Piaggio Vespa WORKSHOP LX 4tempi Workshop Manual

WORKSHOP MANUAL

633424

LX 4tempi

WORKSHOP

LX 4tempi

MANUAL

The descriptions and illustrations given in this publication are not binding. While the basic specifications
as described and illustrated in this manual remain unchanged, PIAGGIO-GILERA reserves the right, at

any time and without being required to update this publication beforehand, to make any changes to

components, parts or accessories, which it considers necessary to improve the product or which are

required for manufacturing or construction reasons.

Not all versions shown in this publication are available in all Countries. The availability of single versions

should be checked at the official Piaggio sales network.

"© Copyright 2007 - PIAGGIO & C. S.p.A. Pontedera. All rights reserved. Reproduction of this publication

in whole or in part is prohibited."

PIAGGIO & C. S.p.A. - After-Sales

V.le Rinaldo Piaggio, 23 - 56025 PONTEDERA (Pi)

WORKSHOP MANUAL

LX 4tempi

This workshop manual has been drawn up by Piaggio & C. Spa to be used by the workshops of Piaggio­Gilera dealers. This manual is addressed to Piaggio service mechanics who are supposed to have a
basic knowledge of mechanics principles and of vehicle fixing techniques and procedures. Any important
changes made to the vehicles or to specific fixing operations will be promptly reported by updates to this
manual. Nevertheless, no fixing work can be satisfactory if the necessary equipment and tools are
unavailable. It is therefore advisable to read the sections of this manual relating to specific tools, along
with the specific tool catalogue.

N.B. Provides key information to make the procedure easier to understand and carry out.

CAUTION Refers to specific procedures to carry out for preventing damages to the vehicle.

WARNING Refers to specific procedures to carry out to prevent injuries to the repairer.

Personal safety Failure to completely observe these instructions will result in serious risk of personal

injury.

Safeguarding the environment Sections marked with this symbol indicate the correct use of the vehicle
to prevent damaging the environment.

Vehicle intactness The incomplete or non-observance of these regulations leads to the risk of serious
damage to the vehicle and sometimes even the invalidity of the guarantee.

INDEX OF TOPICS

CHARACTERISTICS CHAR

TOOLING TOOL

MAINTENANCE MAIN

TROUBLESHOOTING TROUBL

ELECTRICAL SYSTEM ELE SYS

ENGINE FROM VEHICLE ENG VE

ENGINE ENG

SUSPENSIONS SUSP

BRAKING SYSTEM BRAK SYS

CHASSIS CHAS

PRE-DELIVERY PRE DE

TIME TIME

INDEX OF TOPICS

CHARACTERISTICS CHAR

Characteristics LX 4tempi

Rules

Safety rules

- If work can only be done on the vehicle with the engine running, make sure that the premises are well­ventilated, using special extractors if necessary; never let the engine run in an enclosed area. Exhaust
fumes are toxic.

- The battery electrolyte contains sulphuric acid. Protect your eyes, clothes and skin. Sulphuric acid is
highly corrosive; in the event of contact with your eyes or skin, rinse thoroughly with abundant water
and seek immediate medical attention.

- The battery produces hydrogen, a gas that can be highly explosive. Do not smoke and avoid sparks
or flames near the battery, especially when charging it.

- Fuel is highly flammable and it can be explosive given some conditions. Do not smoke in the working
area, and avoid open flames or sparks.

- Clean the brake pads in a well-ventilated area, directing the jet of compressed air in such a way that
you do not breathe in the dust produced by the wear of the friction material. Even though the latter
contains no asbestos, inhaling dust is harmful.

Maintenance rules

- Use original PIAGGIO spare parts and lubricants recommended by the Manufacturer. Non-original or
non-conforming spares may damage the vehicle.

- Use only the appropriate tools designed for this vehicle.

- Always use new gaskets, sealing rings and split pins upon refitting.

- After removal, clean the components using non-flammable or low flash-point solvent. Lubricate all the
work surfaces except the tapered couplings before refitting.

- After refitting, make sure that all the components have been installed correctly and work properly.

- For removal, overhaul and refit operations use only tools with metric measures. Metric bolts, nuts and
screws are not interchangeable with coupling members with English measurement. Using unsuitable
coupling members and tools may damage the scooter.

- When carrying out maintenance operations on the vehicle that involve the electrical system, make
sure the electric connections have been made properly, particularly the ground and battery connections.

CHAR - 2

LX 4tempi Characteristics

Vehicle identification

VEHICLE IDENTIFICATION

Specification Desc./Quantity

Chassis prefix ZAPC383000001001

Engine prefix C383M

Dimensions and mass

Specification Desc./Quantity

Dry weight 102 ± 5

Width 740 mm

Length 1755 mm

Wheel base 1290 mm.

Overall height 1140 mm

WEIGHT AND DIMENSIONS

CHAR - 3

Characteristics LX 4tempi

Engine

ENGINE

Specification Desc./Quantity

Type Single-cylinder, 4-stroke, Piaggio Hi-Per 4
Bore 39 mm

Stroke 41,8 mm

Cubic capacity 49.93 cm³

Compression ratio 11,5 ÷ 12 : 1

Timing system single overhead camshaft, driven by a chain to the

left side.

Vacuum-type carburettor KEIHIN CVK Ø 18 mm

CO adjustment 3.2% ± 0.5

Engine idle speed 1900 ÷ 2000 rpm

Air filter Sponge impregnated with fuel mixture (50% SE-

LENIA air filter oil and 50% unleaded petrol).

Starting system electric starter/kickstarter

Lubrication engine lubrication with lobe pump (in the crank-

case) driven by a chain. Mesh prefilter and centri-

fugal on the crankshaft

Fuel supply Gravity feed, with unleaded petrol (with a minimum

octane rating of 95) with carburettor.

Max. power (crankshaft) 2,5 KW (3,4 CV) at 6500 rpm.

Cooling system forced coolant circulation system

Valve clearance (cold engine) intake 0.10 mm

CHAR - 4

LX 4tempi Characteristics

Specification Desc./Quantity

discharge 0.15 mm

Transmission

TRANSMISSION

Specification Desc./Quantity

Transmission With automatic expandable pulley variator, torque

server, V belt, automatic clutch, gear reduction

unit.

Capacities

CAPACITY

Specification Desc./Quantity

Fuel tank (including 2 litre reserve) ~ 8,5 l

Rear hub oil 85 cc

Engine oil ~ 850 cc

Electrical system

ELECTRICAL SYSTEM:

Specification Desc./Quantity

Type of ignition Capacitive discharge type electronic ignition, with

incorporated high voltage coil

Ignition advance variable, with microprocessor

(before T.D.C.)

Spark plug NGK CR 8EB

Battery 12V-9Ah

Fuse 10A

Generator single-phase alternating current

8° at 1000 + 2000 rpm - 21° at 4000 + 7000 rpm

Frame and suspensions

FRAME AND SUSPENSIONS

Specification Desc./Quantity

Type Unitised body made of stamped plate

Front suspension Single arm suspension with swinging arm articu-

lated to the steering tube. Hydraulic double-acting

shock absorber and coaxial spring

Front suspension stroke 70 mm

Trail (suspension rebounded/compressed) 71/68 mm

Rear suspension Single hydraulic double-acting shock absorber,

helicoidal coaxial spring. Chassis engine support

with swinging arm.

Rear suspension travel: 83.5 mm

Brakes

CHAR - 5

Characteristics LX 4tempi

Wheels and tyres

WHEELS AND TYRES

Specification Desc./Quantity

Front tyre size 110/70"-11"

Rear tyre size 120/70-10"
Front tyre pressure 1.6 bar
Rear tyre pressure: 2 bar

Light alloy rims (Front rim) 2.50" x 11"

Light alloy rims (rear rim) 3.00 x 10"

N.B.

CHECK AND ADJUST TYRE PRESSURE WITH TYRES AT AMBIENT TEMPERATURE. ADJUST
PRESSURE ACCORDING TO THE WEIGHT OF THE RIDER AND ACCESSORIES.

Carburettor

50cc Version

Kehin

Throttle valve diameter: Ø 18,5

Maximum air thrust (on body) Ø1,1

Marking on conical needle: NGBA

Idle air jet (on body): Ø 1,4

Initial opening - idle mixture screw: 1 3/4

Starter air nozzle (on the body): Ø 1.5

Choke needle travel: 11,5 mm

KEHIN CARBURETTOR

Specification Desc./Quantity

Type CVK 18

Choke diameter Ø 17

Marking on body: Z61B

Maximum thrust 75

Throttle spring: 100 ÷ 159 gr

Minimum thrust 35

Starter jet 40

Tightening Torques

Name Torque in Nm

Upper steering ring nut 30 ÷ 40
Lower steering ring nut 8 ÷ 10

Handlebar fastening screw 50 ÷ 55 Nm

CHAR - 6

STEERING

LX 4tempi Characteristics

FRAME ASSEMBLY

Name Torque in Nm

Engine-swinging arm bolt 33 ÷ 41

Floating arm-frame pin 44 ÷ 52

Frame-rear shock absorber nut 20 ÷ 25

Shock absorber-engine nut 33 ÷ 41

Rear wheel nut 104 ÷ 126

Speedometer gear plate fixing screw 4 ÷ 6

FRONT SUSPENSION

Name Torque in Nm

Shock absorber upper nut 20 ÷ 30

Front wheel axle nut 75 ÷ 90

Shock absorber upper bracket bolts 20 ÷ 25

Wheel rim screws 20 ÷ 25

Shock absorber lower bolts (°) 20 ÷ 27

(°)Tighten these two bolts after tightening the shock absorber central upper nut.

N.B.

FOR INFORMATION ON SAFETY TIGHTENINGS, REFER TO CHAPTER «PRE-CONSIGNMENT
CHECKS».

FRONT BRAKE

Name Torque in Nm

Brake fluid pump-hose fitting 8 ÷ 12

Brake fluid pipe-calliper fitting 20 ÷ 25

Screw tightening calliper to the support 20 ÷ 25

Brake disc screw 5 ÷ 6.5

Oil bleed valve (on the calliper) 10 ÷ 12

Handlebar pump 7 ÷ 10

ENGINE ASSEMBLY

Name Torque in Nm

Spark plug: 10 ÷ 15 Nm

Screw fixing floating head 6 ÷ 7

Head-cylinder stud bolt nuts 6 ÷ 7 + 90° + 90° *

Screws fixing head and cylinder to crankcase 8 ÷ 10

Chain tightener pad screw 5 ÷ 7 Nm

Timing chain tensioner central screw 5 - 6

Camshaft pulley screw 12 ÷ 14

Rocking lever axle and camshaft bearing screw 3 ÷ 4 Nm

Rocker-arm adjusting nuts: 7 ÷ 9 Nm

Engine oil pre-filter cover: 25 ÷ 28 Nm

Engine oil drainage cap 25 ÷ 28

Flywheel nut 40 to 44 N.m

Stator screws 3 ÷ 4

Pick-up screws 3 ÷ 4

Oil pump bulkhead screw 4 ÷ 5

Timing chain/oil pump compartment cover screws 4 ÷ 5

Oil decantation labyrinth sheet screws 7 ÷ 8

Oil pump crown screw 8 ÷ 10

Screws fixing oil pump to the crankcase 5 - 6

Oil sump screws 8 ÷ 10 Nm

CHAR - 7

Characteristics LX 4tempi

Name Torque in Nm

Inlet manifold screw 7 ÷ 9

Manifold/carburettor clamp screw 1,2 ÷ 1,5

Screws fixing cables to starter 1.5 ÷ 2.5

Starter motor screws 11 ÷ 13

Transmission cover screws 11 ÷ 13

Start-up lever screw 11 ÷ 13

Crankcase cooling cover screw 2 ÷ 2.5

Clutch assembly nut 55 ÷ 60

Crankshaft pulley nut 18 to 20 + 90° N.m

Driven pulley shaft nut 40 to 44 Nm
Hub oil drainage screw 3 ÷ 5 Nm
Rear hub cover screws 11 ÷ 13

Half casing union screw 8 ÷ 10
*When new stud bolts are assembled, tighten them with 3 turns at 90° after the first tightening at 6-7
N·m, therefore 6-7 N·m + 90 ° + 90 ° + 90 °, in a crosswise manner.

