads under 13.5v or over 16.0v, check the ac generator no-load performance and regulator/rectifier. Note: when making...

  • Page 141

    Regulator/rectifier using the pocket tester (x1 tange), measure the resistance between the lead wires in the following table. If the resistance checked is incorrect, replace the regulator/rectifier. Pocket tester 09900-25002 unit: probe of tester probe of tester r r b b b b b b b/w b/w 7-8 7 8 - 7 8...

  • Page 142: Starter System

    Starter system description the starter system is shown in the diagram below: namely, the starter motor, relay, engine kill switch, ig switch, starter button and battery. Depressing the starter button (on the right handlebar switch box) energizes the relay, causing the contact points to close which c...

  • Page 143

    Carbon brushes when the brushes are worn, the motor will be unable to produce sufficient torque, and the engine will be difficult to turn over. To prevent this, periodically, inspect the length of the brushes, replacing them when they are too short or chipping. Starter motor inspection commutator if...

  • Page 144

    6-11 electrical system brush holder and housing end when fixing brush holder to starter motor case, align the protrusion of the starter motor case with the notch of the brush holder. When installing housing end, fix the protrusion of the starter motor case to the notch on the housing end. Ù starter ...

  • Page 145: Combination Meter

    Electrical system 6-12 remove the combination meter (see page 5-5) disassemble the combination meter. . Combination meter using the pocket tester, check the continuity be- tween lead wires in following diagram. If the continuity measured is incorrect, replace the respective part. Inspection pocket t...

  • Page 146: Lights

    6-13 electrical system lights headlight turn signal light tail/brake light inspect each switch for continuity with the pocket tester referring to the chart. If it is found any abnormality, replace the respective switch as- sembly with new one. Switches pocket tester 09900-25002 ignition switch r o o...

  • Page 147

    Electrical system 6-14 lighting switch Ù engine kill switch starter switch front brake light switch gr o y/w o o/w o/w y/g off o w/b off on 3 1 2 dimmer switch Ù turn signal light switch horn switch g b/w off y/w w y b lg sb 3 1 2 4.

  • Page 148

    6-15 electrical system rear brake light switch o w/b off on gear position indicator light switch wire color neutral low 2nd 3rd 4th top br/r y/l g/l r/b w/y l ground black brown green gray blue light green orange red pink light blue white yellow ........... .......... ........... ......... ............

  • Page 149: Battery

    Electrical system 6-16 battery specifications in fitting the battery to the motorcycle, connect the breather tube to the battery vent. Filling electrolyte remove short sealed tube before filling electrolyte. Fill battery with electrolyte (dilute sulfuric acid solution with acid concentration of 35.0...

  • Page 150

    6-17 electrical system electrolyte specific gravity 1.28 at 20 c (68 f) o o check the electrolyte level and add distilled water, as necessary, to raise the electrolyte to each cell's upper level. Check the battery for proper charge by taking an electrolyte s.G. Reading. If the reading is 1.22 or les...

  • Page 151

    Electrical system 6-18 service life lead oxide is applied to the pole plates of the battery which will come off gradually during the service. When the bottom of the battery case becomes full of the sediment, the battery cannot be used any more. If the battery is not charged for a long time, lead sul...

  • Page 152: Servicing Information

    Servicing information contents 7-1 7-7 7-12 7-14 7-22 7-23 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....

  • Page 153: Troubleshooting

    7-1 servicing information troubleshooting engine complaint engine will not start or is hard to start. Engine stalls easily. Noisy enigne. Symptom and possible causes remedy compression too low plug not sparking no fuel reaching the carburetor 1. Valve clearance out of adjustment 2. Worn valve guides...

  • Page 154

    Servicing information 7-2 complaint symptom and possible causes remedy replace. Replace. Replace. Replace. 1.Clutch control out of adjustment or too much play. 2.Some clutch springs weakened while others are not. 3.Distorted pressure plate or clutch plates. Noisy engine. Slipping clutch. Dragging cl...

  • Page 155

    7-3 servicing information complaint engine lacks power. Engine overheats. Symptom and possible causes remedy 1. Loss of valve clearance. 2. Weakened valve springs. 3. Valve timing out of adjustment. 4. Worn piston ring or cylinder. 5. Poor seating of valves. 6. Fouled spark plug. 7. Worn rocker arms...

  • Page 156

    Battery servicing information 7-4 complaint spark plug become fouled too soon. Spark plug electordes overheat or burn. Generator does not charge. Generator charges,but charging rate is below the specification. Unstable charging. Starter button is not effective. Symptom and possible causes remedy 1.W...

