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Vento Phantom R4i Service Maintenance Manual

Summary of Phantom R4i

  • Page 1

    Vento motorcycles rev no.01/ page 1of 84 vento motorcycles motorcycle division doc.Title :service manual phantom r4i doc.No(model code):vs-01-a-4-a brand name :vento revision number : 01 date of release :26.01.2004 page :1 of 84 page description page description 4 general information 33 left crankca...

  • Page 2

    Vento motorcycles rev no.01/ page 2of 84 phantom r4i service & maintenance manual.

  • Page 3

    Vento motorcycles rev no.01/ page 3of 84 forward this service manual contains an introductory description on vento phantom r4i, and procedures for its inspection/service and overhaul of its main components. Other information’s considered as generally known is not included. Read general information s...

  • Page 4

    Vento motorcycles rev no.01/ page 4of 84 chapter 1 general information model identification……………………………………………… fuel and engine oil………………………………………………… break-in procedures……………………………………………… precautions and general instructions…………………… specifications ……………………………………………………… illegal copying it is the polic...

  • Page 5

    Vento motorcycles rev no.01/ page 5of 84 model identification type & identification frame number frame number is engraving on the steel tube of frame as shown in figure. Engine number engine number is engraving on side of the crankcase as shown in figure. Both frame nuber and engine number are desig...

  • Page 6

    Vento motorcycles rev no.01/ page 6of 84 break-in procedures during manufacture only the best possible materials are used and all machined parts are finished to a very high standard but it is still necessary to allow the moving parts to ‘‘brek-in’’ before subjecting the engine to maximum stresses. T...

  • Page 7

    Vento motorcycles rev no.01/ page 7of 84 precautions and general instructions general precautions: warning o proper service and repair procedures are important for the safety of the service mechanic and the reliability of the vehicle. O when two or more persons are working together, pay attention to...

  • Page 8

    Vento motorcycles rev no.01/ page 8of 84 s p e c i f i c at i o n s description parameter overall length 1950mm overall width 675mm overall height 1130mm wheelbase 1375mm minimum ground clearance 115mm vehicle dry weight 115kg engine type cylinder borexstroke displacement compression ratio valve eng...

  • Page 9

    Vento motorcycles rev no.01/ page 9of 84 item parameter specification magneto ignition system ignition timing ‘f’ mark ‘ii full advance magneto output spark plug spark plug gap fuse horn battery cdi 13º btdc @1400rpm 28º btdc@ 4000 rpm 114w@4000rpm c7hsa 0.6~0.7mm 8a 100db 12v - 6ah/yuasa/ytx7a-bs l...

  • Page 10

    Vento motorcycles rev no.01/ page 10of 84 item parameter specification driving system clutch system transmission system primary gear reduction gear ratio first second max speed dry shoe automatic cvt 10.86~2.64 2.8(42/15) 3.077(40/13) 85±5km/h carburetor model code piston dia main jet slow running j...

  • Page 11

    Vento motorcycles rev no.01/ page 11of 84 suspension front shock absorber rear shock absorber front wheel specification rear wheel specification tire pressure front tire pressure rear front brake rear brake fuel tank capacity engine oil capacity liquid pressure type (compressibility 130 mm) liquid p...

  • Page 12

    Vento motorcycles rev no.01/ page 12of 84 chapter 2 periodic maintenance and service • periodic maintenance and service schedule • storage battery • spark plug • air cleaner • special tools • specified torque values.

  • Page 13

    Vento motorcycles rev no.01/ page 13of 84 periodic maintenance and service 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. Mileages are expressed in terms of kilometer, mil...

  • Page 14

    Vento motorcycles rev no.01/ page 14of 84 storage battery battery inspection and checking procedure ► open the cover as shown in picture, and then remove the battery from the battery box. ► disconnect negative terminal / cable first then positive terminal / cable of battery . ►measure the voltage be...