Overhaul data

Assembly clearances

Cylinder - piston assy.

Name Initials Cylinder Piston Play on fitting

Cylinder (with asso

piston/right way)

Cylinder (with shir-

am piston)

Cylinder (with asso

piston/right way)

CHAR - 8

CONNECTION PISTON AND CYLINDER

A 38,993 ÷ 39,000 38,954 ÷ 38,961 0.032 ÷ 0.046
A 38,993 ÷ 39,000 38,949 ÷ 38,956 0.037 ÷ 0.051
B 39,000 ÷ 39,007 38,961 ÷ 38,968 0.032 ÷ 0.046

LX 4tempi Characteristics

Name Initials Cylinder Piston Play on fitting

Cylinder (with shir-

am piston)

Asso piston/right

way (with asso cyl-

inder/right way)

Asso piston/right

way (with shiram

cylinder)

Shiram piston (with

asso cylinder/right

way)

Shiram piston (with

shiram cylinder)
Cylinder first uprat. A1 39,193 ÷ 39,200 39,154 ÷ 39,161 0,032 ÷ 0,046
Cylinder first uprat. B1 39,200 ÷ 39,207 39,161 ÷ 39,168 0,032 ÷ 0,046

Piston first uprat. C1 39,207 ÷ 39,214 39,168 ÷ 39,175 0,032 ÷ 0,046
Piston first uprat. D1 39,214 ÷ 39,221 39,175 ÷ 39,182 0,032 ÷ 0,046

Cylinder second

uprat.

Cylinder second

uprat.

Piston second up-

rat.

Piston second up-

rat.

Cylinder third up-

rat.

Cylinder third up-

rat.
Piston third uprat. C3 39,607 ÷ 39,614 39,568 ÷ 39,575 0,032 ÷ 0,046
Piston third uprat. D3 39,614 ÷ 39,621 39,575 ÷ 39,582 0,032 ÷ 0,046

B 39,000 ÷ 39,007 38,956 ÷ 38,966 0.037 ÷ 0.051
C 39,007 ÷ 39,014 38,968 ÷ 38,975 0,032 ÷ 0,046

C 39,007 ÷ 39,014 38,963 ÷ 38,970 0,037 ÷ 0,051

D 39,014 ÷ 39,021 38,975 ÷ 38,982 0,032 ÷ 0,046

D 39,014 ÷ 39,021 38,970 ÷ 38,977 0,037 ÷ 0,051

A2 39,393 ÷ 39,400 39,354 ÷ 39,361 0,032 ÷ 0,046
B2 39,400 ÷ 39,407 39,361 ÷ 39,368 0,032 ÷ 0,046
C2 39,407 ÷ 39,414 39,368 ÷ 39,375 0,032 ÷ 0,046
D2 39,414 ÷ 39,421 39,375 ÷ 39,382 0,032 ÷ 0,046
A3 39,593 ÷ 39,600 39,554 ÷ 39,561 0,032 ÷ 0,046
B3 39,600 ÷ 39,607 39,561 ÷ 39,568 0,032 ÷ 0,046

Piston rings

UPRATING TABLE

Name Description Dimensions Initials Quantity

1° Compression

lining

2° Compression

lining

Scraper ring lining 39 x 2 A 0,20 ÷ 0,70

39 x 1 A 0,08 ÷ 0,20
39 x 1 A 0,05 ÷ 0,20

CHAR - 9

Characteristics LX 4tempi

Name Description Dimensions Initials Quantity

1° Compression
lining 1° greater
2° Compression
lining 1° greater

Scraper ring lining

1° greater
1° Compression
lining 2° greater
2° Compression
lining 2° greater

Scraper ring lining

2° greater

1° Scraper ring lin-

ing 3° greater

2° Scraper ring lin-

ing 3° greates

Scraper ring lining

3° greates

39,2 x 1 A 0,08 ÷ 0,20
39,2 x 1 A 0,05 ÷ 0,20
39,2 x 2 A 0,20 ÷ 0,70
39,4 x 1 A 0,08 ÷ 0,20
39,4 x 1 A 0,05 ÷ 0,20
39,4 x 2 A 0,20 ÷ 0,70
39,6 x 1 A 0,08 ÷ 0,20
39,6 x 1 A 0,05 ÷ 0,20
39,6 x 2 A 0,20 ÷ 0,70

Crankcase - crankshaft - connecting rod

END PLAY BETWEEN DRIVING SHAFT AND CONNECTING ROD

Name Description Dimensions Initials Quantity

Transmission side

half shaft

Flywheel side half

shaft

Connecting rod 14.8 +0.05 -0 C

CHAR - 10

14 +0 -0.005 A
16 +0 -0.005 B

LX 4tempi Characteristics

Name Description Dimensions Initials Quantity

Spacing tool 45,00 / assembly

games D = 0,15 ÷

0,30

Slot packing system

N.B.

MEASUREMENT "A" TO BE TAKEN IS A VALUE OF PISTON RE-ENTRY, IT INDICATES BY HOW
MUCH THE PLANE FORMED BY THE PISTON CROWN FALLS BELOW THE PLANE FORMED BY
THE TOP OF THE CYLINDER. THE FURTHER THE PISTON GETS INSIDE THE CYLINDER, THE
THINNER THE HEAD GASKET TO BE APPLIED SHOULD BE (TO RECOVER THE COMPRESSION
RATIO) AND VICE VERSA.

Characteristic

Shimming system to control the compression ratio

CR: 11.1 ÷ 12.9

PISTON PROTRUSION CHECK

Name Measure A Thickness

shimming_1 0.05 ÷ 0.25 0.35
shimming_2 0.25 ÷ 0.40 0.25

E

N.B.

MEASUREMENT "A" TO BE TAKEN IS A VALUE OF PISTON RE-ENTRY, IT INDICATES BY HOW
MUCH THE PLANE FORMED BY THE PISTON CROWN FALLS BELOW THE PLANE FORMED BY
THE TOP OF THE CYLINDER. THE FURTHER THE PISTON GETS INSIDE THE CYLINDER, THE
THINNER THE HEAD GASKET TO BE APPLIED SHOULD BE (TO RECOVER THE COMPRESSION
RATIO) AND VICE VERSA.

Characteristic

CHAR - 11

Characteristics LX 4tempi

Shimming system to control the compression ratio

CR: 11.1 ÷ 12.9

PISTON PROTRUSION CHECK

Name Measure A Thickness

shimming_1 0.05 ÷ 0.25 0.35
shimming_2 0.25 ÷ 0.40 0.25

Products

TABLE OF RECOMMENDED PRODUCTS

Product Description Specifications

AGIP ROTRA 80W-90 Rear hub oil SAE 80W/90 Oil that exceeds the

requirements of API GL3 specifi-

cations

AGIP CITY HI TEC 4T Oil to lubricate flexible transmis-

sions (brakes, throttle control

and odometer)

AGIP FILTER OIL Oil for air filter sponge Mineral oil with specific additives

AGIP CITY HI TEC 4T Engine oil SAE 5W-40, API SL, ACEA A3,

AGIP GREASE MU3 Grease for odometer transmis-

sion gear case

AGIP BRAKE 4 Brake fluid FMVSS DOT4 Synthetic fluid

CHAR - 12

Oil for 4-stroke engines

for increased adhesiveness

JASO MA Synthetic oil

Soap-based lithium grease with

NLGI 3; ISO-L-XBCHA3, DIN

K3K-20

LX 4tempi Characteristics

Product Description Specifications

MONTBLANC MOLYBDENUM

GREASE

AGIP GREASE PV2 Grease for steering bearings,

AGIP GP 330 Grease for brake levers, throttle White calcium complex soap-

Grease for driven pulley shaft ad-

justing ring and movable driven

pulley housing

bolt seatings for swinging arms

and contact surface of driven pul-

ley spring (only pulley side)

Molybdenum disulphide grease

Lithium soap and zinc oxide

grease NLGI 2; ISO-L-XBCIB2

based spray grease with NLGI 2;

ISO-L-XBCIB2

CHAR - 13

Characteristics LX 4tempi

CHAR - 14

INDEX OF TOPICS

TOOLING TOOL

Tooling LX 4tempi

TOOLING

Stores code Description

001467Y008 Pliers to extract 17 mm ø bear-

ings

001467Y029 Bell for bearings, O.D. 38 mm

004499Y Bearing extractor. Fitted with: 1

Bell, 2 Sleeve, 3 Screw, 6 Ring,

27 Half rings, 34 Half rings

005095Y Engine support

008119Y009 Tube to assemble shafts and

axles

TOOL - 2

LX 4tempi Tooling

Stores code Description

020004Y Punch for removing fifth wheels

from headstock

020055Y Wrench for steering tube ring nut

020074Y Tool to align crankshaft
020150Y Air heater support

020151Y Air heater

020162Y Flywheel extractor

020171Y Punch for driven pulley roller

bearing

TOOL - 3

Tooling LX 4tempi

Stores code Description

020265Y Bearing fitting base

020288Y Fork to assemble piston on cyl-

inder

020291y Valves assembly/disassembly

tool

020306Y Punch for assembling valve seal

rings

020329Y MityVac vacuum-operated pump

TOOL - 4

LX 4tempi Tooling

Stores code Description

020330Y Stroboscopic light for timing con-

trol

020331Y Digital multimeter

020332Y Digital rev counter

020333Y Single battery charger

020334Y Multiple battery charger

TOOL - 5

Tooling LX 4tempi

Stores code Description

020335Y Magnetic support for dial gauge

020340Y Flywheel and transmission oil

seals fitting punch

020358Y 37x40-mm adaptor
020359Y 42x47-mm adaptor

020360Y Adaptor 52 x 55 mm

020362Y 12 mm guide

TOOL - 6

LX 4tempi Tooling

Stores code Description

020363Y 20 mm guide

020364Y 25-mm guide

020376Y Adaptor handle

020431Y Valve oil seal extractor

020432Y Tool to fit the start-up sector

spring

TOOL - 7

Tooling LX 4tempi

Stores code Description

020439Y 17 mm guide

020444Y Test probe removal / fitting tool
020448Y Pin lock fitting tool

020449Y Piston position check support

020450Y Camshaft fitting/removal tool

TOOL - 8

020451Y Drive pulley stop wrench

LX 4tempi Tooling

Stores code Description

020452Y Tube for removing and refitting

the driven pulley shaft

020456Y Ø 24 mm adaptor

020565Y Flywheel lock calliper spanner

494929Y Exhaust fumes analyser

TOOL - 9

Tooling LX 4tempi

TOOL - 10

INDEX OF TOPICS

MAINTENANCE MAIN

Maintenance LX 4tempi

Maintenance chart

AFTER 1,000 KM OR 4 MONTHS

90'

Action

Hub oil - change
Valve clearance - check
Idle speed (*) - adjustment
Throttle lever - adjustment
Steering - adjustment
Brake control levers - greasing
Brake pads - check condition and wear
Brake fluid level - check
Safety locks - check
Electrical system and battery - check
Tyre pressure - check
Vehicle and brake test - road test

(*) See instructions in «Idle speed adjustment» section

AT 6000 KM OR 12 MONTHS, 18000, 30000, 42000, 54000 AND 66000 KM

60'

Engine oil - replacement
Hub oil level - check
Spark plug / electrode gap - check
Oil filter (net filter) - clean
Variable speed rollers - check or replacement
Brake pads - check condition and wear
Brake fluid level - check
Electrical system and battery - check
Tyre inflation and wear - Check
Vehicle and brake test - road test

EVERY 12000 OR 24 MONTHS AND AT 60000 KM

Engine oil - replacement
Hub oil level - check
Spark plug / electrode gap - check / replacement
Air filter - clean
Oil filter (net filter) - clean
Idle speed (*) - adjustment
Throttle lever - adjustment
Variable speed rollers - check or replacement
Driving belt - replacement
Odometer cable - greasing
Steering - adjustment
Brake control levers - greasing
Brake pads - check condition and wear
Brake fluid level - check
Transmission elements - lubrication
Emergency blockings (°) - Check
Suspensions - check

Action

Action

MAIN - 2

LX 4tempi Maintenance

Action

Electrical system and battery - check
Headlight - adjustment
Tyres condition and wear - Check
Tyre pressure - check
Vehicle and brake test - road test

(*) Refer to rules (Check to CO)
(°) Refer to predelivery operations

EVERY 24000 KM OR 48000 KM

Action

Engine oil - replacement
Hub oil level - check
Spark plug / electrode gap - check / replacement
Air filter - clean
Oil filter (net filter) - clean
Valve clearance - check
Idle speed (*) - adjustment
Throttle lever - adjustment
Variable speed rollers - check or replacement
Driving belt - replacement
Cylinder ventilation system - check
Odometer cable - greasing
Steering - adjustment
Brake control levers - greasing
Brake pads - check condition and wear
Brake fluid level - check
Transmission elements - lubrication
Emergency blockings (°) - Check
Suspensions - check
Electrical system and battery - check
Headlight - adjustment
Tyres condition and wear - Check
Tyre pressure - check
Vehicle and brake test - road test

(*)Refer to rules (Check to CO)
(°) Refer to predelivery operations.