  • Page 157

    7-5 servicing information chassis complaint battery runs down quickly reversed battery polarity. Battery "sulfation" battery discharges too rapidly symptom and possible causes remedy 1. The charging method is not correct. 2. Cell plates have lost much of their active result of over-charging. 3. A sh...

  • Page 158

    Servicing information 7-6 complaint wobbly rear wheel. Rear suspension too soft. Rear suspension too stiff. Noisy rear suspension. Symptom and possible causes remedy 1. Distorted wheel rim. 2. Worn-down rear wheel bearings. 3. Defective or incorrect tire. 4. Loose nut on axle. 5. Worn swing arm bush...

  • Page 159

    1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 special tools 7-7 servicing information item part no. Part name 09900-06107 09900-06108 09900-09003 09900-20101 09900-20202 09900-20203 09900-20205 09900-20508 09900-20606 09900-20701 09...

  • Page 160

    Item part no. Part name servicing information 7-8 09930-44511 09940-14911 09940-34520 09940-34561 09940-50112 09940-53311 09941-34513 09943-74111 rotor holder steering stem nut socket wrench "t"handle attachment "d" fork oil seal installer bearing installer steering race installer fork oil level gau...

  • Page 161

    7-9 servicing information 10 13 11 14 12 15 16 21 18 22 19 17 23 20 24.

  • Page 162

    Servicing information 7-10 27 25 28 26 29 30 37 33 31 38 34 35 32 39 36.

  • Page 163

    7-11 servicing information 40 43 41 44 45 46 49 47 48 42.

  • Page 164: Tightening Torque

    Servicing information 7-12 tightening torque engine item kg m ¤ n m ¤ cylinder head cover bolt camshaft sprocket bolt cylinder head nut 8 mm diam cylinder head nut 6 mm diam cylinder base nut magneto rotor nut primary drive gear/oil pump drive gear nut clutch sleeve hub nut engine oil drain plug eng...

  • Page 165

    7-13 servicing information chassis item kg m ¤ n m ¤ 3.6 5.2 2.0 2.6 2.5 3.5 2.0 3.0 3.5 5.5 1.2 2.0 0.5 0.8 2.5 4.0 2.5 3.5 0.7 0.9 1.5 2.5 5.0 8.0 3.6 5.2 1.0 1.5 2.0 3.0 5.0 8.0 1.8 2.8 0.5 0.8 1.5 3.0 - - - - - - - - - - - - - - - - - - - 36 52 20 26 25 35 20 30 35 55 12 20 5 8 25 40 25 35 7 9 1...

  • Page 166

    Servicing information 7-14 service data valve + guide item standard limit valve diam valve clearance (when cold) valve guide i.D. Valve stem o.D. Valve stem runout valve head thickness valve stem end length valve seat width valve head radial runout valve spring free length (in.& ex.) valve spring te...

  • Page 167

    7-15 servicing information cylinder + piston unit: mm item standard limit compression pressure piston to cylinder clearance cylinder bore piston diam cylinder distortion 1 000 1 400 kpa (10.0 14.0 kg/cm ) 0.045 0.022 57.000 57.015 56.950 56.965 measure at 10 mm from the skirt end - - - - - 2 800 kpa...

  • Page 168

    Servicing information 7-16 conrod + crankshaft unit: mm item standard limit conrod small end i.D. Conrod deflection conrod big end side clearance conrod big end width crankshaft web to web width crankshaft runout 14.004 14.012 0.10 0.45 15.95 16.00 53.0 0.1 - - - 14.040 3.0 1.00 0.05 oil pump item s...

  • Page 169

    7-17 servicing information transmission + drive chain unit: mm item standard limit primary reduction ratio final reduction ratio gear ratios shift fork to groove clearance shift fork groove width shift fork thickness countershaft length (low to 2nd) drive chain drive chain sag 3.470(59/17) 3.214(45/...

  • Page 170

    Servicing information 7-18 carburetor unit: mm item specification mikuni bs26ss 26 26-183 1450 50 r/min 29 0.5 110 0.6 4dh41-2nd p-0 (390) 12.5 37.5 pre-set (2,5/8 turn out) 1.25 0.5-1.0 carburetor type bore size i.D.No. Idle r/min. Flat height main jet (m.J.) main air jet (m.A.J.) jet needle (j,n,)...