  • Page 15

    Vento motorcycles rev no.01/ page 15of 84 spark plug neglecting the spark plug maintenance eventually leads to difficult starting and poor performance. If the spark plug is used for a long time, the electrode gradually burns away and carbon builds up along the inside part. In accordance with the per...

  • Page 16

    Vento motorcycles rev no.01/ page 16of 84 air cleaner clean every 3000 kms 1890 miles replace every 12000 kms (1750 miles) if the air cleaner is clogged with dust, air intake resistance will be increased with a result decrease in power output and will be increase in fuel consumption. Check and clean...

  • Page 17

    Vento motorcycles rev no.01/ page 17of 84 special tools list necessary tools to disassemble and install motorcycle engine as follows code tools code purpose 1 2 3 4 5 6 7 8 9 10 t01 t02 t03 t04 t05 t06 t07 t08 t09 t10 “t”shape tappet adjusting tool guide cylinder tools 8,10,12,13 tool for fly wheel ...

  • Page 18

    Vento motorcycles rev no.01/ page 18of 84 ○ 1 ○ 2 ○ 3 ○ 4.

  • Page 19

    Vento motorcycles rev no.01/ page 19of 84 ○ 7 ○ 8 ○ 9 ○ 10 s p e c i f i e d t o r q u e va l u e s it is important for the components / fasteners to be tighteed as per specified torque no. Na me qty torque.

  • Page 20

    Vento motorcycles rev no.01/ page 20of 84 chapter 3 e n g i n e detail information of important parts 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 tapping screw for fan cover assy. Screw for fan cover assy. Tapping screw for top and b...

  • Page 21

    Vento motorcycles rev no.01/ page 21of 84 o rings — 7 nos. Oil seals — 4 nos. Bearing—13nos s.No. Size (mm) qty. Description location 1 9Фx1.6 2 inlet and exhaust valve guide engine 2 13.7Фx1.5 1 chain guide engine 3 9.5Фx1.5 1 chain adjustor engine 4 18Фx3.5 1 oil level gauge engine 5 30.5Фx3 1 fil...

  • Page 22

    Vento motorcycles rev no.01/ page 22of 84 pin shaft—2nos 2 6202 1 middle shaft—gearbox cover engine 3 6204 1 output shaft—gearbox cover engine 4 6004 1 output shaft—left crank case engine 5 6002 1 middle shaft—left crank case engine 6 6301 1 output shaft—left crank case engine 7 tm-scd4asscs12 1 lef...

  • Page 23

    Vento motorcycles rev no.01/ page 23of 84 gasket— 7 nos. Gear ratio s.No. Size (mm) qty. Description location 1 5Фx6 1 starter clutch engine 2 4Фx6.5 1 oil pump engine s.No. Gasket type qty. Location 1 cylinder head cover anti-oil asbestos rubber 1 engine 2 cylinder head steel 1 engine 3 cylinder bo...

  • Page 24

    Vento motorcycles rev no.01/ page 24of 84 sprocket information unidirectional fitment of engine parts read the following instruction carefully and assure spare parts installed in right position, otherwise it may damage engine seriously. Gear ratio gear no teeth gear no teeth 2.8 a 1 15 a 2 42 3.077 ...

  • Page 25

    Vento motorcycles rev no.01/ page 25of 84 1. All marks of the following parts should be towards combined surface of left crankcase and transmission case ►output shaft of left crankcase, middle shaft, output shaft bearing 6004,6002,6301, and output shaft of transmission case, middle shaft, output sha...

  • Page 26

    Vento motorcycles rev no.01/ page 26of 84 engine disassembly and assembly disassembly assembly guide-fan cover/ fan cover/carburetor left crankcase assy./gearbox assy. Left crankcase cover/gasket gearbox outside part of left crankcase crankshaft/left and right crank case/starter motor chain adjustor...

