Piaggio Vespa WORKSHOP Derbi BOULEVARD 125 150 200 Workshop Manual

WORKSHOP MANUAL

BOULEVARD 125/150/200 c.c.

1

This manual has been prepared by Nacional Motor, S.A.U. for use in the
workshops of Derbi distributors and sub-agencies. It is assumed that all
those who use this manual for the maintenance and repair of Derbi vehi­cles should have a knowledge of the basic principles of the mechanics
and methods required for the repair of such vehicles. Major variations in
the technical specifications of the vehicles or in specific repair operations
shall be communicated to workshops by means of updates to this
manual.
Nevertheless, completely satisfactory work cannot be performed where
the necessary facilities and tools are not available: we therefore request
that you consult those pages of this manual which discuss these specific
tools and the catalogue of specific tools and equipment.
The most important information in this manual is highlighted by the
following notices:

N.B.: This indicates a note giving key information which helps to make a
procedure easier and more straightforward.

- This indicates specific procedures which must be followed to

avoid causing damage to the vehicle.

- This indicates specific procedures which must be follo-

wed to avoid any mishap to the mechanic working on the vehicle.

Caution

Warning

 DERBI - NACIONAL MOTOR Sociedad Unipersonal / 2002 • N.º 7077TG02002

Workshop Manual

GENERAL NORMS

2

Safety Rules

- In those cases where it is necessary to have
the engine running in order to carry out work
on the vehicle, care should be taken to
ensure that the area is well-ventilated, and if
necessary use appropriate fans; never start
the engine in a closed space. Exhaust gases
are poisonous.

- Battery electrolyte contains sulphuric acid.
The eyes, clothing and the skin should be
protected. Sulphuric acid is highly corrosive;
if it enters into contact with the eyes or the
skin, wash with copious amounts of water
and seek medical advice immediately.

- The battery produces hydrogen, a gas which
in certain circumstances may be highly
explosive. Do not smoke or permit open fla­mes or sparks in the vicinity of the battery, in
particular while the battery is being charged.

- Petrol fuel is highly inflammable, and under
certain circumstances may be explosive. No
smoking should be allowed in the working
area, and open flames or sparks should be
avoided.

- Brake pads and brake shoes should be clea­ned in a well-ventilated area, aiming the jet
of compressed air used for cleaning in such
a way that the dust produced from brake
wear cannot be inhaled. The brake pads and
brake shoes do not contain asbestos;
nevertheless inhaling the dust is dangerous
to the health.

Maintenance rules

- Use original DERBI spare parts and the
lubricants recommended by the manufactu­rer. Non-original and non-compliant spare
parts may damage the vehicle.

- Use only the specific tools designed for this
vehicle.

- Always use new gaskets, oil seals, and clips
when reassembling the machine.

- After stripping the machine, clean all compo­nents with a non-inflammable solvent, or one
with a high ignition point. Lubricate all wor­king surfaces before re-assembly, except for
conical fittings.

- After rebuilding the machine, check that all
the components have been correctly insta­lled, and that they work properly.

- During the stripping, servicing, and re­assembly operations, use metric tools exclu­sively. Metric screws and nuts are NOT inter­changeable with those using English measu­rements. Using inappropriate tools and secu­ring elements may cause damage to the
machine.

- In those cases where work on the machine
involves the electrical circuits, check that the
electrical connections are correctly re-con­nected, in particular earthing connections
and battery connections.

TABLE OF CONTENTS

TECHNICAL SPECIFICATIONS OF THE ENGINE.........................................4

INDISPENSABLE TOOLS................................................................................5

RECOMMENDED TOOLS ...............................................................................5

TROUBLESHOOTING................................................................................6 - 8

MAINTENANCE PROGRAMME ......................................................................9

TORQUE SETTINGS TABLE.........................................................................10

ELECTRICAL SYSTEM AND WIRING DIAGRAMS...............................11 - 24

SUSPENSIONS..............................................................................................25

CARBURETTOR.....................................................................................26 - 39

EVAPORATIVE EMISSION SYSTEM............................................................40

BRAKE SYSTEM............................................................................................41

PRIOR TO DELIVERY ...................................................................................42

ENGINE

GENERAL INFORMATION AND MAINTENANCE.................................43 - 49

TRANSMISSION.....................................................................................50 - 61

MAGNETO..............................................................................................61 - 64

LUBRICATION........................................................................................64 - 69

CYLINDER – CYLINDER HEAD – DISTRIBUTOR.................................70 - 89

CRANKCASE – CRANKSHAFT..............................................................90 - 97

STARTER MOTOR ........................................................................................97

3

TECHNICAL SPECIFICATIONS OF THE ENGINE

1. DIMENSIONS 125 C.C. 150 C.C. 200 C.C.

OVERALL LENGTH mm
OVERALL HEIGHT mm
WHEELBASE mm
OVERALL WIDTH AT HANDLEBARS mm
OVERALL HEIGHT AT HANDLEBARS mm
USEFUL LENGTH SADDLE mm
HEIGHT OF FOOTBOARD OR FOOTREST mm
USEFUL HEIGHT OF SADDLE mm
USEFUL LENGTH OF FOOTREST mm
MINIMUM GROUND CLEARANCE mm
OVERALL WIDTH FRONT mm
OVERALL WIDTH REAR mm
CLEARANCE INNER SHIELD TO SADDLE mm
STEERING ANGLE
FORKS TRIANGLE (LEADING ANGLE x E/C BARS) *
WHEEL AXLE LEADING -TRAILING mm
STEERING TRAIL mm
SHOCK ABSORBER MOUNTING ANGLE
ENGINE-GROUND MOUNTING ANGLE

2. TYRES. BRAKES. SUSPENSION

FRONT TYRE (TYPE)
FRONT TYRE (PRES.-SINGLE RIDER/RIDER & PILLION)
REAR TYRE (TYPE)
REAR TYRE (PRES.-SINGLE RIDER/RIDER & PILLION)
FRONT BRAKE (DRUM or DISC - DIAMETER)
REAR BRAKE (DRUM or DISC - DIAMETER)
FRONT FORKS (NORMAL - INVERTED)
FRONT FORKS (MECHANICAL - HYDRAULIC)
FRONT FORK BARS - DIAMETER mm
FRONT WHEEL AND SUSPENSION STROKE mm
SHOCK ABSORBER PIN DIAMETER mm
REAR WHEEL AND SUSPENSION STROKE mm