  • Page 171

    7-19 servicing information electrical unit: mm item specification note ignition timing spark plug ngk:cr8e n.D.:u24esr-n 10a, 15a type gap 0.7 0.8 - spark performance over 8 at 1 atm. Ignition coil resistance primary w o/w 3.5 5 - -4. Approx. Secondary plug cap o/w approx.16 30 k - - charging y y 0....

  • Page 172

    Servicing information 7-20 brake + wheel unit: mm item standard limit rear brake pedal free travel rear brake pedal height brake disc thickness brake disc runout brake cylinder bore master cylinder piston diam. Brake caliper cylinder bore brake caliper piston diam. Brake drum i.D. Brake lining thick...

  • Page 173

    Front rear item standard limit front fork stroke front fork spring free length front fork oil level rear wheel travel swing arm pivot shaft runout 110 142 75 485 0.6 7-21 servicing information fuel+oil item specification note fuel type fuel tank including reserve reserve engine oil type and grade en...

  • Page 174

    Servicing information 7-22 fuse 10a clamp tail/brake light rear turn signal light (r), (l) starter relay tail/brake light magneto wiring harness gear position indicator clamp magneto wiring harness gear position indicator starter motor lead wire clamp handle switch wire (r&l) horn wire clutch cable ...

  • Page 175

    7-23 servicing information wiring diagram wire c olor black brown green gray blue light green ........... .......... .. ......... ......... ........... ......... B br g gr l lg sp t a f. C . N fuel m bl 12v y y b o lg b/w gr /b w/y r/b g/l y/l br/r y b o lg b/w br /b y/w o gr o/w o y/g y/b b/w o/w w...

  • Page 176: En125Hu

    En125hu supplementary service manual.

  • Page 177

    Prepared by october 2004 part no.:99501-38140-01e printed in china jiangmen dachangjiang group co., ltd..

  • Page 178: Foreword

    Foreword suzuki en125hu is designed to offer superior performance through lightness in weight and four-stroke power. The new en125hu represents another major advance made by suzuki in four stroke motorcycles. This service manual is prepared primarily for experienced mechanics whose job is inspecting...

  • Page 179: En125Hu

    En125hu modifica tions made on the basis of en125-2a rear goods rack engine outer appearance front brake oil tank (canceled ) fuel filter (canceled ) front wheel rear wheel kick starter (added ) carburetor front brake system.

  • Page 180: Carburetor

    Group index 1 2 3 4 5 front wheel and front brake rear wheel and rear brake carburetor kick starter wiring diagram.

  • Page 182: Contents

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

  • Page 183

    1-1 front wheel and front brake front wheel and front brake front wheel assembly detail drawing dismantling of parts front wheel loosen and dismantle front wheel axle nut. Pull out front wheel axle. Support motorcycle with center stand or a jack. Remove speedometer cable and front brake cable. Tight...

  • Page 184

    1-2 remove dust boot and oil seal. Pull out right and left bearings of front wheel. Remove the brake shoes. Dismantle brake cam lever bolt. Tightening torque 5 8n.M 0.5 0.8kg.M front wheel and front brake front brake.

  • Page 185

    Oil seal dismantling tool 09913-50121 1-3 remove the brake cam lever. Remove the oil seal with special tool. Remove the spring collar with special tool. Remove the speedometer drive gear unit. Spring collar clipper 09900-06107 front wheel and front brake.

  • Page 186

    1-4 remove the screw and speedometer drive gear. Play inspection wheel bearing fix wheel hub and inspect with hand the play of bearing inner collar. Rotate the inner collar with hand to see if there is any abnormal noise and if rotation is easy. Replace bearing in case of abnormality. Play front whe...

  • Page 187

    1-5 front wheel axle check with a dial indicator to see if there is any run-out in front axle. In case of excessive run-out, front axle should be replaced. Dial gauge (1/100) 09900-20606 magnetic dial gauge rack v-block (100mm) 09900-20701 09900-21304 service limit 0.25mm wheel rim note: the run-out...

  • Page 188

    1-6 brake shoe brake panel incorporate a brake lining wear limit indicator. If the lining condition is normal, the brake camshaft index mark line , when extended, will fall within the range embossed on the brake panel (when brake is on). First check that the brake system is properly adjusted. Then c...

  • Page 189

    Install the wheel bearings by using the special tool. 1-7 reassembly reassemble and remount the front wheel in the reverse order of disassembly and removal, and also carry out the following steps: wheel bearing bearing fitting tools 09924-84510 apply lubricating grease to bearing. Suzuki super lubri...