EVERY 36000

Action

Engine oil - replacement
Hub oil level - check
Spark plug / electrode gap - check / replacement
Air filter - clean
Oil filter (net filter) - clean
Idle speed (*) - adjustment
Throttle lever - adjustment
Variable speed rollers - check or replacement
Driving belt - replacement
Odometer cable - greasing
Steering - adjustment
Brake control levers - greasing
Brake pads - check condition and wear
Brake fluid hoses - replacement

MAIN - 3

Maintenance LX 4tempi

Action

Brake fluid level - check
Transmission elements - lubrication
Emergency blockings (°) - Check
Suspensions - check
Electrical system and battery - check
Headlight - adjustment
Tyres condition and wear - Check
Tyre pressure - check
Vehicle and brake test - road test

(*)Refer to rules (Check to CO)
(°) Refer to predelivery operations.

EVERY 72000

Action

Engine oil - replacement
Hub oil level - check
Spark plug / electrode gap - check / replacement
Air filter - clean
Oil filter (net filter) - clean
Valve clearance - check
Idle speed (*) - adjustment
Throttle lever - adjustment
Variable speed rollers - check or replacement
Driving belt - replacement
Cylinder ventilation system - check
Odometer cable - greasing
Steering - adjustment
Brake control levers - greasing
Brake pads - check condition and wear
Brake fluid hoses - replacement
Brake fluid level - check
Transmission elements - lubrication
Emergency blockings (°) - Check
Suspensions - check
Electrical system and battery - check
Headlight - adjustment
Tyres condition and wear - Check
Tyre pressure - check
Vehicle and brake test - road test

(*)Refer to rules (Check to CO)
(°) Refer to predelivery operations.

Brake fluid - change

10'

Engine oil - level check/ top-up

MAIN - 4

EVERY 2 YEARS

Action

EVERY 3,000 KM

Action

LX 4tempi Maintenance

Carburettor

- Disassemble the carburettor in its parts, wash all
of them with solvent, dry all body grooves with
compressed air to ensure adequate cleaning.

- Check carefully that the parts are in good condi­tion.

-The throttle valve should move freely in the
chamber. Replace valve in case of wear due to
excessive clearance.

- If there are wear marks in the chamber causing
inadequate tightness or a free valve slide (even if
it is new), replace the carburettor.

- It is advisable to replace the gaskets at every refit.

WARNING

PETROL IS HIGHLY EXPLOSIVE ALWAYS RE­PLACE THE GASKETS TO AVOID PETROL
LEAKS

1. Needle valve - 2. Idle speed adjustment screw - 3. Max jet - 4. Accelerating pump - 5. Tapered pin -

6. Jet holder - 7. Float - 8. Tank - 9. Starter device - 10. Vacuum valve - 11. Cover - 12. Minimum jet.

Checking the spark advance

The vehicle is provided with a variable spark advance electronic device. Two reference marks for the
timing can be found on the flywheel cover as to find out with more precision the reference mark on the
fan. To check, use a stroboscopic gun Tecnotest 130/P or similar type. Start the engine and let it run
at 1900 revs/min, act on the phase shifter to align the reference mark on the flywheel fan in between
the two reference marks on the casing; at the same time, read the spark advance value on the strobo­scopic gun display. The value should be 10°.
Repeat the above operation with engine running at 5000-6000 revs/min, spark advance should be 26°.

CAUTION

SHOULD THE FLASH INDICATIONS BE UNSTABLE AND THE RPM INDICATION DOES NOT
CORRESPOND WITH THE TRUE ENGINE SPEED VARIATION (FOR EXAMPLE, VALUES SHOWN
ARE HALVED), INSTALL A 10 ÷ 15 KΩ RESISTIVE CABLE CONNECTED IN SERIES TO AN HV
CABLE. IF THE IRREGULAR READING CONTINUES AFTER THIS OPERATION, CHECK THE
COMPONENTS OF THE IGNITION SYSTEM.

N.B.

WHEN THE INDUCTION CLAMP READS THE SIGNAL CORRECTLY, A READING CAN BE CAR­RIED OUT AT OVER 6000 RPM.

MAIN - 5

Maintenance LX 4tempi

RPM LIMITER

Specification Desc./Quantity

1 spark out of 7 8200 Revs/min
1 spark out of 3 8300 Revs/min

Suppression of all sparks 8500 Revs/min

Spark plug

The central electrode of the above spark plug is treated with silicone oil that acts as an antioxidant
agent. If the silicone oil is in excess, crystals tend to form and, by causing hot fire points to preignition
phenomena, tend to reduce the spark plug performance. This results in difficulties for vehicles to reach
the maximum speed and anomalous noises.
If the above situation should occur, replace the spark plug before performing any other intervention.
Before installing the new spark plug, blow with air to remove the silicone oil in excess.
Direct the jet of compressed air into the round groove between the threaded metal part and the ceramic
part of the inner electrode while turning the spark plug to allow removal of the oil in excess.

MAIN - 6

LX 4tempi Maintenance

Detach the spark plug cap and then remove the
spark plug.

- Carefully examine the spark plug, and replace it
if the insulator is damaged or chipped.

- With the aid of a feeler gauge, measure the spark
gap and, if necessary, adjust by bending outer
electrode with care.

- Ensure the sealing washer is in good conditions.

- Refit the spark plug by engaging the thread man­ually and then tightening it to the prescribed torque
using the box-spanner provided.

Characteristic

Electrode gap

0.7 ÷ 0.8 mm

Spark plug

NGK CR 8EB

Locking torques (N*m)

Spark plug 10 ÷ 15 Nm

Hub oil

Check

- Place the vehicle on the stand on level ground.

- Unscrew oil dipstick «A», wipe it with a clean rag,
reinsert it and screw it in fully.

- Pull out the dipstick and check that the oil level is
in the middle (two-notch dipstick) or reaches the
middle notch (three-notch dipstick).

- Reinsert the dipstick and screw it in fully.

Recommended products

AGIP ROTRA 80W-90 rear oil hub

SAE 80W/90 Oil that exceeds the requirements of
API GL3 specifications

MAIN - 7

Maintenance LX 4tempi

Replacement

- Remove oil filler cap/dipstick «A».

- Unscrew the drain plug «B» shown in the figure
and allow the oil to drain out.

- Retighten the drain plug and fill the hub with oil
(about 100 cc).

Air filter

After removing the lower part of the left-hand side
cover, unscrew the four fixing screws and the two
knobs (which are exposed by overturning the sad­dle and removing the helmet compartment), re­move the filter cover and then pull out the filter
cartridge.
Cleaning:

-Wash the filter with soap and water.

-Dry with a clean cloth without wringing and with
compressed air.

-Soak with a 50% fuel-oil mixture.

-Let the filter cartridge drip and then squeeze it
between the hands without wringing.

CAUTION

NEVER RUN THE ENGINE WITHOUT THE AIR
FILTER, THIS WOULD RESULT IN AN EXCES­SIVE WEAR OF THE PISTON AND CYLINDER.

Engine oil

MAIN - 8

LX 4tempi Maintenance

Replacement

-Loosen the oil filler plug.

-Unscrew the gauze strainer drain plug on the fly­wheel side and allow the oil to drain completely.

-Retighten the drain plug and pour in approximate­ly 600-650 cc of oil.

Check

Rest the vehicle (with the engine cold) on its centre
stand on flat ground.

-Ensure the oil level is between the MAX and MIN
marks on the dipstick.

-The MAX mark implies a quantity of ~ 850 cc of
oil in the engine.

-If the oil level approaches the MIN mark, top up
with fresh oil without ever exceeding the MAX
mark.

Recommended products

AGIP CITY HI TEC 4T Oil to lubricate flexible
transmissions (brakes, throttle control and od­ometer)

Oil for 4-stroke engines

Engine oil filter

- Change the oil when the engine is warm.

- Place a container under the oil sump and remove
the cap for draining the oil.

- After draining the oil clean the mesh filter with a
specific solvent and then blow it down with com­pressed air.

- The latter is accessible by removing the cap
«A» (see figure).

MAIN - 9

Maintenance LX 4tempi

- After this operation refit the filter and tighten the
oil cap to the sump using a new O-ring.

- Fill the engine oil through the hole located on the
oil sump.

- Engine oil capacity: ~ 850 cc.

- Manually tighten cap.

N.B.

RUN THE ENGINE FOR A FEW MINUTES THEN
RECHECK THE ENGINE OIL LEVEL WHEN THE
ENGINE IS COLD, IT MUST ALWAYS REMAIN
UNDER THE MAX LEVEL.

N.B.

IF FILLING FOR THE 1ST TIME OR FOR OVER­HAUL ADD 850 C.C. OF ENGINE OIL, IN OTHER
CASES 650 C.C. AND FILL UP IF NECESSARY.

Recommended products

AGIP CITY HI TEC 4T Engine oil

SAE 5W-40 Synthetic oil that exceed the require­ments of API SL, ACEA A3, JASO MA specifica­tions

Locking torques (N*m)

Engine oil pre-filter cover 25 ÷ 28 Nm

Checking the ignition timing

- Turn the flywheel clockwise until its 2nd notch
coincides with the Pick-up reference mark as
shown in the figure.
Make sure that the reference point on the camshaft
command crown is aligned with the reference point
on the head as shown in the second figure.
If the reference is opposite the indicator on the
head, turn the crankshaft once more as the piston
must be at the TDC of the bursting phase.

N.B.

TIME THE TIMING SYSTEM UNIT AS DESCRI­BED IN CHAPTER 6 IF IT IS NOT IN PHASE

MAIN - 10

LX 4tempi Maintenance

Checking the valve clearance

- Remove the spark plug access cover, undo the
4 fixing screws indicated in the figure and remove
the tappet cover.

- To check valve clearance, centre the reference
marks of the timing system point as described
above.

- Use an adequate thickness gauge to check that
the clearance between the valve and the register
corresponds with the indicated values.
Should the valve clearance values, intake and
drainage respectively, be different from the ones
indicated below, adjust them by loosening the lock
nut and operate on the register with a screwdriver
as shown in the figure.

Characteristic

Intake (with cold engine)

0.10 mm

Drainage (with cold engine)

0.15 mm

Headlight adjustment

Proceed as follows:

1. Place the vehicle in running order and with the
tyres inflated to the prescribed pressure, on a flat
surface 10 m away from a white screen situated in
a shaded area, making sure that the longitudinal
axis of the scooter is perpendicular to the screen;

2. Turn on the headlight and check that the bor­derline of the projected light beam on the screen
is not lower than 9/10 of the distance from the
ground to the centre of vehicle headlamp and high­er than 7/10;

3. If otherwise, adjust the right headlight with screw
«A».

N.B.

MAIN - 11

Maintenance LX 4tempi

THE ABOVE PROCEDURE COMPLIES WITH
THE EUROPEAN STANDARDS REGARDING
MAXIMUM AND MINIMUM HEIGHT OF LIGHT
BEAMS. REFER TO THE STATUTORY REGU­LATIONS IN FORCE IN EVERY COUNTRY
WHERE THE vehicle IS USED.