3. TECHNICAL PARAMETERS OF THE ENGINE

BASIC ENGINE (TYPE)
BORE x STROKE
CUBIC CAPACITY
MAXIMUM POWER
MAXIMUM TORQUE
COOLING
VARIABLE SPEED DRIVE TRANSMISSION RATIO
CLUTCH
TRANSMISSION REDUCTION GEAR RATIO
POWER/WEIGHT RATIO

4. VEHICLE PERFORMANCE FIGURES

MAX. SPEED

5. CAPACITY PARAMETERS

PETROL TANK WITH RESERVE
HELMET BOX CAPACITY (HELMET TYPE)
TOP CASE (YES - NO)
TOTAL VEHICLE KERB WEIGHT

6. ELECTRICAL PARAMETERS

STAND. BATTERY, requiring/not requiring mainten.
MAGNETO 12V 160w =
MAX SPEED ON SPEEDOMETER
HEADLAMP BULB (W) 1
PARKING LIGHT (W)
STANDARD TAIL LIGHT
TAIL / STOP LIGHT BULB (W)
REGISTRATION PLATE LIGHT
INDICATOR LIGHT BULBS (W)

DRUM Diam. 140 mm

9,35 Nw-m at6500 R.P.M

FORCED AIR-COOLED

12V 9A, requiring maint.

2V 35/35 w HS1 Halogen

FAIRED INTO BODYWORK

1860
116 5
1305

690

1060
650-700
350/400

805
350
170
470
580
300

24,5º

10mm/206mm

Leading 17 mm

89

22.5

13,8º

130/60x13”

1,4/1,6

130/60x13”

1,6/1,18

DISC Diam. 220 mm

CONVENTIONAL

HYDRAULIC

35mm

75/75mm

10mm
75mm

125cc 4-stroke 2-valve

57 x 48,6 mm

124,015cm

7,61 Kw at 7500 R.P.M

1:2,7/1:0,809=3,34

DRY, CENTRIFUGAL

< 0,11 Kw/Kg

98 Km/h

FULL-FACE MAX.

Yes, 35L

123 Kg

12V 160w

140Km/h

12V 5w

12V 21/5w

12V 5w

12V 10w

³

9.97

9L

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150cc 4-stroke 2-valve

62,6 x 48,6 mm

149,58 cm³

8,13 KW at 7000 R.P.M

11,54 Nw-m at 6000 R.P.M

FORCED AIR-COOLED

1:2,7/1:0,809=3,34

DRY, CENTRIFUGAL

9.2

< 0,11 Kw/Kg

102 Km/h

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127 Kg

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200 4-stroke 2-valve

72 x 48,6 mm

198 cm³

12,5 CV at 6750 R.P.M

17,2 N.m at 5250 R.P.M

FORCED AIR-COOLED

2,7:1 / 0,809:1

DRY, CENTRIFUGAL

9.2:1

< 0,11 Kw/Kg

102 Km/h

=
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=

124 Kg

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4

SPECIFIC TOOLS

5

Indispensable Tools

Name Drawing Number

Hub 001467Y Part.9
Pliers, 15 mm 001467Y013
Magneto extractor tool 008564Y
Oil pressure manometer gauge 020193Y
Half-pulley assembly sleeve 020263Y
Piston assembly skirt (125 cc engine) 020287Y
Valve sealing ring assembly punch 020306Y
Adapter 32 x 35 mm Driven Pulley shaft bearing assembly 020357Y
Adapter 42 x 47 mm hub bearing assembly 020359Y
Adapter 52 x 55 mm hub bearing assembly 020360Y
Guide 20 mm hub bearing assembly 020363Y
Guide 25 mm driven pulley ball-bearing assembly 020364Y
Driving pulley immobilising spanner (125 cc Engine) 020368Y
Adapter 28 x 30 mm driven pulley ball-bearing assembly 020375Y
Sleeve for adapters 020376Y
Boss (tool for stripping valves) 020382Y011
Piston assembly skirt (180 cc engine) 020393Y
Guide 15 mm hub bearing assembly 020412Y
Guide 28 mm hub bearing assembly 020414Y
Clutch hub immobilising spanner 020423Y
Driven pulley roller-cage assembly punch 020424Y
Magneto-side oil seal punch 020425Y
Support for projecting part of piston 020426Y
Piston assembly fork 020428Y
Pin clips assembly tool (125 cc engine) 020430Y
Valve oil seal extractor tool 020431Y
Oil pressure manometer gauge connector 020434Y
Guide 17 mm shock absorber bracket bearing assembly 020439Y
Water pump service tool 020440Y
Drive pulley immobilising spanner 020442Y
Driven semi-pulley spring compressor tool 020444Y
Pin clips assembly tool (180 cc engine) 020454Y
Guide 10 mm belt roller bearing assembly 020455Y
Magneto securing compass spanner 020565Y

Recommended Tools

Name Drawing Number

Support: to be fitted with the following parts:
15-Tube, 22-Cross-bar, 23-Nut, 44-Plate, 46-Vice 002095Y
Pliers for snap rings 002465Y
Crankshaft alignment tool 020074Y
Air-heater support for “METABO HG 1500/2” 020150Y
Air-heater for “METABO HG 1500/2” 020151Y
Crankcase separation plate 020262Y
Immobiliser control tester 020319Y
Vacuum pump, Mitivac type 020329Y
Strobe gun for 2-stroke and 4-stroke engines 020330Y
Digital multimeter 020331Y
Digital tachometer counter 020332Y
Individual battery charger 020333Y
Multiple battery charger 020334Y
Magnetic support and comparator 020335Y
Adapter for multimeter (measurement of peak voltages) 020409Y
Exhaust gas analyser 494929

POSSIBLE CAUSE

Dirty carburettor; injection pump or
one-way valve faulty

Excessive deposits in combustion
chamber

Incorrect timing adjustment, or worn
distributor elements

Blocked exhaust pipe silencer
Blocked or dirty air filter

Slipping clutch

Ineffective automatic transmission

Worn belt
Poor compression; wear in piston

rings, cylinder or valves
Oil level higher than maximum mark

Dirty carburettor; injector pump or
one-way valve faulty

Faulty spark-plug, or incorrect timing
advance

Blocked or dirty air filter

Ineffective choke

Engine drowned

Valves not seating correctly or inco­rrectly adjusted

Revolutions on starting too low or
engine and starter assembly faulty

Fuel characteristics altered

ACTION

Strip, wash with solvent, and dry
using compressed air, or replace

Decoke cylinder, piston, cylinder
head and the valves

Reset distributor timing, and replace
worn parts.