  • Page 27

    Vento motorcycles rev no.01/ page 27of 84 e n g i n e c o w l a s s e m b ly disassembly • assembly sequence is just reverse of disassembly c y l i n d e r h e a d a s s e m b ly screw (6) bolt (7) fan cover assy. (8) cover (9) cooling pipe (5) screw (10) bolt (1) top cowling bottom cowling top cowl...

  • Page 28

    Vento motorcycles rev no.01/ page 28of 84 engine removal and installation disassembly assembly cylinder head cover cylinder head right against mark “t” on magneto exhaust& inlet valve oil seals assy./gasket (the bottom of exhaust port) inlet & exhaust valve spring/spring holder/lock clip timing chai...

  • Page 29

    Vento motorcycles rev no.01/ page 29of 84 1. Cylinder head cover fixing bolt 10~12n·m 2. Chain tensioner bolt and fixing bolt 10~12 n·m 3. Cam shaft holder nut 22~25 n·m 4. Inlet pipe locknut 10~12 n·m 5. Timing bolt 10~12 n·m cam shaft holder assembly d i s a s s e m b ly a s s e m b ly cam shaft h...

  • Page 30

    Vento motorcycles rev no.01/ page 30of 84 ` piston installation.

  • Page 31

    Vento motorcycles rev no.01/ page 31of 84 removal: the first ring the second ring oil ring oil ring oil ring gasket piston installation: the installation sequence is just reverse of removal. Note: • the first ring is white ring, and the second ring is black one. • the sides of the first ring and the...

  • Page 32

    Vento motorcycles rev no.01/ page 32of 84 l e f t c r a n k c a s e c o v e r i n s ta l l at i o n removal left crankcase cover assy. Brake cable clip (1) main stand stopping holder ventilation pipe clip (3) throttle cable holder (4) left crankcase cover (5) guide board (6) installation: the instal...

  • Page 33

    Vento motorcycles rev no.01/ page 33of 84 r i g h t c r a n k c a s e c o v e r a c c e s s o r i e s removal: installation the installation sequence is just reverse of removal. Notice 1. The clearance between flywheel trigger and pickup is 0.5±0.2mm. 2. Check specified clearance between flywheel tr...

  • Page 34

    Vento motorcycles rev no.01/ page 34of 84 r i g h t c r a n k c a s e a c c e s s o r i e s removal locknut 1 electric start transition gears 5 bolt 7 special tool t05 gasket 2 electric start transition gear shaft 6 oil pump sprocket end cover 8 start clutch complete (3 nut 9 half round plate 4 oil ...

  • Page 35

    Vento motorcycles rev no.01/ page 35of 84 l e f t c r a n k c a s e a c c e s s o r i e s i n s ta l l at i o n removal installation nut 8 washer 7 drive impeller 6 starting gear sector assy. 9 kick starting gear assy. 10 nut 15 cvt nut washer 14 centric disc 13 starter spring plate 11 v –belt (16 d...

  • Page 36

    Vento motorcycles rev no.01/ page 36of 84 crankcase installation removal installation bolt 1 left crankcase assy. 8 right crankcase assy. 2 chain 6 pin 7 gasket 3 crankshaft assy. 4 crankshaft assy. 4 pin 7 /gasket 3 timing chain 6 right crankcase assy. 2 left crankcase assy. 8 bolt 1 oil seal 5 oil...

  • Page 37

    Vento motorcycles rev no.01/ page 37of 84 transmission case installation removal transmission case assy. Left crankcase assy. 1 transmission case cover assy. 2 middle shaft assy. 4 output shaft assy. 5 input shaft bearing input shaft (3) middle shaft bearing output shaft bearing middle shaft bearing...

  • Page 38

    Vento motorcycles rev no.01/ page 38of 84 c l u t c h s h o e / m o v a b l e d r i v e n fa c e removal disassembly driven wheel disc assy. Spring bush (6) clip circle 17 clutch disc 1 fixing axes 13 /sliding pin 12 clutch side board 18 nut 2 seal 7 /driven step less shifting disc 9 spring 19 /clut...