SAS filters inspection and cleaning

Use the two screws "A" on the right side panel and
remove it. Use the three screws "B" to remove the
cover of the secondary air box. Move the cover of
the box away and remove the sponge filter "C".
Wash the sponge with water and a neutral soap,
and dry it with a clean rag and shorts blasts of
compressed air. When cleaning the filter, make
sure the reed valve "D" is in good condition then
reinsert it in its seat on the box.
Before closing the SAS box cover, check the con­dition of the O-ring seal; replace it if it appears
damaged or deformed.

N.B.

The reed valve can be inserted in only one di­rection on the SAS housing

MAIN - 12

INDEX OF TOPICS

TROUBLESHOOTING TROUBL

Troubleshooting LX 4tempi

Engine

Poor performance

POOR PERFORMANCE

Possible Cause Operation

Air filter clogged or dirty Disassemble, wash sponge with water and sham-

poo and immerse in a mixture of 50% petrol and

Selenia Air Filter oil. Let it drip. Wring out without

squeezing it and then refit

Carburettor nozzles clogged or dirty Dismantle, wash with solvent and dry with com-

pressed air

Dirty or faulty vacuum-operated cock Check the filter on the cock, remove the petrol and

wash the tank, if necessary. Replace the cock as

a last resource.

Clutch slipping Check the clutch system and/or the bell and re-

place if necessary

Inefficient automatic transmission Check the rollers and the pulley movement, re-

place the damaged parts and lubricate the driven

pulley moveable guide with Montblanc Molybde-

num Grease

Lack of compression parts, cylinder and valves

wear

Oil level exceeds maximum Check for causes and fill to reach the correct level

Excess of encrustations in the combustion cham-

ber

Timing failure or timing system parts worn Reset timing phase or replace any worn parts (re-

Muffler obstructed Replace

Fuel filter on vacuum operated cock blocked Clean the cock filter

Wrong valve adjustment Adjust the valve clearance properly

Valve seat distorted Replace the head assembly

Worn cylinder, Worn or broken piston rings Replace the piston cylinder assembly or just the

Descale the cylinder, the piston, the head and the

Replace the worn parts

valves

fer to 4-stroke 50 cc engine manual)

piston rings

Rear wheel spins at idle

Possible Cause Operation

Idling rpms too high Check the idling speed and, if necessary, adjust

Clutch fault Check the spring/friction mass and the clutch bell

Air filter housing not sealed Correctly refit the filter housing and replace it if it

Purifier-carburettor fitting damaged Replace

TROUBL - 2

REAR WHEEL

the C.O.

is damaged

LX 4tempi Troubleshooting

Starting difficulties

STARTING PROBLEMS

Possible Cause Operation

Defective spark plug or with incorrect electrode

gap

Battery flat Check the state of the battery. If it shows signs of

- Engine flooded. Start up keeping the throttle fully open alternating

Vacuum operated cock failure Check that fuel is adequately supplied through the

Failing automatic starter on the carburettor Check the electrical wiring and mechanical move-

Wrong ignition advance Check flywheel keying on the crankshaft, replace

Incorrect valve sealing or valve adjustment Inspect the head and/or restore the correct clear-

Starting rpm too low. Starter motor faulty. Check starting motor.

Altered fuel characteristics Drain off the fuel no longer up to standard; then,

Carburettor nozzles clogged or dirty Dismantle, wash with solvent and dry with com-

Check and if necessary replace the spark plug and

the electrode gap

sulphation replace it and bring the new battery into

service charging it for eight hours at a current of

1/10 of the capacity of the battery itself

approximately five seconds of turning it with five

seconds still. If however it does not start, remove

the spark plug, the engine over with the throttle

open being careful to keep the cap in contact with

the spark plug and the spark plug grounded but

away from its hole. Refit a dry spark plug and start

the vehicle.

pipe by applying a vacuum to the suction pipe

ment, replace if necessary.

control unit if necessary

ance

refill

pressed air

Engine tends to cut-off at full throttle

ENGINE TENDS TO CUT OUT AT FULL THROTTLE

Possible Cause Operation

Maximum jet clogged Remove the carburettor, wash with solvent and dry

with compressed air

Water or condensate in the carburettor tank Remove the tank, wash with solvent and dry with

compressed air or empty the tank through the ap-

propriate bleed screw

Incorrect ignition advance Use a stroboscopic light to check ignition advance

and the flywheel correct keying

Air filter blocked or dirty. Dismantle the sponge, wash with water and sham-

poo, then soak it in a mixture of 50% petrol and

50% of specific oil (Selenia Air Filter Oil), then

hand dry without squeezing, allow to drip dry and

then reassemble.

Incorrect float level Restore the correct level in the tank (the float must

be parallel to the upper cover contact plane, that

is the throttle valve membrane cover)

Fuel supply pipes choked or clogged Restore the adequate fuel supply

Tank breather hole obstructed Restore the proper tank aeration

TROUBL - 3

Troubleshooting LX 4tempi

Possible Cause Operation

Level in tank too low Restore the correct level in the tank (the float must

be parallel to the upper cover contact plane, that

is the throttle valve membrane cover)

Engine tends to cut-off at idle

ENGINE TENDS TO STOP WHEN IDLING

Possible Cause Operation

Air calibrated holes in carburettor blocked Dismantle, wash with solvent and dry with com-

pressed air

Defective floating valve Check the proper sliding of the float and the func-

tioning of the valve

Level in tank too high Restore the correct level in the tank (the float must

be parallel to the upper cover contact plane, that

is the throttle valve membrane cover)

Automatic choke stays activated Check that the piston slides freely and that fuel is

supplied to the automatic choke. Renew if neces-

sary

Air filter blocked or dirty. Dismantle the sponge, wash with water and sham-

poo, then soak it in a mixture of 50% petrol and

50% of specific oil (Selenia Air Filter Oil), then

hand dry without squeezing, allow to drip dry and

then reassemble.

Wrong idling adjustment Correctly adjust the engine idling and check the

level of the C.O.

Spark plug defective or faulty Replace the spark plug with one with the specified

degree and check the plug gap

Pressure too low at the end of compression Check the thermal group seals and replace worn

components

Incorrect timing Time the system and check the timing system

components

High fuel consumption

EXCESSIVE FUEL CONSUMPTION

Possible Cause Operation

Air filter blocked or dirty. Dismantle the sponge, wash with water and sham-

The starter remains on Check that the starter runs correctly and it is prop-

Loose nozzles Check the maximum and minimum nozzles are

Incorrect float level Check and restore the correct fuel level in the tank

Transmission and brakes

TROUBL - 4

poo, then soak it in a mixture of 50% petrol and

50% of specific oil (Selenia Air Filter Oil), then

hand dry without squeezing, allow to drip dry and

then reassemble.

erly powered

adequately fixed in their fittings

LX 4tempi Troubleshooting

Clutch grabbing or performing inadequately

IRREGULAR CLUTCH PERFORMANCE OR SLIPPAGE

Possible Cause Operation

Faulty clutch Check that there is no grease on the masses.

Check that the clutch mass contact surface with

the casing is mainly in the centre with equivalent

characteristics on the three masses. Check that

the clutch casing is not scored or worn in an anom-

alous way

Insufficient braking

INEFFICIENT BRAKING

Possible Cause Operation

Worn brake pads or shoes Replace the brake pads or shoes and check for

brake disk or drum wear conditions.

Air bubbles inside the hydraulic braking system Carefully bleed the hydraulic braking system,

(there must be no flexible movement of the brake

lever).

Brake disc or drum deformed Use a dial gauge to check the levelness of the disk

with the wheel correctly fitted and the concentricity
of the rear drum; check the brake disc screws are

locked

Fluid leakage in hydraulic braking system Elastic fittings, piston seals or brake pump break-

down, replace

Excessive backlash in rear brake control cable Adjust backlash with the appropriate adjuster on

the shoe control lever

The brake fluid has lost its properties Replace the front brake fluid and top up to the cor-

rect level in the pump

Return spring broken Replace spring.

Shoe control bolt not lubricated Lubricate with Z2 grease.

Brakes overheating

Possible Cause Operation

Defective sliding of pistons Check calliper and replace any damaged part.

Brake disc or drum deformed Use a dial gauge to check the levelness of the disk

Electrical system

BRAKES OVERHEATING

with the wheel correctly fitted and the concentricity
of the rear drum; check the brake disc screws are

locked

TROUBL - 5

Troubleshooting LX 4tempi

Battery

BATTERY

Possible Cause Operation

This device requires the most assiduous surveil-

lance and the most diligent maintenance.

This device requires the most assiduous surveil-

lance and the most diligent maintenance. If the

vehicle is not used for some time (1 month or

more) the battery needs to be recharged periodi­cally. The battery tends to exhaust its power sup­ply in five to six months. If the battery is fitted on a

motorcycle, be careful not to invert the connec-

tions, keeping in mind that the black earth wire is

connected to the negative terminal while the red

wire is connected to the terminal marked +.

Turn signal lights malfunction

ELECTRICAL EQUIPMENT FAILURE

Possible Cause Operation

Turn indicators do not turn on Check turn indicators device and/or wiring as de-

scribed in the «Electrical system» chapter.

Steering and suspensions

Heavy steering

Possible Cause Operation

Steering hardening Check the tightening of the top and bottom ring

Excessive steering play

EXCESSIVE STEERING CLEARANCE

Possible Cause Operation

Excessive steering backlash Check the tightening of the top ring nut. If irregu-

STEERING HARDENING

nuts. If irregularities continue in turning the steer-

ing even after making the above adjustments,

check the seats in which the ball bearings rotate:

if they are recessed or if the balls are squashed,

replace them.

larities continue in turning the steering even after
making the above adjustments, check the seats in

which the ball bearings rotate: replace if they are

recessed.

TROUBL - 6

LX 4tempi Troubleshooting

Noisy suspension

SUSPENSION NOISY

Possible Cause Operation

Noisy suspension If the front suspension is noisy, check: that the

front shock absorber works properly and the ball

bearings are good condition.

In conclusion, check the tightening torque of the
wheel hub, the brake calliper, the shock absorber
disk in the attachment to the hub and the steering

tube.
Check that the swinging arm connecting the en­gine to the chassis and the rear shock absorber

work properly

Suspension oil leakage

OIL LEAKAGE FROM SUSPENSION

Possible Cause Operation

Oil leakage from suspension Replace the damper.