Replace
Try cleaning filter with air jet: failing

that, replace
Check and if necessary replace the

clutch assembly and clutch hub
Check rollers, and sliding action of

pulleys, replace faulty parts, and
lubricate the driven moving pulley
guide using grease (Montblanc
Molybdenum Grease)

Replace
Replace the worn parts

Check causes and ensure level is
correct

Strip, wash with solvent, and dry
using compressed air, or replace

Replace spark-plug or check ignition
circuit components

Try cleaning filter with air jet: failing
that, replace

Check; mechanical sliding action and
the device

Run starter with throttle fully open. If
the engine does not start, remove
and dry the spark-plug, and before
re-installing it turn the engine to force
out excess fuel, taking care to keep
the spark-plug cap connected to the
spark-plug, and the plug in contact
with ground. If the fuel tank has run
dry, start the engine only after re-fue­lling.

Service cylinder head and/or correct
valve play

Check starter motor, and installation

Empty tank of defective fuel and
refuel

TROUBLESHOOTING

6

SYMPTOM

Poor performance

Difficulty in starting

TROUBLESHOOTING

7

Wash the jet with solvent and dry using compressed air

SYMPTOM

Engine tends to stop at
full throttle

Engine tends to stop at
idle

Excessive fuel con­sumption

Juddering or uneven
clutch operation

POSSIBLE CAUSE

Dirty main jet – low carburation

Water in the carburettor

Incorrect float level
Faulty fuel supply circuit

Air-filter box does not seal properly
Idle jet dirty

Choke stays open

Faulty spark-plug or incorrect ignition
advance

Final compression pressure too low

Idle speed incorrectly adjusted

Cut-off device faulty

Incorrect distributor timing adjustment

Blocked or dirty air filter
Ineffective choke

Fuel pump faulty

Weak jets

Float level

Faulty clutch

ACTION

Wash the jet with solvent and dry
using compressed air

Empty the carburettor float chamber,
using the appropriate purge method

Restore correct float level
Check and if necessary replace the

pump and one-way valve, check the
vacuum intake and that the line is air­tight

Check and if necessary replace
Wash the jet with solvent and dry

using compressed air
Check: electrical connections, conti-

nuity of circuit, mechanical sliding
operation, and power supply

Replace spark-plug or check ignition
circuit components

Check seals on heating assembly,
and replace worn parts

Adjust using tachometer

Check effectiveness of valve; mem­brane, spring, and clean air vents;
check filter sponge clean

Reset distributor timing, and check
distribution elements

Clean with compressed air or replace
Check: electrical connections, conti-

nuity of circuit, mechanical sliding
operation, and power supply

Check that there is no fuel in the
vacuum line

Check for blockage in main and idle
jet seat

Check and reset correct fuel level in
carburettor

Check that there is no grease on the
weights

Check that the contact surface bet­ween the clutch weights and the hub
is preferably centred and appears the
same for all three weights

Check that the clutch hub is not sco­red or unusually worn

POSSIBLE CAUSE

Poor braking performance

Brake noise
This is the component in the entire installa-

tion which requires the most constant atten­tion, and the most careful maintenance

If the vehicle is left unused for more than a
certain period (1 month or more) it is neces­sary to recharge the battery periodically.
Over a period of about three months the
battery will tend to discharge completely.
When the battery has to be replaced in the
motorcycle, be careful not to invert the con­nections, and note that the black earth cable
must be connected to the negative terminal,
and the other cable, marked with a red
colour must be connected to the positive ter­minal marked with a “+” sign.

Steering becomes stiffer

Excessive steering play
Noisy suspension

Suspension losing oil

ACTION

Chech for worn pads
(Minimum 1,5 mm.)

Chech that the brake disc are not
worn, scored or mis-sharpen

Check for correct brake fluid level in
cylinders

Check for air in circuits, if necessary,
bleed

Check that the front brake caliper
moves axially with the disc

Check and, if necessary, change the
brake fluid

Check for worn brake pads

Check the tightness of the upper and
lower collars. If uneven turning is
noticed in the steering even after
adjusting the collars, check the ball
bearing seats; replace these if they
are jammed or if the balls appear flat­tened.

As above
If the front suspension is noisy,

check: effectiveness of front shock
absorber; the state of the ball bea­rings and their lock nuts; the rubber
stop plugs; the sliding bosses.

Finally check the torque settings of
the wheel bushing, the brake caliper,
the disc, and the shock absorber at
its securing points with the bush and
the steering tube.

Replace the shock absorber
Check the steering caps for wear and

adjustment.

TROUBLESHOOTING

8

SYMPTOM

Braking installation

Battery

Steering controls and
suspension

MAINTENANCE PROGRAMME

9

Check ■ Replace ● x 1000 Km 1 6 12 18 24 30 36 42 48 54 60 66 72

Months 4 12 24 36 - - - - - - - - -

Engine Oil Check level/fill up EVERY 3000 Km EVERY 3000 Km
Engine Oil Replace ●●●●●●●●●●●●

Hub Oil Level Check ●■■■●■■■●■■■●
Spark Plug/Spark Plug Gap Check/Replace ■●■●■●■●■●■●
Air Filter Check /Replace ■●■●■●■●■●■●
Oil Filter Replace ●●●●●●●●●●●●
Valve Play Check ■■ ■ ■
Check idle / Carburettor Adjust

■■■ ■ ■■ ■

Throttle control Adjust ■■■ ■ ■■ ■
Roller cage Check or Replace ■■■■■■■■■■■■
Transmission Belt Replace ■●■●■●■●■●■●
Speedometer Unit Grease ■■■ ■■■
Steering Adjust ■■■ ■ ■■ ■
Brake levers Grease ■■■■■■■
Brake Pads Check for wear EVERY 3000 Km EVERY 3000 Km
Brake flexible hoses Replace ●●
Brake Fluid Level Check ■■■■■■■■■■■■■
Brake Fluid Replace EVERY 2 YEARS EVERY 2 YEARS
Transmissions Lubrication ■■■■■■
Safety Locks Check ■■■ ■ ■■ ■
Suspensions Check ■■■ ■■■
Wiring harness and Battery Check

■■■■■■■■■■■■■

Headlight Beam Check / Adjust ■■■■■■
Tyre condition Check condition

and wear and wear ■■■■■■■■■■■■
Tyre pressures Check ■■■■■■■■■■■■■
Check vehicle

and brakes Road test ■■■■■■■■■■■■■
Labour time

60' 100' 135' 90' 160' 75' 185' 75' 160' 90' 135' 75' 210'