  • Page 39

    Vento motorcycles rev no.01/ page 39of 84 kick shaft assembly removal kick start shaft assy. Bush 6 bush 1 gasket 2 spring 3 pin 5 kick start shaft 4 installation the installation sequence is the reverse of removal. Notice • daub bush 1 with proper lubrication to install it. • daub shaft end with pr...

  • Page 40

    Vento motorcycles rev no.01/ page 40of 84 movable drive face note: • before installing part (8), insert 3 cushion gaskets into (8). • bush 2 should be slide freely. Removal face fixed drive 1 bush 2 plate drive 8 cushion gasket 9 roller 7 washer 3 bush 4 washer 6 face movable drive 5 installation fa...

  • Page 41

    Vento motorcycles rev no.01/ page 41of 84 s u p e r c l u t c h i n s ta l l at i o n removal clutch gear comp. 1 rolling needle bearing 2 screw m6 3 clutch hub 4 pin 5 rolling pole 6 spring bush 7 and spring 8 clutch outside circle rubber 9 spring seat 10 clutch side circle 11 installation the inst...

  • Page 42

    Vento motorcycles rev no.01/ page 42of 84 p o w e r t r a n s m i s s i o n from engine piston (1) connecting rod (2) crank (11) driving disc driven disc (6) clutch (7) gearbox input axes (10) from kick start kicking start shaft kicking start axes (5) start gear transition little gear transition big...

  • Page 43

    Vento motorcycles rev no.01/ page 43of 84 lubrication the engine oil performs the following functions • lubrication prevents friction, metal to metal contact. • cooling prevents overheating. • anti rust prevents corrosion. • cleaning prevents sludge formation, remove carbon particles. • sealing agen...

  • Page 44

    Vento motorcycles rev no.01/ page 44of 84 l u b r i c at i o n d i a g r a m rocker arm camshaft assy. Crank assy, oil pump assy. Filter assy..

  • Page 45

    Vento motorcycles rev no.01/ page 45of 84 v a lv e c l e a r a n c e a d j u s t m e n t p r o c e d u r e engine in cool condition • remove cylinder head cover. • remove fan cover. • keep “t” mark on flywheel to the same line with the mark on right crankcase cover. • ensure timing mark of cam sproc...

  • Page 46

    Vento motorcycles rev no.01/ page 46of 84 testing procedure step -1 1 warming up the engine to normal running temperature (hot condition). 2 remove spark plug and connect compression pressure gauge. 3 ensure that (a) fuel switch/cock is in “off” position. (b) ignition switch is in “off”position. 4 a...

  • Page 47

    Vento motorcycles rev no.01/ page 47of 84 cylinder head/valve cylinder / piston item standard cylinder pressure 12±1kg/cm 2 inlet 0.03~0.05mm valve clearance exhaust 0.05~0.06mm inlet 26.72±0.05 cam shaft cam lobe height exhaust 26.68±0.05 inlet 4.970~4.980 mm stem od exhaust 4.955~4.965 mm inlet 5....

  • Page 48

    Vento motorcycles rev no.01/ page 48of 84 chapter 4 air fuel system carburetor specification fuel consumption curve type model piston dia main jet slow jet mixture screw needle position float height cv pd24j 24mm 191 19 1.5±0.5 turnout 3 rd groove from top 15±1mm.

  • Page 49

    Vento motorcycles rev no.01/ page 49of 84.

  • Page 50

    Vento motorcycles rev no.01/ page 50of 84 air-fuel flow circuit fuel is being supplied to the carburetor from fuel tank by gravity feeding controlled fuel cock assy. Air filter box is fitted on the left side of the motorcycle. Fuel gets atomized and mixes with clean air in right proportion in the ca...