TROUBL - 7

Troubleshooting LX 4tempi

TROUBL - 8

INDEX OF TOPICS

ELECTRICAL SYSTEM ELE SYS

Electrical system LX 4tempi

ELECTRICAL COMPONENTS

Specification Desc./Quantity

1 Front L.H. turn signal light
2 Front direction indicator lights 12V-10W x 2
3 Horn button
4 Indicators switch
5 Light switch
6 Rear stop switch
7 Headlight bulb 12V-35/35W
8 Front tail light bulb Type: All glass

Power: 12V 5W

Quantity: 1

9 Right turn indicator warning light 12V-2W
10 Reserve fuel light 12V-1,2W
11 left turn indicator warning light 12V-2W
12 High beam warning light bulb 12V-1,2W
13 Dashboard light bulbs Type: Bayonet

Power: 12V 1.2W

ELE SYS - 2

LX 4tempi Electrical system

Specification Desc./Quantity

Quantity: 3

14 Headlamp warning light 12V 1,2W
15 Odometer with warning lights and level

gauges
16 Front headlight
17 Front brake stop light switch
18 Starter button
19 Ignition key-switch
20 Front R.H. turn signal light
21 Fuel level sender
22 Automatic starter
23 Starter remote control
24 Rear R.H. turn signal light
25 Taillight assembly
26 Stop and tail light bulb Type: Spherical

Power: 12V 21/5W

Quantity: 1

27 Battery 12V - 9Ah
28 Control device ignition
29 Flywheel magneto
30 Starter motor
31 Fuse carrier (N° 1 fuse to 10 A)
32 Rear L.H. turn signal light
33 Rear direction indicator lights N° 2, 12V-10W, spherical
34 Voltage regulator
35 Claxon in c.c.
36 Resistance 10 Ohm - 10W

Electrical cables color:
B = White, Bl = Blu, G = Yellow, Mr = Brown, N = Black, Gr = Gray,
Rs = Pink, R = Red, Vi = Purple, V = Green

Conceptual diagrams

ELE SYS - 3

Electrical system LX 4tempi

Ignition

IGNITION

Specification Desc./Quantity

1 Magneto flywheel
2 Pick - up
3 Key switch contacts
4 Electronic ignition device
5 Fuse 10 A
6 Voltage regulator
7 Battery 12V-9Ah

Headlights and automatic starter section

ELE SYS - 4

LX 4tempi Electrical system

HEADLIGHTS

Specification Desc./Quantity

1 Magneto flywheel
2 Voltage regulator
3 Light switch
4 Headlight bulb 12V-35/35W
5 High beam warning light bulb 12V-1,2W
6 Rear light bulb 12V - 5W
7 Headlight warning light 12V - 1.2W
8 Front position light filament 12V - 5W
9 Instrument panel light bulbs Type: All glass

Power: 12V 1.2W

Quantity: 2

10 Dashboard light bulbs 12V-2W

Battery recharge and starting

BATTERY RECHARGE AND START-UP SECTION

Specification Desc./Quantity

1 Voltage regulator
2 Magneto flywheel
3 Automatic starter
4 Battery 12V-9Ah
5 Remote starter switch
6 Starter motor
7 Start up button
8 Brake light filament 12V-21W
9 Front and rear brake light button

ELE SYS - 5

Electrical system LX 4tempi

Specification Desc./Quantity

10 Key switch
11 Main fuse 10A
12 Resistance 6,8 Ohm - 10W

Level indicators and enable signals section

START PERMISSIVE BUTTONS AND LEVEL INDICATORS

Specification Desc./Quantity

1 Voltage regulator
2 Fuel Level indicator
3 Fuel level sender
4 Reserve fuel light 12V-1,2W
5 Front and rear brake light button
6 Fuse 10 A
7 Battery 12V-9Ah
8 Brake light filament 12V-21W
9 Key switch contacts

ELE SYS - 6

LX 4tempi Electrical system

Turn signal lights

TURN INDICATORS AND HORN

Specification Desc./Quantity

1 Indicators switch
2 Horn button
3 Horn
4 Two (2) turn signal warning light bulbs 12V - 2W
5 4 Turn indicator bulbs 12V-10W
6 Voltage regulator
7 Key switch contacts
8 Fuse 10 A
9 Battery 12V-9Ah

ELE SYS - 7

Electrical system LX 4tempi

Instruments and warning lights control board

WARNING LIGHTS AND GAUGES PANEL

Specification Desc./Quantity

1 left turn indicator warning light 12V-2W
2 High beam warning light bulb 12V-1,2W
3 Fuel Level indicator
4 Instrument panel lighting bulb 12V-1,2W
5 Headlamp warning light 12V 1,2W
6 Reserve fuel light 12V-1,2W
7 Right turn indicator warning light 12V-2W
8 Dashboard light bulbs 12V-2W
9 Available warning light

Checks and inspections

In case the cause of ignition failure or malfunction
cannot be easily identified at sight, first of all re­place the control unit by another one in operating
conditions.
Remember that the engine must be off to discon­nect and replace the control unit.
If after replacement the vehicle starts properly, the
control unit is failing and must be replaced.

ELE SYS - 8

LX 4tempi Electrical system

If faulty or failed operation persists, conduct the
following checks on the generator and on the sta­tor components:
After a visual inspection of the electrical connec­tions, it is possible to perform measurements on
the stator winding and pick-up (see table), using
the specific multimeter.
If, during the checks on the charge coil and the
pick-up, anomalies are found, replace the stator
and other faulty parts.
Disconnect the connector on the flywheel housing
and measure the resistance between each of the
two contacts and the earth.

Specific tooling

020331Y Digital multimeter

PICK-UP CHECK

Specification Desc./Quantity

1 1) Brown cable and earth ~ 170 Ω

STATOR WINDING CHECK

Specification Desc./Quantity

1 1) Black cable and earth ~ 1 Ω

ELE SYS - 9

Electrical system LX 4tempi

Ignition circuit

All the control operations of the system that require
the disconnection of cables (checks of the con­nections and the devices making up the ignition
circuit) must be done with the engine off: if this is
not done, the controls might be irreparably dam­aged.

Stator check

- Using a tester, check the resistance between the
brown-earth and black-earth terminal.

N.B.

VALUES ARE STATED AT AMBIENT TEMPER­ATURE. A CHECK WITH THE STATOR AT OP­ERATING TEMPERATURE LEADS TO VALUES
HIGHER THAN THOSE STATED.

Electric characteristic

Stator : Brown-earth

approx. 170 Ω (Pick-Up)

Stator : Black-earth

~ 1 Ω (Stator)

Voltage regulator check

The malfunctioning of the voltage regulator might cause the following problems depending on the type
of fault:

1) Bulbs burnt out (regulator in short circuit).

2) The lighting and electrical starter system do not work (regulator interrupted).

3) Battery fails to charge

4) Turn indicators failure
The regulator is provided with earth supplied from the electrical equipment, therefore the regulator body
does not supply earth to the internal circuits. Check the insulation between each terminal of the regulator
and its body, using the specific tester.

ELE SYS - 10

LX 4tempi Electrical system

2) LIGHTS AND CHOKE DEVICE NOT OPERA­TIONAL
Remove the plastic door on the leg-shield to reach
the voltage regulator, start the engine and let it run
at idle.
Place the positive terminal from the tester on ter­minal no. 1 (yellow-black wire) and the negative
terminal on terminal no. 2 (black wire); check for
voltage.
If voltage is present, check the wiring connecting
the headlight switch to the voltage regulator, and
the operation of the light switch.
If no voltage is found, put the negative terminal to
earth; if this provides voltage readings, check the
earth wire on the regulator; otherwise, replace the
regulator as certainly faulty.
As a last test it is possible to check the output volt­age from the stator:

-Detach the regulator connector and interpose the
tester between the Gray-Blue wire (4) and earth
(see figure).

-The voltage output at 2,000 rpm must be approx.
25 - 35V If this test gives no voltage readings too,
replace the regulator as certainly faulty.

N.B.

TO MEASURE THE ABOVE VOLTAGE USE AN
ANALOGUE TESTER THAT CAN MEASURE
ALTERNATING VOLTAGES AND KEEP THE
ENGINE AT IDLE TO HAVE AN ALTERNATING
VOLTAGE OF A FREQUENCY AS CLOSE AS
POSSIBLE TO 50HZ SO AS TO DETECT THE
EFFICIENT VOLTAGE VALUE SUPPLIED BY
THE REGULATOR (ABOUT 12V).

ELE SYS - 11

Electrical system LX 4tempi

Recharge system voltage check

3) BATTERY DOES NOT RECHARGE
The fault in the DC section of the voltage regulator
may cause, depending on the type of failure, the
following faults:

a) Bursting of protection fuse due to exces­sively high voltage (regulator short-circuited)
and resulting in the battery not recharging.
b) Battery not recharging (regulator circuit in­terrupted).
Interventions

a) Bursting of protection fuse (regulator short­circuited).
Check the wiring running from the fuse to the ig­nition key-switch is not damaged, as this may cre­ate a short-circuit with earth (thus excluding
possible regulator failures); if the protection fuse
bursts only after the ignition key-switch is turned
to "ON", and with the regulator connector detach­ed, it is then necessary to check the wirings and
systems downstream the key-switch are not short­circuited with earth.
Proceed by measuring the resistance between
contacts 3 (White) and 2 (Black) from the voltage
regulator (with the connector detached).
If the reading differs excessively from the figures
shown, replace the regulator as short-circuited.
b) Battery not recharging (regulator circuit inter­rupted).
To check for the presence of faults on the recharg­ing section of the voltage regulator, it is necessary
to initially operate on the battery, using two testers
(one for voltages and one for currents), as shown
in the second figure, and follow the operations giv­en below:
Start the engine (connecting, temporarily, the red
wire to the positive terminal of the battery, so to

ELE SYS - 12

LX 4tempi Electrical system

avoid damaging the instrument measuring the cur­rent).
Check the voltage at idle is at least 13V (charged
battery) and the recharge current is 1.5 - 2A with
the lighting system and the choke device exclu­ded, as described in the chapter "CHECKING THE
VOLTAGE REGULATOR".
As the engine speed increases, so do the recharge
current and voltage, and at speeds above 4,000
rpm, a recharging current of approx. 4.5A must be
observed; reactivating the lighting system and
choke device, and operating the stop light and
horn, current values of ≥ 5A may be found, with
voltage readings of 14 - 14.5V (regulator threshold
voltage).

If the readings do not match the above figures,
replace the regulator; otherwise check wiring
and connections.

Electric characteristic

Resistance of voltage regulator

~ 8 MΩ

Turn signals system check

4) TURN INDICATORS FAIL TO OPERATE
In case of turn indicators fault, proceed as follows:

- Remove the regulator connector and insert the
multimeter prods between white wire (3) and black
wire (2).

- Turn the key switch to ON and check that the
battery is powered. If no voltage is measured, re­peat the test between the earth and white cable. If
the check is still unsuccessful, check the cables
and the contacts on the key switch and battery. If
the battery voltage is measured, check the regu­lator earth cables (black cable)

- If the above checks are successful, jump contacts
5 (blue/black) and 3 (white) on the connector, turn

ELE SYS - 13

Electrical system LX 4tempi

the key switch to ON and turn the flashlights switch
to the left and to the right to check if lights goes on
(these are directly fed by the battery).
If the flashlights do not go on, check the cables and
the switch operation; otherwise, replace the regu­lator since it is faulty.

Specific tooling

020331Y Digital multimeter

Sealed battery

INSTRUCTIONS FOR REFRESHING THE STOCK CHARGE OF AN OPEN CIRCUIT

1) Voltage check

Before installing the battery on the vehicle, check the open circuit voltage with a normal tester.

- If the voltage exceeds 12.60 V, the battery may be installed without any renewal recharge.

- If voltage is below 12.60 V, a renewal recharge is required as explained in 2).

2) Constant voltage battery charge mode

-Constant voltage equal to 14.40÷14.70V

-Initial charge voltage equal to 0.3÷0.5 for nominal capacity

-Duration of the charge: 10 to 12 h recommended
Minimum 6 h
Maximum 24 h

3) Constant current battery charge mode

-Charge current equal to 1/10 of the nominal capacity of the battery

-Duration of the charge: 5 h

WARNING

-WHEN THE BATTERY IS REALLY FLAT (WELL BELOW 12.6V) IT MIGHT BE THAT 5 HOURS OF
RECHARGING ARE NOT ENOUGH TO ACHIEVE OPTIMAL PERFORMANCE.
IN THESE CONDITIONS IT IS HOWEVER ESSENTIAL NOT TO EXCEED EIGHT HOURS OF CON­TINUOUS RECHARGING SO AS NOT TO DAMAGE THE BATTERY ITSELF.

Dry-charge battery

WARNING

- Battery electrolyte is toxic and it may cause serious burns. It contains sulphuric acid. Avoid contact
with eyes, skin and clothing. In case of contact with eyes or skin, flush abundantly with water for about
15 minutes and seek immediate medical attention.
In the event of accidental ingestion of the fluid, immediately drink large quantities of water or milk. Follow
with milk of magnesia, beaten egg or vegetable oil. Seek immediate medical attention
Batteries produce explosive gases; keep clear of free flames, sparks or cigarettes; ventilate the area
when recharging the battery indoors.
Always protect your eyes when working close to batteries.

Keep out of the reach of children.

ELE SYS - 14

LX 4tempi Electrical system

The battery is an electrical device which requires
careful monitoring and diligent maintenance. The
maintenance rules are:

1) Check the level of the electrolyte

The electrolyte level must be checked frequently
and must reach the upper level. Only use distilled
water, to restore this level.
If it is necessary to add water too frequently, check
the vehicle's electrical system: the battery works
overcharged and is subject to quick wear.