TORQUE SETTING TABLE

10

DESCRIPTION - PART Torque Setting in N-m

UPPER SHOCK ABSORBER SECURING ELEMENT - FRAME M8 x 100 8.8 20 ÷ 25
LOWER SHOCK ABSORBER SECURING ELEMENT - ENGINE M10 x 150 8.8 30 ÷ 40
ENGINE BRACKET SECURING ELEMENT - FRAME M10 X150 10.9 55 ÷ 60
ENGINE SECURING ELEMENT - ENGINE BRACKET M10 x 150 8.8 30 ÷ 40
ENGINE BRACKET SECURING ELEMENT - ENGINE BRACKET M10 x 150 8.8 30 ÷ 40
SILENTBLOC SECURING BRACKET - FRAME M8 x 125 8.8 15 ÷ 19 Sealed
FILTER BOX SECURING ELEMENT - ENGINE M6 x 100 8 ÷ 10
HORN SECURING ELEMENT - FRAME M6 x 100 8 ÷ 10
STEERING FORKS SECURING ELEMENT - FRAME M30.5 x 150 90 ÷ 130
EXHAUST PIPE TUBE SECURING ELEMENT - CYLINDER M6 X 100 9 ÷ 12
EXHAUST PIPE SECURING ELEMENT - CRANKCASE M8 x 125 15 ÷ 19 Sealed
HANDLEBAR SECURING ELEMENT - STEERING FORKS M10 x 150 8.8 30 ÷ 40
FRONT WHEEL SECURING ELEMENT - FORKS M12 x 175 8.8 45 ÷ 60
FORK LEG CLOSING SECURING ELEMENT - FORKS M6 x 100 8 ÷ 10
DISC BRAKE SECURING ELEMENT - FRONT WHEEL M6 x 10.9 11 ÷ 20 Sealed
FRONT BRAKE CALIPER SECURING ELEMENT - FORKS M8 x 125 8.8 17 ÷ 19 Sealed
REAR WHEEL SECURING ELEMENT - ENGINE M16 x 125 10.9 115 ÷ 125
CENTRAL STAND SECURING ELEMENT - CRANKCASE M10 x 150 8.8 30 ÷ 40
LUGGAGE RACK SECURING ELEMENT - FRAME M6 x 100 8.8 8 ÷ 10
FOOT REST BRACKET SECURING ELEMENT - FRAME M8 x 125 8.8 15 ÷ 19 Sealed

ENGINE ASSEMBLY

LUBRICATION

TRANSMISSION OIL DRAIN PLUG 24 ÷ 30
OIL FILTER 4 ÷ 6
OIL PUMP COVER SCREWS 0,7 ÷ 0,9
OIL PUMP SCREWS 5 ÷ 6
PUMP DRIVE PULLEY CHAIN SCREWS 10 ÷ 14
CHAIN COVER SCREWS 35 ÷ 45
OIL SUMP SCREWS 10 ÷ 14

CYLINDER HEAD - CYLINDER

SPARK PLUG 12 ÷ 14
CYLINDER HEAD COVER SCREWS 13 ÷ 13
CYLINDER HEAD – CYLINDER SECURING NUTS 28 ÷ 30
CYLINDER HEAD SIDE SECURING SCREWS 11 ÷ 13
DISTRIBUTOR ELEMENTS SCREWS 7 ÷ 8,5
CAMSHAFT SCREWS 7 ÷ 6
TENSIONER SHOE SCREWS 10 ÷ 14
HUB SCREW 11 ÷ 15
TENSIONER SCREW 11 ÷ 13
TENSIONER CENTRAL SCREW 5 ÷ 6

TRANSMISSION

BELT SUPPORT ROLLER SCREW 11 ÷ 13
CLUTCH ASSEMBLY NUT 55 ÷ 60
FIXED DRIVE SEMI-PULLEY NUT 75 ÷ 83
TRANSMISSION COVER SCREWS 11 ÷ 13
DRIVEN PULLEY SHAFT NUT 54 ÷ 60
BOSS COVER SCREWS 24 ÷ 27

MAGNETO

STATOR ASSEMBLY SCREWS 3 ÷ 4
MAGNETO NUT 52 ÷ 58

CRANKCASE AND CRANKSHAFT

INTERNAL ENGINE CRANKCASE PARTITION SCREW 4 ÷ 6
OIL FILTER CONNECTOR 28 ÷ 30
ENGINE CRANKCASE SCREWS 11 ÷ 13
PRE-FILTER COVER 24 ÷ 30
STARTER MOTOR SCREWS 11 ÷ 13

MISCELLANEOUS

VARIOUS METAL SECURING ELEMENTS TO FRAME 3,5 ÷ 4,5
VARIOUS METAL SECURING ELEMENTS TO FRAME 8 ÷ 10
VARIOUS METAL SECURING ELEMENTS TO FRAME 15 ÷ 1,9
VARIOUS PLASTIC SECURING ELEMENTS TO FRAME 1 ÷ 2
VARIOUS PLASTIC SECURING ELEMENTS TO FRAME 2 ÷ 35

LOCKTITE 243 TYPE THREAD SEAL

WIRING DIAGRAMS

11

1 PICK-UP 7 IMMOBILISER AERIAL
2 MAGNETO 8 FUSE, 7.5 A (A)
3 IGNITION SWITCH CONTACTS 9 VOLTAGE REGULATOR
4 ELECTRONICS UNIT 10 DIAGNOSTICS TESTER OUTPUT
5 SPARK PLUG 11 FUSE, 5A (A)
6 H.T. COIL

1 LIGHTS SWITCH 11 REGISTRATION PLATE LIGHT 12v 5w
2 MAGNETO 12 FUSE 5A
3 HEADLIGHTS PILOT LIGHT 12v 1.2w 13 IGNITION SWITCH CONTACTS
4 AUTOMATIC CHOKE 14 HEADLIGHT REMOTE CONTROL
5 VOLTAGE REGULATOR 15 ELECTRONICS UNIT
6 DIPPED BEAM HEADLIGHT BULB 12v 55w (H7) 16 HEADLIGHTS DIP SWITCH
7 5w FILAMENT IN TAIL LIGHT BULB 12v 5/21w 17 HEADLIGHTS (12v 55w (H3))
8 INSTRUMENT PANEL LIGHT BULB 12v 1.2w 4-OFF 18 FUSE, 10A
9 LIGHTS PILOT LIGHT 12v 1.2w 19 FUSE, 7.5A
10 DIPPED BEAM HEADLIGHT BULB 12v 5w