  • Page 51

    Vento motorcycles rev no.01/ page 51of 84 air fuel mixture ratio: carburettor circuits: starting 7~8: 1 the phantom r4i scooter has 6 main circuits idling speed 10~12: 1 1. Fuel intake circuit slow speed 12~14: 1 2. Choke circuit medium speed 15~17: 1 3. Idling speed circuit high speed: 13-15:1 4. S...

  • Page 52

    Vento motorcycles rev no.01/ page 52of 84 carburetor circuits 1. Fuel intake circuit: from fuel tank fuel comes into float chamber of carburetor by gravity feed. Separate vent is provided at lh side of carburetor body to maintain inside atmospheric pressure. When fuel starts filling the float chambe...

  • Page 53

    Vento motorcycles rev no.01/ page 53of 84 3. Idling circuit: after starting operation choke is released, more air starts flowing thru the venturi. From slow jet fuel is sucked due to venturi effect. A separate passage from the air filter side is coming at the diffuser of the slow jet for the atomiza...

  • Page 54

    Vento motorcycles rev no.01/ page 54of 84 6.High speed circuit during acceleration the throttle valve (piston) is fully raised, more air is being supplied due to higher velocity. Hence pressure drops at the opening of throttle jet needle. Where as more fuel is sucked from the main jet due to tappern...

  • Page 55

    Vento motorcycles rev no.01/ page 55of 84 carburetor removal & installation removal: 1. Remove rear seat of motorcycle. 2. Turn fuel switch “off” position. 3. Disconnect fuel pipe from carburetor by pressing clip. 4. Loosen the clamp over air cleaner connecting tube (air duct). 5. Drain the fuel fro...

  • Page 56

    Vento motorcycles rev no.01/ page 56of 84 carburetor tuning or adjustment procedure after installation the carburetor in the engine as per above said procedure, follow the following steps: 1. Warming up the engine to the normal running temperature. 2. Adjust idling speed to 1400 rpm by throttle stop...

  • Page 57

    Vento motorcycles rev no.01/ page 57of 84 chapter 5 chassis installation of vehicle body specified torque value no. Item qty. Torque front wheel/front absorber 1 front wheel axis locknut 1 55-62nm 2 fixing bolt between front absorber and support under connecting board assy. 4 37-44n.M 3 fixing bolt ...

  • Page 58

    Vento motorcycles rev no.01/ page 58of 84 front wheel assembly disassembly locknut 13 front wheel centre bolt 6 front wheel left bush 7 gear seat assy. Front wheel assy. Front wheel, seal ring(8 tire 1 rim assy. Rim 4 front wheel bush 5 bearing 9 valve (3 valve cap 2 speedometer gear (11), gear set ...

  • Page 59

    Vento motorcycles rev no.01/ page 59of 84 rear wheel assembly disassembly rear wheel assy. Tire 1 rear rim assy. Brake shoe assy. 11 brake shoe pulling spring 4 brake tension spring 10 anti-dust cover (7) anti-dust assembling board (8) bolt m6x35 (6) rear braking rocker arm (9) seal ring (13) rear b...

  • Page 60

    Vento motorcycles rev no.01/ page 60of 84 muffler assembly disassembly nut m8 13 flat washerφ8 11 spring washerφ8 12 , bolt m8x125 2 ,bolt m8x40 4 special nut 5 exhaust pipe assy. 1 exhaust pipe bush 6 bolt m8x35 10 , bolt m8x55 9 nut m16x1.5 7 outside orientation bush 8 muffler connecting board 3 i...

  • Page 61

    Vento motorcycles rev no.01/ page 61of 84 front fork assembly disassembly nut m10x125x50 10 front left absorber assy. 9 , front right absorber assy. 8 special locknut 1 anti dust spring assy 2 upper steel bowl 3 upper steel ball 4 under connecting support assy. 7 taper roller bearing (6) upper steel...