2)Load status check

After restoring the electrolyte level, check its den­sity using an appropriate densitometer (see the
figure).
When the battery is charged, you should detect a
density of 30 to 32 Bé corresponding to a specific
weight of 1.26 to 1.28 at a temperature of no lower
than 15° C.
A density reading of less than 20° Bé indicates that
the battery is completely flat and it must therefore
be recharged.
After charging the battery, check each element
electrolyte level and density. If the scooter is not
used for a given time (1 month or more) it will be
necessary to periodically recharge the battery.
The battery runs down completely in the course of
three months.
If it is necessary to refit the battery in the vehicle,
be careful not to reverse the connections, remem­bering that the earth wire (black) marked (-) must
be connected to the - negative terminal while the
other two red wires marked (+) must be connected
to the terminal marked with the + positive sign.
Regular bench charging must be carried out with
the specific battery charger, (single) or (multiple),
setting the battery charger selector to the type of
battery to be recharged. Connections to the power

ELE SYS - 15

Electrical system LX 4tempi

supply source must be implemented by connect­ing the corresponding poles (+ to+ and - to -).

4) Cleaning the battery

The battery should always be kept clean, espe­cially on its top side, and the terminals should be
coated with Vaseline.

WARNING

- Before recharging the battery, remove the plugs
of each cell. Keep the battery away from naked
flames or sparks when charging.
Remove the battery from the vehicle removing the
negative clamp first.

CAUTION

NEVER USE FUSES WITH A CAPACITY HIGH­ER THAN THAT RECOMMENDED.
USING A FUSE OF UNSUITABLE RATING MAY
SERIOUSLY DAMAGE THE VEHICLE OR EVEN
CAUSE A FIRE.

CAUTION

DRINKING WATER CONTAINS MINERALS
THAT CAN BE EXTREMELY HARMFUL TO THE
BATTERY: USE DISTILLED WATER ONLY.

CAUTION

TO ENSURE MAXIMUM PERFORMANCE THE
BATTERY MUST BE CHARGED BEFORE USE.
INADEQUATE CHARGING OF THE BATTERY
WITH A LOW ELECTROLYTE LEVEL BEFORE
IT IS FIRST USED SHORTENS THE LIFE OF
THE BATTERY.

Specific tooling

020333Y Single battery charger
020334Y Multiple battery charger

1)- Remove the short closed tube and the caps, then pour sulphuric acid into the cells using the type
specified for batteries, with a specific gravity of 1.26, corresponding to 30° Bé, at a minimum temperature
of 15°C until the upper level is reached.

2) - Leave to rest for at least 2 hours; then, restore the level with sulphuric acid.

3)- Within the following 24 hours, recharge with the specific battery charger (single) or (multiple) at a
density of about 1/10 of the battery nominal capacity and until the acid density is about 1.27, corre­sponding to 31º Bé, and these values are stabilised.

4) - Once the charge is over, level the acid (by adding distilled water). Close and clean carefully.

5)- Once the above operations have been performed, install the battery in the vehicle ensuring the
connections between the wiring and the battery terminals are correct.

WARNING

- ONCE THE BATTERY HAS BEEN INSTALLED IN THE VEHICLE IT IS NECESSARY TO REPLACE
THE SHORT TUBE (WITH CLOSED END) NEAR THE + POSITIVE TERMINAL WITH THE CORRE-

ELE SYS - 16

LX 4tempi Electrical system

SPONDING LONG TUBE (WITH OPEN END), THAT YOU FIND FITTED TO THE VEHICLE, TO
ENSURE THAT THE GASES THAT FORM CAN ESCAPE PROPERLY.

Specific tooling

020333Y Single battery charger
020334Y Multiple battery charger

ELE SYS - 17

Electrical system LX 4tempi

ELE SYS - 18

INDEX OF TOPICS

ENGINE FROM VEHICLE ENG VE

Engine from vehicle LX 4tempi

Exhaust assy. Removal

- Remove the 2 fixing nuts from the manifold to the
head

- Unscrew the 2 screws fixing the muffler to the
housing; then remove the whole muffler paying at­tention to the interference between its supporting
bracket and the cooling cover.

Removal of the engine from the vehicle

Removing the engine from the frame

-Disconnect the battery.

-Remove the muffler assembly.

- Remove the rear wheel.

- Remove the rear brake mechanical transmission.

-Disconnect the electric terminals.

-Remove the throttle grip transmission.

- Disconnect the tubing (petrol-vacuum operated cock control).

- Disconnect the swinging arm on the engine side

- Disconnect the rear shock absorber lower clamping

WARNING

Be very careful when handling fuel.

CAUTION

When installing the battery, first attach the positive cable and then the negative cable.

WARNING

Wear safety goggles when using hitting tools.

ENG VE - 2

INDEX OF TOPICS

ENGINE ENG

Engine LX 4tempi

Automatic transmission

Transmission cover

- Remove the 12 fixing screws.

- Remove the oil filling cap and then slide out the
cover.
If this operation is carried out directly on the vehi­cle, it is necessary to remove the transmission
cooling coupling and the air filter housing retain­ers.

N.B.

USE A MALLET ON THE APPROPRIATE COU­PLINGS TO REMOVE THE COVER.

Kickstart

-To remove the start up pinion push the starter
lever to facilitate extracting the pinion.

-Remove the kick-start screw and lever.

-Remove the seeger ring and the washer indicated
in the figure.

-Pull out the toothed sector.

WARNING

THE SECTOR KEEPS THE SPRING SET, BE
CAREFUL SO AS NOT TO CAUSE ANY ACCI­DENTS

Air duct

- To remove the intake throat on the transmission
cover, just remove the three fixing screws indica­ted in the figure.

ENG - 2

LX 4tempi Engine

Removing the driven pulley shaft bearing

- Slightly heat the crankshaft from the inside side
to avoid damaging the coated surface and use the
driven pulley shaft or a pin of the same diameter
to remove the bearing.

N.B.

IN CASE OF DIFFICULTY A STANDARD 8MM­INSIDE DIAMETER EXTRACTOR CAN BE
USED.

Refitting the driven pulley shaft bearing

Refit the bearing with the aid of a bushing with the same diameter as the external plate of the bearing
after slightly heating the crankcase from the inside.

N.B.

WHEN REFITTING, ALWAYS REPLACE THE BEARING WITH A NEW ONE.

CAUTION

WHEN REMOVING/REFITTING THE BEARING, TAKE CARE NOT TO DAMAGE THE COVER
PAINTED SURFACE.

Removing the driven pulley

- Lock the clutch bell housing with the specific tool.

- Remove the nut, the clutch bell housing and the
whole of the driven pulley assembly.

N.B.

THE UNIT CAN ALSO BE REMOVED WITH THE
DRIVE PULLEY MOUNTED.

Specific tooling

020565Y Flywheel lock calliper spanner

ENG - 3

Engine LX 4tempi

Inspecting the clutch drum

- Check that the clutch bell is not worn or damaged.

- Measure the inner diameter of the clutch bell.

Characteristic

Clutch bell diameter/standard value

Ø 107+0.2 +0 mm

Clutch bell diameter/max. value allowed after
use

Ø 107.5 mm

Eccentricity measured /max.

0.20 mm

Removing the clutch

- Equip the tool with long pins screwed into position
«A» from the outside, insert the entire driven pulley
in the tool and have the central screw make con­tact.

CAUTION

THE TOOL WILL BE DEFORMED IF THE CEN­TRAL SCREW IS TIGHTENED UP TOO FAR.

- Using a 34 mm socket wrench remove the clutch
locking nut.

- Loosen the central screw by undoing spring of
the driven pulley unit

- Separate the components.

Specific tooling

020444Y Tool for fitting/ removing the driven
pulley clutch

ENG - 4

LX 4tempi Engine

Inspecting the clutch

- Check the thickness of the clutch mass friction
material.

- The masses must not show traces of lubricants;
otherwise, check the driven pulley unit seals.

N.B.

UPON RUNNING-IN, THE MASSES MUST EX­HIBIT A CENTRAL CONTACT SURFACE AND
MUST NOT BE DIFFERENT FROM ONE AN­OTHER.
VARIOUS CONDITIONS CAN CAUSE THE
CLUTCH TO TEAR.

CAUTION

DO NOT OPEN THE MASSES USING TOOLS
TO PREVENT A VARIATION IN THE RETURN
SPRING LOAD.

Characteristic

Check minimum thickness

1 mm

Pin retaining collar

- Remove the collar with the aid of 2 screwdrivers.

- Remove the three guide pins and the mobile half
pulley.

ENG - 5

Engine LX 4tempi

Removing the driven half-pulley bearing

- Remove the roller bearing with the special ex­tractor inserted from the bottom of the fixed half­pulley.

CAUTION

POSITION THE HOLDING EDGE OF THE EX­TRACTION PLIERS BETWEEN THE END OF
THE BEARING AND THE BUILT IN SEALING
RING.

Specific tooling

001467Y029 Bell for bearings, O.D. 38 mm

- Remove the ball bearing retention snap ring.

- Expel the ball bearing from the side of the clutch
housing by means of the special tool.

N.B.

PROPERLY SUPPORT THE HALF-PULLEY SO
AS NOT TO DEFORM THE SLIDING SURFACE
OF THE DRIVING BELT

Specific tooling

020376Y Adaptor handle
020363Y 20 mm guide

Inspecting the driven fixed half-pulley

- Check that there are no signs of wear on the work
surface of the belt. If there are, replace the half­pulley..

- Make sure the bearings do not show signs of un­usual wear.

- Measure the external diameter of the pulley bush­ing.

Characteristic

Stationary driven half-pulley/Standard diame­ter

Ø 33.965 to 33.985 mm

Stationary driven half-pulley / Minimum diam­eter admitted after use

Ø 33.96 mm

ENG - 6

LX 4tempi Engine

Inspecting the driven sliding half-pulley

- Remove the 2 inner sealing rings and the two O­rings.

- Measure the inside diameter of the mobile half­pulley bushing.

Characteristic

Mobile driven half-pulley/ Maximum diameter
allowed

Ø 34.08 mm

- Check the belt contact surfaces.

- Insert the new oil seal and O-rings on the mobile
half-pulley.

- Fitting the half-pulley on the bushing.

Recommended products

AGIP GREASE SM 2 Grease for the tone wheel
revolving ring

Soap-based lithium grease containing NLGI 2 Mo­lybdenum disulphide; ISO-L-XBCHB2, DIN
KF2K-20

- Make sure the pins and collar are not worn, reassemble the pins and collar.

- Use a greaser with a curved spout to lubricate the driven pulley unit with around 6 gr. of grease. This
operation must be done through one of the holes inside the bushing until grease comes out of the
opposite hole. This procedure is necessary to prevent the presence of grease beyond the O-ring.

Recommended products

AGIP GREASE SM 2 Grease for the tone wheel revolving ring

Soap-based lithium grease containing NLGI 2 Molybdenum disulphide; ISO-L-XBCHB2, DIN KF2K-20

Refitting the driven half-pulley bearing

- Fit a new ball bearing with the specific tool.

- Fit the ball bearing retention snap ring.

- Fit the new roller bearing with the wording visible
from the outside.

CAUTION

PROPERLY SUPPORT THE HALF-PULLEY TO
PREVENT DAMAGE TO THE THREADED END
WHILE THE BEARINGS ARE BEING FITTED.

Specific tooling

020376Y Adaptor handle

ENG - 7

Engine LX 4tempi

020456Y Ø 24 mm adaptor
020362Y 12 mm guide
020171Y Punch for Ø 17 mm roller case

Inspecting the clutch spring

- Check that the contrast spring of the driven pulley
does not show signs of deformation

- Measure the free length of the spring

Characteristic

Standard length

118 mm

Minimum length allowed after use

XXXX

- Check the thickness of the clutch mass friction
material.

-The masses must not show traces of lubricants;
otherwise, check the driven pulley unit.

N.B.