Lights and automatic choke section

WIRING DIAGRAMS

1 IGNITION SWITCH CONTACTS 8 FRONT STOP SWITCH AND STARTER CHECK
2 MAGNETO 9 REAR STOP SWITCH AND STARTER CHECK
3 FUSE, 7.5A 10 21w FILAMENT IN STOP LIGHT BULB 12v 5/21w
4 ELECTRIC START REMOTE CONTROL 11 STARTER PUSH BUTTON
5 VOLTAGE REGULATOR 12 STOP LIGHT REMOTE CONTROL
6 STARTER MOTOR 13 ADDITIONAL STOP PRE-INSTALLATION (14w)
7 BATTERY, 12V 12 Ah 14 FUSE, 10A

12

Battery charger and starter motor section

Pilot lights and level indicators

1 FUEL LEVEL SENSOR 7 VOLTAGE REGULATOR
2 FUEL RESERVE PILOT LIGHT 12v 1.2 w 8 OIL PRESSURE PILOT LIGHT 12v 2w
3 FUEL LEVEL INDICATOR 9 ENGINE OIL PRESSURE SENSOR
4 FUSE, 7.5 A
5 IGNITION SWITCH CONTACTS

6 MAGNETO

WIRING DIAGRAMS

13

Indicator lights and horn section

1 INDICATOR SWITCH 5 HORN PUSH-BUTTON
2 INDICATOR LIGHTS 12V 10w 4-OFF 6 FUSE, 7.5 AMPS
3 INDICATOR PILOT LIGHT BULBS 12v 2w 7 IGNITION SWITCH CONTACTS
4 HORN 8 ELECTRONICS UNIT

BOULEVARD 125 cc. WIRING DIAGRAM

14

1

HEADLIGHT ASSEMBLY 2 x 12V 35/35W - SIDE LIGHT 12V 5W

2 INSTRUMENT PANEL

2A

RIGHT TURN INDICATOR CONTROL PILOT LAMP 12V 2W
2B FULL BEAM CONTROL PILOT LAMP 12V 1,2W
2C INSTRUMENTS PANEL LIGHT 12V 1.2W
2D LIGHTS CONTROL PILOT LAMP 12V 1.2W
2E DIAGNOSTIC LED OUTPUT
2F FUEL WARNING CONTROL PILOT LAMP 12V 2W
2G

ENGINE OIL LOW PRESSURE PILOT LAMP 12V 2W

2H

LEFT TURN INDICATOR CONTROL PILOT LAMP 12V 2W
21 BATTERY VOLTMETER
2J FUEL LEVEL TRANSMITTER

3 KEYSWITCH
4 FRONT RIGHT TURN INDICATOR 12V 10W
5 FRONT LEFT TURN INDICATOR 12V 10W
6 REAR RIGHT TURN INDICATOR 12V 10W
7 REAR LEFT TURN INDICATOR 12V 10W
8

TAIL LIGHT TAIL - BRAKE LIGHT BULBS 12V 5W - 12V 10W
9 LIGHTS SELECTOR SWITCH
10 START BUTTON
11 LIGHTS SELECTOR - FULL BEAM FLASHER
12 TURN INDICATORS SELECTOR
13 HORN BUTTON
14 HORN

15 LIGHTS CONTACTOR
16 BRAKE LIGHT BUTTON
17 FUSE BOX

A FUSE 5A (DIAGNOSTIC LED)
B FUSE 5A (STOP-HORN-INSTRUMENT PANEL)
C FUSE 7,5A (FULL BEAM FLASHER)

D FUSE 5A (SIDE LIGHT)
18 CARBURETTOR HEATING ELEMENT
19 AUTOMATIC CHOKE
20 FLYWHEEL MAGNETO
21 PICK - UP
22 OIL PRESSURE SENSOR
23 ELECTRONIC IGNITION DEVICE
24 VOLTAGE REGULATOR
25 H.T. COIL
26 SPARK PLUG COVER
27 SPARK PLUG
28 STARTER MOTOR CONTACTOR
29 STARTER MOTOR
30 FUSE 15A (LIGHTS CONTACTOR)
31 FUSE 15A (GENERAL IGNITION)
32 12V 9Ah BATTERY
33 FUEL LEVEL SENSOR
34 IMMOBILIZER ANTENNA

Orange
Grün
Schwarz
Braun
WeiB
Grau
Gelb
Blau
Rot
Rosa
Violett

Orange
Vert
Noir
Marron
Blanc
Gris
Jaune
Blau
Rouge
Rosa
Violet

Orange
Green
Black
Brown
White
Gray
Yellow
Blue
Red
Pink
Violet

Arancio
Verde
Nero
Marrone
Bianco
Grigio
Giallo
Azzurro
Rosso
Rosa
Viola

Naranja
Verde
Negro
Marron
Blanco
Gris
Amarillo
Azul
Rojo
Rosa
Violeta

O

GR

B

BR

W
G

Y

BL

R

P

VI

DFUKIE

BOULEVARD 200cc. WIRING DIAGRAM (E)

1. HEADLIGHT ASSEMBLY 2 x 12V 35/35W - SIDE LIGHT 12V 5W

2. INSTRUMENT PANEL
2A. RIGHT TURN INDICAT. CONTROL PILOT LAMP 12V 2W
2B. FULL BEAM CONTROL PILOT LAMP 12V 1,2W
2C. INSTRUMENTS PANEL LIGHT 12V 1.2W
2D. LIGHTS CONTROL PILOT LAMP 12V 1.2W
2E. DIAGNOSTIC LED OUTPUT
2F. FUEL WARNING CONTROL PILOT LAMP 12V 2W
2G. ENGINE OIL LOW PRESSURE PILOT LAMP 12V 2W
2H. LEFT TURN INDICAT. CONTROL PILOT LAMP 12V 2W
2I. BATTERY VOLTMETER
2J. FUEL LEVEL TRANSMITTER

3. KEYSWITCH

4. FRONT RIGHT TURN INDICATOR 12V 10W

5. FRONT LEFT TURN INDICATOR 12V 10W

6. REAR RIGHT TURN INDICATOR 12V 10W

7. REAR LEFT TURN INDICATOR 12V 10W

8. TAIL LIGHT TAIL - BRAKE LIGHT BULBS 12V 5W - 12V 10W

9. LIGHTS SELECTOR SWITCH

10. START BUTTON

11. LIGHTS SELECTOR - FULL BEAM FLASHER

12. TURN INDICATORS SELECTOR

13. HORN BUTTON

14. HORN

15. LIGHTS CONTACTOR

16. BRAKE LIGHT BUTTON

17. FUSE BOX
A FUSE 5A (DIAGNOSTIC LED)
B FUSE 5A (STOP-HORN-INSTRUMENT PANEL)
C FUSE 7,5A (FULL BEAM FLASHER)
D FUSE 5A (SIDE LIGHT)