  • Page 62

    Vento motorcycles rev no.01/ page 62of 84 front shock absorber disassembly bolt (1) o-seal ring (2) absorber spring (3) piston lever 4 screw (5) and gasket inner tube assy. (6) piston lever/piston ring (7) buffer spring (8) outer tube assy. Anti-dust ring assy. 10 oil seal stopper ring 11 oil seal a...

  • Page 63

    Vento motorcycles rev no.01/ page 63of 84.

  • Page 64

    Vento motorcycles rev no.01/ page 64of 84 hydraulic brake disc system hydraulic brakes operating principle: it is operating on the principle that the liquid is not compressible, so the force and motion can be transmitted through a liquid media. Master cylinder: as the brake lever is pressed, the mas...

  • Page 65

    Vento motorcycles rev no.01/ page 65of 84 1.Oil cap 5.Clip ring 9.Tension spring 2.Oil gasket 6.Bowl 10.Outlet oil hole 3.Inlet oil hole 7.Stopper 11.Supplement hole 4. Stopper anti-dust cover 8. Bowl 12.Master cylinder master cylinder assy. Fig.6.

  • Page 66

    Vento motorcycles rev no.01/ page 66of 84 disc brake caliper assy..

  • Page 67

    Vento motorcycles rev no.01/ page 67of 84 overhauling procedure of disc brake.

  • Page 68

    Vento motorcycles rev no.01/ page 68of 84 general instruction: 1 never handle brake fluid by bare hands for a longer time 2 if brake fluid comes in contact with eyes, wash eyes with cold water and consult a doctor immediately. 3 never allow brake fluid to come in contact with any painted parts as it...

  • Page 69

    Vento motorcycles rev no.01/ page 69of 84 front wheel/ absorber/ control rear wheel description standard driver 32 psi tire air pressure driver and passenger 32 psi free distance of front absorber spring 130mm disc brake system description standard specified disc brake oil dot3 or dot4 the thickness...

  • Page 70

    Vento motorcycles rev no.01/ page 70of 84 chapter 6 electrical magneto assy construction: magneto assembly consists of a stator & rotor assy. Type of stator coils construction: -- star connection. Stator assembly: • six coils of stator: seven coils for light/battery charging & one coil for charging ...

  • Page 71

    Vento motorcycles rev no.01/ page 71of 84 note: all the resistance value are measured with reference to ground wire (black) battery testing procedure remove the battery from the motorcycle/scooter. Connect the battery on load tester ensuring red lead of tester to (+ve) and black lead to (-ve) termin...

  • Page 72

    Vento motorcycles rev no.01/ page 72of 84 note 1 incase charging output is less than 0.6 amp or more than 2.0amp then replace the voltage regulator with new one and recheck. Note 2 ammeter: -----series connection inline with positive battery wire to measure dc –amp. Voltmeter: ---parallel connection...

  • Page 73

    Vento motorcycles rev no.01/ page 73of 84 electronic ignition components test for any ignition problems, always check the components as per the following procedure. 1. Spark plug: check spark plug after cleaning in “spark plug cleaning and testing machine” replace if …… • short • worn out electrode ...

  • Page 74

    Vento motorcycles rev no.01/ page 74of 84 ignition timing test 1. Remove the ignition timing inspection hole cap. 2. Connect the timing light (stroboscope). 3. Start the engine and aim the timing light at ignition mark on the magneto fly wheel (as shown in figure). •during idling speed ignition mark...

  • Page 75

    Vento motorcycles rev no.01/ page 75of 84 head light indicator & meter light head light disassembly remove front cover headlight leg shied remove headlight bulb-12v 18w/18w×2 by unscrewing fixing screw adjust focus through adjusting nut remove and install night small light-12v 3 w×2 head light assem...

  • Page 76

    Vento motorcycles rev no.01/ page 76of 84.

  • Page 77

    Vento motorcycles rev no.01/ page 77of 84 main electrical components specification some important specification-electrical battery charging system item specification capacity 12volt-6ah/ytx7a-bs/yuasa specific gravity at (27 ) fully charged needs charging 1.220~1.240 below 1.220 charging current 0.6...