  • Page 190: Contents

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

  • Page 191

    2-1 rear wheel and rear wheel brake rear wheel assembly detail drawing dismantling of parts rear wheel support motorcycle with center stand; screw out rear brake adjusting nut and dismantle rear brake lever; pull out split pin and dismantle torsion bar tightening nut; loosen the nut and bolt on the ...

  • Page 192

    2-2 remove the rear wheel axle nut and remove rear wheel axle; remove the chain from the large sprocket; remove the rear wheel; flatten the lock washer and screw out the sprocket nuts; remove the sprocket hub and sprocket; separate the rear wheel and drive sprocket; rear wheel and rear brake rear sp...

  • Page 193

    Rear brake 2-3 remove the brake shoes. Remove the brake cam lever. Remove the brake camshaft, gasket, o-ring and camshaft swing arm; inspections wheel bearing rear wheel axle wheel rim spoke nipple tire brake shoe brake drum (see pages 1-4) (see pages 1-5) (see pages 1-5) (see pages 1-5) (see pages ...

  • Page 194

    2-4 rear sprocket excessively worn sprocket cause chain noise and accelerate sprocket wear. Inspect wear of sprocket teeth. In case of excessive wear as shown in the figure, replace sprocket and chain as a set; rear sprocket dumper lubber check if there are wear and crack in the dumper lubber. In ca...

  • Page 195

    2-5 tighten the following bolts and nuts at specified torques. N m kg m 10-15 18-28 5-8 50-80 torsion bar tightening nut sprocket nut brake cam lever nut rear wheel axle nut tightening 1.0-1.5 1.8-2.8 0.5-0.8 5-8 rear wheel and rear brake item.

  • Page 196: Contents

    Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....

  • Page 197

    3-1 carburetor carburetor structure jet needle piston valve pilot air screw throttle valve stop screw needle valve float pilot jet needle jet main jet carburetor throttle valve reticule mark idle speed (r/min) float level main jet (m.J) main air jet (m.A.J) jet needle (j.N.) item mikuni 20.4 vm22-40...

  • Page 198

    3-2 dismantling and separation of parts dismantling carburetor turn fuel switch to "off" position; remove the fuel hose; unscrew bolt and drain gasoline in carburetor; warning: handle gasoline with care as it is inflammable and explosive. Note: there is no fuel filter on carburetor oil inlet tube in...

  • Page 199

    3-3 pull out float pin and remove the float chamber; remove the needle valve; dismantle bolt , remove float needle valve seat pressure plate and take out float needle valve ; dismantle main jet , needle jet and remove holder ; dismantle pilot jet ; dismantle pilot screw , remove spring , gasket and ...

  • Page 200

    3-4 remove the throttle cable clamp from throttle valve; remove the needle jet; dismantle top cap unit; remove the starter unit; carburetor.

  • Page 201

    3-5 inspection and fitting float valve in case there is foreign matter between valve seat and needle, there is overflow of oil when oil supply continues. In case wear of valve seat and needle exceeds the limit, the same trouble occurs. On the contrary, when the needle is jammed, gasoline shall not e...

  • Page 202

    3-6 fit needle valve in throttle valve as shown in the figure; refitting fit other parts of carburetor in the reverse order of removal. Carburetor.

  • Page 204: Kick Starter

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

  • Page 205

    4-1 kick starter dismantling kick starter remove the bolt and remove the kick starter ; remove the clutch cover ; remove the kick starting gear washer and kick starting gear ; dismantle bolts , remove kick starting guide plate and limiting plate ; remove kick starting ratchet wheel , spring and wash...

  • Page 206

    4-2 remove the clutch unit (refer to "en125-2a service manual" 99500h06100-01e); remove the kick starting idle wheel clip , washer and remove kick starting idle wheel and washer ; take out kick starting idle wheel shaft after separating right and left crankcases; dismantling cylinder head and cylind...

  • Page 207

    4-3 inspection inspect wear of parts. Replace parts with obvious wear. Refitting fit kick starting device in reverse order of removal. When fitting kick starting ratchet, align it with the mark. Fit kick starting bush spring, bush and clip in the right crankcase and then fit ratchet. When fitting ra...

  • Page 208: Wiring Diagram

    Handle-sw ,r rear-turn, r rear-comb, lamp rear-turn, l fuse-box ba tter y engine ear th frame ear th st ar ter-rela y st ar ter-mot or magnet o neutral-sw horn turnsignal horn dimmer handle-sw ,l alarm ignition-sw front -turn, r head-lam position-lam front -turn, l speedometer lights engine st op st...