UPON RUNNING-IN, THE MASSES MUST EX­HIBIT A CENTRAL CONTACT SURFACE AND
MUST NOT BE DIFFERENT FROM ONE AN­OTHER. VARIOUS CONDITIONS CAN CAUSE
THE CLUTCH TO TEAR.

CAUTION

DO NOT OPEN THE MASSES USING TOOLS
SO AS TO PREVENT A VARIATION IN THE RE­TURN SPRING LOAD.

Characteristic

Minimum thickness permitted:

1 mm

Refitting the clutch

- Preassemble the driven pulley group with spring,
sheath and clutch.

- Position the spring with the sheath

- Insert the components in the tool and preload the
spring being careful not to damage the plastic
sheath and the end of the threaded bar.

ENG - 8

LX 4tempi Engine

- Reassemble the nut securing the clutch and tight­en to the prescribed torque.

CAUTION

SO AS NOT TO DAMAGE THE CLUTCH NUT
USE A SOCKET WRENCH WITH SMALL
CHAMFER.

CAUTION

POSITION THE NON-CHAMFERED SURFACES
OF THE NUT IN CONTACT WITH THE CLUTCH

Locking torques (N*m)

Nut locking clutch unit on pulley 55 ÷ 60 Nm

Refitting the driven pulley

-Refit the driven pulley assembly, the clutch bell
and the nut, using the specific tool.

Specific tooling

020565Y Flywheel lock calliper spanner

Locking torques (N*m)

Driven pulley shaft nut 40 to 44 Nm

Drive-belt

- Make sure the driving belt is not damaged and
does not have cracks in the toothed grooves.

- Check the width of the belt.

Characteristic

Transmission belt/Minimum width

17.5 mm

ENG - 9

Engine LX 4tempi

Removing the driving pulley

- Lock the driving pulley using the appropriate tool.

- Remove the central nut with the related washer,
then remove the drive and the plastic fan.

- Remove the stationary half-pulley.

- Remove the belt, washer and remove the mobile half-pulley with its bushing, being careful that the
rollers and contrast plate fitted loosely on it do not come off.

Specific tooling

020451Y Start-up crown lock

Inspecting the rollers case

1) Check that the bushing and the sliding rings of
the mobile pulley do not show signs of scoring or
deformation.

2) Check the roller running tracks on the contact
pulley; there must not be signs of wear and check
the condition of the contact surface of the belt on
the half-pulleys (mobile and stationary).

3) Check that the rollers do not show signs of
marked facetting on the sliding surface and that
the metallic insert does not come out of the plastic
shell borders.

4) Check the integrity of the sliding blocks of the
contact plate.

- Check that the internal bushing shown in the fig­ure is not abnormally worn and measure inside
diameter «A».

- Measure outside diameter «B» of the pulley slid­ing bushing shown in the figure.

CAUTION

DO NOT LUBRICATE OR CLEAN THE BUSH­ING.

Characteristic

ENG - 10

LX 4tempi Engine

Driving pulley / Maximum diameter:

20.12 mm

Driving pulley/ Standard diameter:

20.021 mm

Driving pulley bushing/ Diameter maximum:

XXX mm

Driving pulley bushing/ Standard diameter:

20 -0.020/-0.041mm

Refitting the driving pulley

- Manually move the mobile driven half-pulley
away pulling it towards the clutch unit and insert
the belt repeating the direction of rotation of the
first fitting.

N.B.

IT IS GOOD PRACTICE ALWAYS TO FIT THE
BELT SO THE WORDING CAN BE READ, IN
THE CASE THAT THIS DOES NOT SHOW A
FITTING SIDE.

- Refit the particular components of the assembly
(roller container assembly with bushing, limiting
washer, stationery half-pulley, cooling fan belt with
drive, washer and nut).

- Tighten the lock nut to torque 20 Nm and then
perform a final 90° lock preventing the rotation of
the drive pulley with the specific tooling.

N.B.

REPLACE THE NUT WITH A NEW ONE AT EV­ERY REFIT

CAUTION

IT IS MOST IMPORTANT WHEN FITTING THE
DRIVING PULLEY UNIT THAT THE BELT IS
FREE INSIDE IN ORDER TO AVOID MAKING A
WRONG TIGHTENING WITH THE POSSIBLE
LATER DAMAGE OF THE CRANKSHAFT
KNURLING.

Specific tooling

020451Y Start-up crown lock

Locking torques (N*m)

Crankshaft pulley nut 18 to 20 + 90° N.m

ENG - 11

Engine LX 4tempi

Refitting the transmission cover

- Check the following for wear: toothed section,
toothed section shaft, cover seat bushing, pinion
shaft and it seating in the crankcase and the return
spring.

- Remove the damaged components.

- Grease the spring.

- Remove the toothed sector and load the spring
with an appropriate tool.

- Refit the washer, the seeger and the Kick-start
lever.

Recommended products

AGIP GREASE MU3 Grease for odometer
transmission gear case

Soap-based lithium grease with NLGI 3; ISO-L­XBCHA3, DIN K3K-20

- Insert the pinion in its seating by pushing the starter lever.

- Fit the intake throat and tighten the 3 screws.

-Make sure the oil sump presents centring dowels
and sealing gaskets.

- Replace the cover tightening the 12 screws to the
prescribed torque.

-Refit the oil filling cap.

Locking torques (N*m)

Transmission cover screws 11 ÷ 13 Nm

End gear

ENG - 12

LX 4tempi Engine

Removing the hub cover

• Remove the transmission cover

• Remove the clutch assembly

• Discharge the rear hub oil.

• Remove the 5 screws indicated in the figure.

• Remove the hub cover with driven pulley shaft.

See also

Refitting the clutch

Removing the wheel axle

- Remove the intermediate gear and the complete
gear wheel axle.

- When removing the intermediate gear pay atten­tion to the various shim adjustments.

Removing the wheel axle bearings

- Remove the oil seal and the seeger ring.

- Remove the bearing by pushing from the outside
towards the inside of the gear compartment, using
the appropriate punch.

Specific tooling

020363Y 20 mm guide
020376Y Adaptor handle
020358Y 37x40-mm adaptor

ENG - 13

Engine LX 4tempi

Removing the driven pulley shaft bearing

- Remove the seeger ring inside the cover.

- Remove the oil seal from the outside.

- Remove the centring dowels and position the
cover on a plane.

- Position the special tool on the internal track of
the bearing and remove said bearing with the aid
of a press.

Specific tooling

020452Y Tube for removing and refitting the
driven pulley shaft

- Position the special tube on the internal raceway
of the bearing and from the shaft toothed side as
indicated in the figure. Expel the driven pulley shaft
with the aid of a press.

Specific tooling

020452Y Tube for removing and refitting the
driven pulley shaft

Inspecting the hub shaft

- Check the three shafts for wear or distortion of
the toothed surfaces, the bearing housings, and
the oil seal housings.

- In case of anomalies, replace the damaged com­ponents.

- Check capacity ( A ) of the transmission gear
(wear, deformations, etc.)

- Check the pulley shaft seating: Superficial wear
( B ) may indicate irregularities in the crankcase
seatings or in the pulley shaft capacities

Inspecting the hub cover

- Check that the fitting surface is not dented or distorted.

- If faults are found, replace the hub cover.

ENG - 14

LX 4tempi Engine

Refitting the driven pulley shaft bearing

- Support the inner track of the bearing from the
outside of the hub cover with the specific tool posi­tioned under the press and insert the driven pulley
axle.

- Refit the oil seal flush with the cover.

Specific tooling

020452Y Tube for removing and refitting the
driven pulley shaft

• Heat the hub cover and insert the bearing with
the specific punch.

• Fit the snap ring with the concave or radial part
on the bearing side.

N.B.

FIT THE BALL BEARING WITH THE SHIELD
FACING THE OIL SEAL.

Specific tooling

020151Y Air heater
020376Y Adaptor handle
020439Y 17 mm guide
020358Y 37x40-mm adaptor

Refitting the wheel axle bearing

- Heat the half crankcase on the transmission side
using a thermal gun.

- After lubricating its outer strip, insert the bearing
with the special adapter with the aid of a hammer.

- Refit the seeger ring and the oil seal using the 42
x 47 mm adapter and the handle.

Specific tooling

020151Y Air heater
020376Y Adaptor handle
020363Y 20 mm guide
020359Y 42x47-mm adaptor

ENG - 15

Engine LX 4tempi

Refitting the ub cover

- Refit the whole wheel axle.

- Refit the intermediate gear paying attention to the
two shim thicknesses.

- Apply LOCTITE 510 for surfaces to the hub cov­ers and refit the same with driven pulley shaft.

- Refit the 5 screws and tighten them to the speci­fied torque.

N.B.

CLEAN THE CONTACT SURFACES OF THE
HUB COVER AND THE HALF CRANKCASE OF
RESIDUE FROM PREVIOUS GASKETS BE­FORE APPLYING A NEW ONE.

Locking torques (N*m)

Locking torque: 11 to 13 Nm

Flywheel cover

Cooling hood

- Remove the manifold and the carburettor undo­ing the 2 fixing screws on the head

- Remove the fastening clamp of the secondary air
pipe and disconnect it

- Remove the 4 front coupling screws (1 of them is
a knob) and the side fixing screw at the crankcase
base.

- Remove the 4 side screws

- Extract the 3 covers - Remove the cover sealing
gaskets on the head

- For refitting, repeat the removal steps but in re­verse order

CAUTION

TAKE CARE TO CORRECTLY POSITION THE
FLYWHEEL CONNECTOR.

N.B.

ENG - 16

LX 4tempi Engine

WHEN REFITTING THE COVER, TAKE CARE
NOT TO DAMAGE THE STATOR WIRING.

Cooling fan

- Remove the cooling fan by undoing the 3 screws
fixing it to the rotor

- When refitting the fan, pay attention that the
screw holes in the fan and the rotor coincide, then
tighten screws at the specified torque.

Removing the stator

- Remove the 2 Pick-Up screws and the 2 stator
fixing screws indicated in the figure.

- Remove the stator and its wiring.

ENG - 17

Engine LX 4tempi

Refitting the stator

- Refit the stator and flywheel carrying out the re­moval procedure in reverse, tightening the retain­ers to the specified torque.

N.B.

THE PICK-UP CABLE MUST BE POSITIONED
ADHERING TO THE FUSION TONGUE ON THE
CRANKSHAFT IN SUCH A WAY AS TO AVOID
BEING CRUSHED BY THE FAN COVER AS­SEMBLY.

Locking torques (N*m)

Pick-up screws 3 ÷ 4 Stator screws 3 ÷ 4

Flywheel and starting

Removing the starter motor

- Unscrew the screw on the power positive contact
and disconnect the cable

- Unscrew the 2 screws fixing the starter motor to
the crankcase and recover the power wiring.

ENG - 18

LX 4tempi Engine

Removing the flywheel magneto

- Lock the rotation of the flywheel using the calliper
spanner.

- Remove the nut.

CAUTION

THE USE OF A CALLIPER SPANNER OTHER
THAN THE ONE SUPPLIED COULD DAMAGE
THE STATOR COILS

- Extract the flywheel with the extractor.

Specific tooling

020565Y Flywheel lock calliper spanner
020162Y Flywheel extractor

Inspecting the flywheel components

- Check that the flywheel internal magnets are in
good conditions.

- Check that the flywheel riveted joints are correctly
tightened.

- Check there are no deformations that may cause
rubbing on the stator and the Pick-Up.

- Check that the stator winding, its ferromagnetic
support and the pick-up are in good conditions.

ENG - 19

Engine LX 4tempi

Starter gear rim

- Check the toothing is level and in good conditions

Intermediate gear

- Check that the keying toothing on the crown and
the starter motor are in good conditions.

- Check that the bendix opens and returns ade­quately.

Refitting the flywheel magneto

- Refit the stator and the pick-up being careful to
pass the wiring through the appropriate crankcase
couplings.

- Refit the flywheel to the crankshaft being careful
to respect the keying, then lock rotation with the
specific tool and tighten the nut to the prescribed
torque.

N.B.

A VARIATION OF THE AIR GAP DISTANCE
CAN LEAD TO A VARIATION IN THE IGNITION
ADVANCE SUCH AS TO CAUSE PINGING,
KNOCKING ETC.