  • Page 78

    Vento motorcycles rev no.01/ page 78of 84 p r e - d e i v e r y i n s p e c t i o n ( p. D . I . ) it is very important to check every motorcycle/scooter to a thorough p.D.I. Before delivery. Please do the following procedures and send main information to dealer. 1. Wash the vehicle with mild automo...

  • Page 79

    Vento motorcycles rev no.01/ page 79of 84 pdi check points check brake lever free play 10-20 mm check speedometer & odometer& digital clock check proper functioning of all electrical switches check turn signals for proper functioning check tire pressure 2.25kg/cm2 (32psi) check torque of engine moun...

  • Page 80

    Vento motorcycles rev no.01/ page 80of 84 chapter 7 trouble shooting engine complaint symptom and possible causes remedy engine does not start, or is hard to start. Compression too low 1. Excessively worn cylinder or piston & piston rings. 2. Sticky piston rings in groove. 3. Compression leaks from ...

  • Page 81

    Vento motorcycles rev no.01/ page 81of 84 4. Piston rings or ring grooves worn. Noise seems to come from crankshaft 1. Worn or burnt crankshaft bearings. 2. Worn or burnt conrod big-end bearings. 3. Due to wear rattling bearings. 4. Too large thrust clearance. Excessive valve chatter 1. Too large va...

  • Page 82

    Vento motorcycles rev no.01/ page 82of 84 engine runs poorly in high-speed range. 1. Excessively worn cylinder or piston rings. 2. Sticky piston ring in grooves. 3. Spark plug gaps too less. 4. Ignition not advanced sufficiently due to poorly working cdi & ignition coil unit. 5. Defective magneto st...

  • Page 83

    Vento motorcycles rev no.01/ page 83of 84 7. Use of incorrect spark plug. 8. Clogged exhaust pipe/muffler. 9. Clogged air intake with dust oil change & use specified. Clean or replace. Clean carburetor complaint symptom and possible causes remedy trouble with starting. 1. Starter jet is clogged. 2. ...

  • Page 84

    Vento motorcycles rev no.01/ page 84of 84 electrical complaint symptom and possible causes remedy no sparking or poor sparking. 1. Defective cdi & ignition coil unit. 2. Defective spark plug. 3. Defective magneto stator coil. 4. Loose connection of lead wire. 5. Defective pick-up coil replace. Repla...

  • Page 85

    Vento motorcycles rev no.01/ page 85of 84 complaint symptom and possible causes remedy unstable charging. 1. Defective regulator/rectifier. 2. Lead wire insulation frayed due to vibration, resulting in intermittent shorting. 3. Magneto coil internally shorted. Replace. Replace. Replace. Starter butt...

  • Page 86

    Vento motorcycles rev no.01/ page 86of 84 battery discharges too rapidly. “sulfation”acidic white powdery substance or spots on surface of cells battery “sulfation” 1. Dirty container top and sides. 2. Battery is too old. 1.Cracked battery case 2.Battery has left in a run-down condition for a long t...

  • Page 87

    Vento motorcycles rev no.01/ page 87of 84 5. Loose nuts or bolts for engine mounting. 6. Worn rear wheel bearing. Replace. Retighten. Replace. Rear suspension too soft. 1. Weakened shock absorber spring. 2. Oil leaks from rear shock absorber. Replace. Replace. Noisy rear suspension. 1. Loose nuts on...

  • Page 88

    Vento motorcycles rev no.01/ page 88of 84 brake squeaking. 1. Carbon adhesion on pad surface. 2. Tilted pad. 3. Damaged wheel bearing. 4. Worn pad or disc. 5. Foreign material entered into brake fluid. 6. Clogged return port of master cylinder. 7. Brake shoe surface glazed. 8. Loose front-wheel axle...