18. CARBURETTOR HEATING ELEMENT

19. AUTOMATIC CHOKE

20. FLYWHEEL MAGNETO

21. PICK - UP

22. OIL PRESSURE SENSOR

23. ELECTRONIC IGNITION DEVICE

24. VOLTAGE REGULATOR

25. H.T. COIL

26. SPARK PLUG COVER

27. SPARK PLUG

28. STARTER MOTOR CONTACTOR

29. STARTER MOTOR

30. FUSE 15A (LIGHTS CONTACTOR)

31. FUSE 15A (GENERAL IGNITION)

32. 12V 9Ah BATTERY

33. FUEL LEVEL SENSOR

34. IMMOBILIZER ANTENNA

DFUKI E

O

GR

B

BR

W

G
Y

BL

R
P

VI

Orange

Grün

Schwarz

Braun

WeiB
Grau

Gelb

Blau

Rot

Rosa

Violett

Orange

Vert

Noir

Marron

Blanc

Gris

Jaune

Blau

Rouge

Rosa
Violet

Orange

Green

Black

Brown

White

Gray

Yell ow

Blue

Red

Pink

Violet

Arancio

Marrone

Azzurro

Verde

Nero

Bianco

Grigio
Giallo

Rosso

Rosa
Viola

Naranja

Verde

Negro
Marron
Blanco

Gris

Amarillo

Azul

Rojo

Rosa

Violeta

15

INSTRUMENT PANEL WIRING DIAGRAM

16

“A” “B”

1. ILB Signal. 1. Left indicator light pilot light.

2. Immobiliser LED. 2. No connection.

3. Immobiliser LED. 3. + Battery via key lock.

4. Dipped beam headlight pilot light. 4. Engine oil pressure pilot light.

5. Earth. 5. Fuel reserve pilot light.

6. No connection.

7. Full beam headlight pilot light.

8. Right indicator light pilot light.

SISTEMA ELECTRICO

Electronic start (immobiliser
installation)

The electronic start is installed with a
DC power supply and includes an anti­theft vehicle immobiliser in the same unit.

The electronic start installation compri­ses the following:

- the main unit

- the immobiliser aerial

- the master/service key with incorporated

transponder

- H.T. coil

- Diagnostics LED

The diagnostics led also carries out the
function of dissuasory flasher. This func­tion is activated every time the ignition
switch is turned to the “OFF” position,
and, so as not to discharge the battery,
remains active for only 48 hours.

When the ignition switch is in position
“ON”, the dissuasory flasher is switched
off, and then it gives a flash to confirm
that the switch is in the “ON” position.

The time the flash lasts depends on the
program in the electronics unit.

When the LED is switched off and
remains off even when the switch is tur­ned “ON”, the following checks should be
performed:

- check for voltage at the battery

- check state of fuses: main fuse 15A,

LED protection fuse 5A

Connect the immobiliser tester to the
diagnostics socket which is located
behind the front left fuse box cover.

If the LED remains off, check the power
supplies at the electronics unit as shown
below:

Disconnect the electronics unit connec­tor, and check the following conditions:

- battery voltage exists between terminal

no. 4 (Red) and earth

- battery voltage exists between terminals

no. 4 (Red) and no. 8 (negative) as
shown in the diagram.

17

ELECTRICAL SYSTEM

- battery voltage exists between terminals
no. 5 and no. 8 with the ignition switch in
the “ON” position, and the emergency
stop switch in “RUN”.

If any faults are discovered, replace the

electronics unit.

New installation

When the ignition installation is not
coded, it permits the engine to run, but
with a limit of 2,000 rpm, and when the
throttle is opened to accelerate, a distinct
loss of power is noted.

In order to code the installation, is it
necessary to use the MASTER key
(coloured brown), and the SERVICE key
(coloured blue), as shown below.

- insert the MASTER key, turn the switch

to “ON” and hold this position for 2
seconds (limiting values: 1-3 seconds).

- Insert all the available blue keys, one

after the other, turning each key to the
“ON” position for 2 seconds.

- Insert the MASTER key again, and turn

to the “ON” position for 2 seconds.

The maximum time limit allowed for
changing keys is 10 seconds.

In any one memorisation session an
upper limit of 7 service keys (coloured
blue) will be accepted. It is essential to
observe the sequence and the time limits,
if not it will be necessary to start the whole
procedure again from the beginning.

Once the electronics units has been
programmed, an unbreakable link will
have been established between the elec­tronics unit and the MASTER key trans­ponder.

While this link is maintained, it is possi­ble to carry out new service key memori­sations, if one becomes lost, is replaced,
and so on. Each memorisation session
deletes the previous session.

When the memorisation of the services
keys is lost, it is vital to check thoroughly
the correct state of the high tension cir­cuit:

Protector cap resistance ~ 5,000 Ω

Under all circumstances it is recom­mended to use resistance spark plug caps
as shown in the figure.

18

ELECTRICAL SYSTEM

Diagnostics codes

After the flash indicating the fault that has occu-

rred has turned to “ON”, a phase indicating fault
codes may be started.

This is performed with an initial condition of LED

off for a period of 2 seconds, followed by the trans-

mission of the diagnostics codes with flashes of 0.5
seconds.

After indicating the breakdown code, the LED
remains permanently on with no flashing, to show
that it is not possible to start the engine, see the
diagram.

19

Diagnostics code: 2 flashes

If a 2-flash code is found, carry out the following

checks:

Check whether the fault persists after changing
the key (including the MASTER). If the fault exists
with any of the keys, disconnect the electronics unit
aerial connector, and check for continuity in the
aerial using multimeter part no. 020331Y.

Value of resistance: ~ 7 – 9 Ω

If the value is different, change the aerial.

If no fault is found, replace the electronics unit.

– before carrying out the memorisation
procedure with the new electronics unit, check that
no fault code is shown. This check is necessary in
order to avoid wasting a new unit to no purpose.

Diagnostics code: 3 flashes

If a 3-flash code is found, carry out whether the
fault persists when the MASTER key is also inser­ted into the ignition lock.

If the fault disappears when the MASTER key is
used, it is necessary to carry out a re-coding proce­dure with the service key (coloured blue).

If the fault persists, this means that the MASTER
key and the electronics unit are not linked; in this
case, it is necessary to replace the electronics unit
and carry out the ensuing key coding procedure.