Specific tooling

020565Y Flywheel lock calliper spanner

Locking torques (N*m)

Flywheel nut 52 ÷ 58

ENG - 20

LX 4tempi Engine

Refitting the starter motor

- Install the starter motor in its seating in the crank­case.

- Tighten the screw on the head side but do not
lock it, screw the second screw inserting the earth
cable (black), then tighten the 2 screws at the pre­scribed torque.

- Tighten the locking screw of the positive cable
(red) on the side contact.

N.B.

REFIT THE REMAINING PARTS AS DESCRI­BED IN THE CYLINDER HEAD, TIMING, LUBRI­CATION, FLYWHEEL AND TRANSMISSION
CHAPTERS.

Locking torques (N*m)

Starter motor screws 11 ÷ 13

Cylinder assy. and timing system

Removing the rocker-arms cover

- Remove the cooling covers

- Remove the 4 retainers of the tappet cover

- Remove the cover and the O-ring

- Remove the 4 screws and then remove the Blow­by cover

- Clean the nozzle labyrinth and the membrane
(replace it, if necessary), then remove the cover
unit.

ENG - 21

Engine LX 4tempi

Removing the timing system drive

- Temporarily loosen the tensioner central screw
and remove it together with the spring.

- Unscrew the 2 retainers indicated in the figure
and remove the chain tightener support being
careful to recover the sealing gasket.

N.B.

SHOULD THE GASKET NOT BE IN GOOD CON­DITIONS, REPLACE IT AFTER CAREFULLY
CLEANING THE FAYING SURFACE IN ORDER
TO AVOID ENGINE OIL LEAKS

- Remove the driving pulley

- Remove the oil pump chain

- Remove the tappet cover

- Remove the central screw and the belleville
washer indicated in the figure and lock the cam­shaft crown with the specific tool.

N.B.

TO FACILITATE REMOVING THE HEAD COM­PONENTS, SET THE CRANKSHAFT TO THE
TIMING POINT (TDC OF THE COMPRESSION
END).

Specific tooling

020565Y Flywheel lock calliper spanner

- Remove the camshaft control pulley and the washer below.

- Remove the pinion of the crankshaft timing control

- To remove the chain lower guiding pad, remove the head by pulling it upwards

N.B.

IT IS ADVISABLE TO MARK THE CHAIN IN ORDER TO ENSURE THAT THE DIRECTION OF RO­TATION IS MAINTAINED.

See also

Removing the rocker-arms cover

ENG - 22

LX 4tempi Engine

Removal
Removing the driving pulley

Removing the cam shaft

- Remove the bearing clamping screw indicated in
the figure.

- Remove the entire camshaft with bearing using
the specific tool shown in the figure.

- Take out the camshaft bearing with the aid of the
specific tool, being careful to mount a screw on the
camshaft in order to protect its thread.

N.B.

IF A BEARING SEPARATES FROM THE CAM­SHAFT, IT IS ESSENTIAL TO FIT A NEW BEAR.

Specific tooling

020450Y Camshaft fitting/removal tool
004499Y Camshaft bearing extractor
004499Y001 Bearing extractor bell
004499Y002 Bearing extractor screw
004499Y006 Bearing extractor ring
004499Y027 Bearing extractor part

- Pull out the rocking lever bolt operating on the
flywheel hole and remove the rocking levers at the
same time.

N.B.

MARK THE ASSEMBLY POSITION OF THE
ROCKING LEVERS IN ORDER TO AVOID MIS­PLACING THE INTAKE AND DISCHARGE
ENDS.

ENG - 23

Engine LX 4tempi

Removing the cylinder head

- Remove the cooling covers, the timing control,
the camshaft and the rocking levers.

- Remove the spark plug.

- Remove the 2 side fixings shown in the figure.

- Loosen the 4 head-cylinder fastening nuts in two
or three stages and in criss-cross fashion.

- Remove the head, the two centring dowels and
the gasket.

N.B.

IF NEEDED, THE HEAD MAY BE REMOVED
WITH THE CAMSHAFT, PINS AND ROCKING
LEVERS WITHOUT REMOVING THE DRIVING
PULLEY UNIT. REMEMBER TO HOLD THE TIM­ING CHAIN WITH A PIECE OF METAL CABLE
AND TO ADJUST THE CHAIN TIGHTENER
UPON REFITTING.

Removing the valves

- Using the specific tool fitted with the element
shown in the figure, remove the cotters, the plates
and the spring between the valves.

- Remove the oil seals with the appropriate tool.

- Remove the lower spring supports.

Specific tooling

020431Y Valve oil seal extractor

ENG - 24

LX 4tempi Engine

Removing the cylinder - piston assy.

- Remove the cylinder paying attention to the 2
cylinder centring dowels in the housing.

- Remove the cylinder base gasket.
To avoid damaging the piston, keep it fixed while
removing the cylinder.

- Remove the two stop rings, the wrist pin and the
piston.

- Remove the 3 piston rings.

N.B.

BE CAREFUL NOT TO DAMAGE THE PISTON
RINGS DURING REMOVAL.

Inspecting the small end

- Measure the internal diameter of the small end
using an internal micrometer.

N.B.

IF THE DIAMETER OF THE ROD SMALL END
EXCEEDS THE MAXIMUM DIAMETER AL­LOWED, SHOWS SIGNS OF WEAR OR OVER­HEATING REPLACE THE CRANKSHAFT AS
DESCRIBED IN THE "CRANKCASE AND
CRANKSHAFT" CHAPTER".

Characteristic

Max. diameter admitted: check the small end

13.030 mm

Standard diameter check the small end

13 +0.025+0.015mm

ENG - 25

Engine LX 4tempi

Inspecting the wrist pin

- Measure the outer diameter of the gudgeon pin.

Characteristic

Standard diameter gudgeon pin

13 -0-0.004mm

Minimum admissible diameter pin

12.990 mm

Inspecting the piston

- Carefully clean the sealing rings housings with the aid of an old piston ring.

- Measure the coupling clearance between the sealing rings and the piston grooves using a thickness
gauge, as shown in the figure.

- If the clearances detected exceed the limits specified in the table, the piston and the piston rings should
be replaced.

PISTON

Name Description Dimensions Initials Quantity

Top piston ring 0.030 ÷ 0.065 mm 0.080 mm

Middle piston ring 0.020 ÷ 0.055 mm 0.070 mm

oil scraper 0.040 ÷ 0.160 mm 0.20 mm

- Calculate the piston pin coupling clearance.

Fitting clearance

Pin coupling clearance 13 +0.010+0.005mm

0.005 ÷ 0.014 mm

ENG - 26

LX 4tempi Engine

- Measure the outside diameter of the piston, perpendicular to the gudgeon pin axis.

- Carry out the measurement at 27 from the piston crown as shown in the figure.

Inspecting the cylinder

- Using a bore meter, measure the inner cylinder
diameter at three different points according to the
directions shown in the figure.

- Check that the coupling surface with the head is
not worn or misshapen.

- Pistons and cylinders are classified into catego­ries based on their diameter. The coupling is car­ried out in pairs (A-A, B-B, C-C, D-D).

Characteristic

Maximum allowable run-out:

0.05 mm

- The cylinder rectifying operation should be car­ried out with a surfacing that respects the original
angle. at 120° crossed.

- The cylinder surface roughness should be of
R.A.= 0.30 ÷ 0.50.

- This is indispensable for a good seating of the
sealing rings, which in turn minimises oil consump­tion and guarantees optimum performance.

- The pistons are oversized due to cylinder rectifi­cation and are subdivided into two categories 1st
and 2nd with 0.2-0.4mm oversize. They are also
classified into 4 categories A-A, B-B, C-C, D-D.

Inspecting the piston rings

- Alternately insert the three sealing rings into the cylinder, in the area where it retains its original di­ameter. Using the piston, insert the rings perpendicularly to the cylinder axis.

- Measure the opening, see figure, of the sealing rings using a thickness gauge.

- If any measurements are greater than specified, replace the piston rings.

N.B.

BEFORE REPLACING ONLY THE PISTON RINGS, ENSURE THAT THE CLEARANCE BETWEEN
THE PISTON RINGS AND THE PISTON RING GROOVES, AND BETWEEN THE PISTON AND THE
CYLINDER, IS AS SPECIFIED. IN ANY CASE, NEW PISTON RINGS USED IN COMBINATION WITH
A USED CYLINDER MAY HAVE DIFFERENT BEDDING CONDITIONS THAN THE STANDARD.

ENG - 27

Engine LX 4tempi

SEALING RINGS

Name Description Dimensions Initials Quantity

Top piston ring 0.08 ÷ 0.20 mm 0.35 mm

Middle piston ring 0.05 ÷ 0.20 mm 0.30 mm

oil scraper 0.20 ÷ 0.70 mm 0.80 mm

Removing the piston

- Install piston and wrist pin onto the connecting
rod, aligning the piston arrow the arrow facing to­wards the exhaust.

- Fit the pin stop ring onto the appropriate tool.

Specific tooling

020448Y Pin lock fitting tool

- With the opening in the position indicated on the
tool, set the lock ring into position in the tool with
the punch.

- Rest the tool on the piston paying attention that
the 90°chamfered side faces upwards as indicated
in the figure.

- Fit the gudgeon pin stop using the plug.

CAUTION

USING A HAMMER TO POSITION THE RINGS
CAN DAMAGE THE LOCKING HOUSING.

ENG - 28

LX 4tempi Engine

Refitting the piston rings

- Alternately insert the three sealing rings into the
cylinder, in the area where it retains its original di­ameter. Using the piston, insert the rings perpen­dicularly to the cylinder axis.

- Measure the opening, see figure, of the sealing
rings using a thickness gauge.

- If any measurements are greater than specified,
replace the piston rings.

N.B.

BEFORE REPLACING ONLY THE PISTON
RINGS, ENSURE THAT THE CLEARANCE BE­TWEEN THE PISTON RINGS AND THE PISTON
RING GROOVES, AND BETWEEN THE PISTON
AND THE CYLINDER, IS AS SPECIFIED. IN ANY
CASE, NEW PISTON RINGS USED IN COMBI­NATION WITH A USED CYLINDER MAY HAVE
DIFFERENT BEDDING CONDITIONS THAN
THE STANDARD.

SEALING RINGS

Name Descrip

tion

Top pis-

ton ring

Middle

piston

ring

oil scra-

per

Dimens

ions

0.08 ÷

0.20 mm

0.05 ÷

0.20 mm

0.20 ÷

0.70 mm

Initials Quantit

y

0.35 mm

0.30 mm

0.80 mm

ENG - 29

Engine LX 4tempi

- Fit the oil scraper ring starting from the spring,
taking care that the spring ends do not superim­pose. Fit the two piston rings so that their gaps and
that of the oil scraper ring are never aligned.

- Fit the 2nd sealing ring with the identifying letter
«T» facing towards the piston crown.

- Fit the 1st sealing ring with the reference letter
«T» facing towards the piston crown.

- Offset the ring gaps by 120° to each other as
shown in the figure.

- Lubricate the components with engine oil.

N.B.

IN ORDER TO OBTAIN A GOOD BEDDING, THE
2 SEALING PISTON RINGS ARE MADE OF
CONE SHAPED CONTACT SECTION TO THE
CYLINDER. AS A RESULT IT IS IMPORTANT
TO RESPECT THE FITTING INSTRUCTION TO
ASSEMBLY THE RINGS WITH THE "T" MARK
FACING UPWARDS.

Refitting the cylinder

- Insert the cylinder base gasket.

- Fit the cylinder as shown in the figure.

- It is possible to maintain the piston out of the
crankcase plane using the special tool.

N.B.

BEFORE FITTING THE CYLINDER, CAREFUL­LY BLOW OUT THE LUBRICATION DUCT AND
OIL THE CYLINDER BARREL.

Specific tooling

020288Y Fork to assemble piston on cylinder

When replacing the four cylinder studs, on this engine, the head nuts must be tightened according to
the procedure below.
This differs from what is specified on the vehicle's manual:

ENG - 30