The immobiliser installation is in operating condi­tion when after switching to the “ON” position, a
flash of only 0.7 seconds is recorded (see figure).

In this case, it is possible to start the engine.

Caution

Example with unit programmed, transpon­der present, key programmed and aerial in
operating condition.

Ignition enabled – vehicle in normal wor­king order

CODE – TWO FLASHES

Example with unit programmed, missing transponder, and/or
aerial in poor condition.

Ignition disabled – vehicle immobilised

CODE – THREE FLASHES

Example with unit programmed, aerial in operating condition
and unknown transponder code.

Ignition disabled – vehicle immobilised

ELECTRICAL SYSTEM

Installation of the Ignition

Once the immobiliser installation has been ena­bled, it will be possible to obtain a spark at the
spark plug through the H.T. coil, and the signals
proceeding from the Pick-Up.

The basic power supply is the battery, and the
installation is calibrated such that any possible bat­tery voltage loss is detected immediately by the
electric start system, and has virtually no effect
upon the ignition system.

The Pick-Up is connected to the electronics unit
via a single cable, which means that the return con­nection from the electronics unit to the Pick-Up is
via the frame and the engine earth cable.

To avoid any problems in the ignition installation
during the electric start phase, it is very important to
ensure a good earthing connection between the
engine and the frame.

20

Failure in the power supply to the spark
plug

If there is not current to the spark plug
while the LED indicates that ignition is pos­sible, carry out the following check opera­tions:

-Check the Pick-Up

Disconnect the electronics unit connec­tor, and to verify the continuity between the
terminal no. 2 (green) and the terminal no.
8 (Black). The control anticipates the Pick­Up and its plinea of feeding.

Resistance value: 105 ÷ 124 Ω

If is an interruption of the circuit,check
for continuity between the magneto and the
engine earth (see engine manual). If ano­malous values are found, replace the Pick­up or repair the cable.

- Verification of the H.T. Primary Coil

Disconnect the electronics unit connec­tor and check for continuity between termi­nals no. 3 and no. 8 (see diagram).

Resistance value: 0.4 ~ 0.5 Ω

If non-standard values are found, repeat
the test directly on the positive and negati­ve terminals of the Primary H.T. coil.

If non-standard values are found, repair
the cable or replace the H.T. coil.

- Verification of the H.T. Secondary Coil

Disconnect the spark plug cap from the
H.T. cable, and measure the resistance
between the end of the H.T. cable and the
H.T. coil negative terminal (see diagram).

Resistance value: ~3000 ± 300 Ω

If non-standard values are found, repla­ce the H.T. coil. In order to carry out a more
complete diagnostics test, it is possible to
perform a check on the peak voltage by
means of the multimeter adapter, drawing
number 020409Y.

ELECTRICAL SYSTEM

Pick-Up

Disconnect the electronics unit connec-

tor and connect the positive terminal to
connector no. 2, and the negative terminal
to connector no. 8 (see diagram).

Turn the engine using the starter motor,

and measure the voltage produced by the
Pick-Up.

Voltage reading: > 2 V

If non-standard readings are obtained,

replace the Pick-Up.

N.B.: the multimeter must be set to

read Direct Current

H.T. Coil

With the electronic unit and the H.T.

Coil connected as normal, measure the
voltage at the primary coil during the star­ter test, using the peak voltage adapter,
connecting the positive terminal to earth
and the negative terminal to the positive
terminal on the coil.

Voltage reading: > 100 V

If the voltage readings are out of range,

replace the electronics unit.

N.B.: the positive terminal of the pri-

mary H.T. coil is identified by its black
colour.

Battery Charger Installation

The battery charger installation involves

the use of a three-phase generator with
permanent magneto.

The generator is connected directly to

the voltage regulator.

In turn, the voltage regulator is connec-

ted directly to earth and to the positive ter­minal on the battery, through the 15A pro­tection fuse.

It can be seen therefore that the system

does not involve any connection with the
ignition switch.

The three-phase generator produces

significant recharge power, and even at
the lowest revolutions, it obtains a good
compromise between power requires and
stability of the idle speed. For this reason,
it is indispensable to set the idle speed
according to specifications.

21

Checking the voltage regulator

With the battery fully charged and the
lights switched off, measure the voltage
between the battery terminals with the
engine at high revolutions.

The voltage should not exceed 15.2 V.

If higher voltages are recorded, replace
the voltage regulator.

If the readings are lower than 14 V,
check the stator and related cabling.

Checking the stator

Disconnect the voltage regulator con­nector and check for continuity between
each yellow cable and the other two.

Resistance reading: 0.7 – 0.9 Ω

A check should also be carried out to
ensure that each yellow cable is insulated
from earth.

If non-standard readings are obtained,
repeat the check directly at the stator ter­minals, and if out-of-range readings are
still obtained, replace the stator or repair
the cable.

Checking the current draw of the char­ger installation

Connect the armature clip of an amme­ter to the positive cable of the voltage
regulator, measure the battery voltage,
and after switching on the vehicle lights
with the engine stopped, wait for the volta­ge to adjust to 12v. Start the engine, and
measure the current drawn by the installa­tion with the lights switched on and the
engine at high revolutions.

Where the reading of the current drawn
is lower than 10A, repeat the test using in
succession the voltage regulator and/or a
new stator.

22

ELECTRICAL SYSTEM

Checking the automatic choke section

For checks on the resistance and ope-

ration of this component, refer to the engi­ne section. For checks relative to the
power supply, keep the installation con­nector connected, and check that there
exists battery voltage at the two terminals
with the engine running (see diagram).

If no voltage is present, connect the

negative terminal of a multimeter to earth
and the positive terminal to the orange
coloured cable of the automatic choke
device; with the ignition switch in the “ON”
position, check for battery voltage; if there
is no battery voltage, check the cable con­necting to the ignition switch.

If voltage is present, repeat the check

with the ignition electronics unit connec­tor.

Keeping the choke connected, remove

the electronics unit connector, ignition
switch to “ON”, and check for voltage con­necting the multimeter with the positive
terminal to terminal no. 7 (White/Black)
and the negative terminal to terminal no. 8
(Black) (see diagram).

If voltage is not present, replace the

electronics unit; if voltage is present,
reconnect the cable connecting the choke
and the electronics unit.

The direction indicators do not operate

If the direction indicators do not work,

carry out the following verification opera­tions:

Disconnect the electronics unit connec-

tor, and check that there is battery voltage
between terminal no. 4 (Red) and earth.

Check that there is also battery voltage

between terminal no. 4 (Red) and terminal
no. 8 (Black)

If no voltage is present, check the

cabling and the connections, and of there
is no voltage, carry out the following verifi­cation operations:

- bridge the terminals no. 1 (Black/Blue)
and no. 4 (Red) (see diagram), and ope­rate the direction indicator switch alter­nately to the left and to the right, and
check that the lights come on.

If the lights come on, replace the indi-

cator unit, because it is faulty.

If the lights do not come on, check the
cabling connecting the indicator unit to the
indicator switch, and repeat the test.

23

ELECTRICAL SYSTEM

POWER SUPPLY FUSE CIRCUITS PROTECTED

15 A direct current Lighting relay

15 A direct current General contact

7.5 A direct current Headlamp flash

5 A direct current Side lights

5 A direct current Diagnostics LED

5 A direct current Stop light - horn - instrument panel

List of Bulbs

Purpose Type Power

Dipped headlight bulb Halogen 12v 35w

Full beam headlight Halogen 12v 35w

Front position light all-glass 12v 5w

Front direction indicator lights Spherical 12v 10w x 2

Tail light/stop light bulb Spherical 12v 5w / 12V 10w

Rear direction indicator light bulbs Spherical 12v 10w x 2

Instrument panel illumination light bulbs all-glass 12v 1.2w x 4

Position light/dipped headlight pilot light bulb all-glass 12v 1.2w

Storage compartment illumination light bulb Spherical 12v 5w

Registration plate illumination light bulb cylindrical 12v 5w

ELECTRICAL SYSTEM

Fuses

The electrical installation is equipped

with:

- four protection fuses mounted on the
battery bracket;

- four protection fuses for the various cir­cuits in the installation, place in the inte­rior of the fuse box cover situated in the
rear inner left of the shield.

The table shows the characteristics of

the various fuses, used in the vehicle.

before replacing any
blown fuse, recharge the battery and
correct the fault which caused the fuse
to blow.

Do not attempt to replace any fuse
using any other material (for example,
a length of electric wire) or with a fuse
of a higher rating than specified.

Caution

24

SUSPENSIONS

FRONT FORKS

Suspension stroke ......................................76 mm.

Leg diameter...............................................35 mm.

Oil capacity (each leg).................................95 c.c.

Type of oil....................................................SAE 10 W

REAR SUSPENSION

Hydraulic shock absorber

Length of shock absorber ...........................300 mm

Stroke of shock absorber............................60 mm

Length of spring ..........................................223 mm

Spring compression force to 35 mm ...........147 kg/m

Spring compression force to 60 mm ...........830 kg/m

Stem............................................................10 mm

25

Vacuum cock pre-filter cleaning

- drain the fuel tank completely

- withdraw the fuel supply and return lines

- slacken off the clip and withdraw the

cock

- Clean the tank and the fuel cock pre-fil-

ter

- Reassemble the cock, taking care that

the O-R ring is in its place

- Align the cock as shown in the figure

and tighten up the clip.

Vacuum cock

- disconnect the fuel supply line and the

carburettor vacuum line

- check that there is no leaked fuel in eit-

her line

- close the fuel outlet

- using the MITIVAC pump (part

no.19.1.20329) apply 0.1 bar of vacuum
to the cock

- ensure that the vacuum remains stable

and that there are no fuel leaks into the
system

- connect the vacuum line to the manifold

- place the fuel line with its outlet at the

same level as the cock

- turn the engine using the starter motor

for 5 seconds with the carburettor throt­tle at minimum position

- remove the fuel into a graduated buret-

te.

Minimum flow: 20 cc

N.B.: The measurement may be affec-

ted by an incorrect number of turns, or by
incorrect placing of the tube. In this case
the tendency would be to obtain a lower
quantity of fuel.

The vacuum intake on the manifold has
a reduced section in order to improve the
pulses of vacuum, thus ensuring a cons­tant flow at the cock.

26

FUEL SUPPLY AND CARBURETTOR

Air filter

- to clean the air filter, carry out the follo­wing operations: remove the filter box
cover, D, after first withdrawing the 6
securing screws, C; remove the 2 filter
box securing screws (see figure) and
then turn it to remove the 2 upper and
four lower screws, and withdraw the air
filter. Clean the air filter with soap and
water, and then dry it using compressed
air; finally submerge the filter in a 50-50
mixture of AGIP Oil Filter oil and petrol.
Lastly squeeze out the excess oil. Allow
to dry and reinstall.

- Ensure that the mass of the filter is
correctly installed

- Check that the air flow channels are not
deformed

- Check that the air filter box is correctly
fitted and is properly sealed.

N.B.: failure to observe these instruc-

tions will cause incorrect vacuum in the
interior of the filter box: this will lead to
incorrect carburettor operation.

Stripping the carburettor

- in order to disconnect the carburettor
from the engine, carry out the sequence
of operations described in the Cylinder,
Cylinder Head, and Distribution chapter

- Remove the discharge tube and the
ventilation tube from the float chamber

- Withdraw the heater.

- Remove the protection, the stirrup, and
the choke, by loosening the 2 screws
shown in the figure.

27

FUEL SUPPLY AND CARBURETTOR

- remove the 2 securing screws and the
choke bracket together with the gasket.

- remove the securing screw as shown in
the figure, the rocker arm and the acce­lerator pump drive spring

- withdraw the 2 securing screws as
shown in the figure, the vacuum cham­ber cover, and the spring.

– while stripping the
cover be careful to ensure that the spring
is not released unexpectedly.

- Remove the vacuum valve and the

membrane

- Remove the 4 screws shown in the figu-

re, and the chamber and its gasket.

Warning

28

FUEL SUPPLY AND CARBURETTOR

- Remove the accelerator pump piston
from the chamber together with the
collar, the deflector, the O-R ring, and
the spring, as shown in the figure.

- Support the carburettor properly, and
then, using a hammer and punch, remo­ve the float pin, working from the throttle
control side.

- Remove the float and the needle.

- remove the carburettor transporter cap
for the choke jet as shown in the figure.

- Remove the main jet.

- Remove the emulsifier.

29

FUEL SUPPLY AND CARBURETTOR

- Remove the atomiser, by tilting the car­burettor body.

N.B.: It is necessary to carry out this

operations, in order to avoid losing the
atomiser, during the carburettor body cle­aning phases. When the atomiser is stuck
in its seating, do not strip it out, to avoid
damaging the parts.

- Remove the minimum jet.

- Remove the minimum flow adjustment
screw and the O-R ring, the washer, and
the spring.

- Do not attempt to re­move the components inserted into the
carburettor body, such as: the fuel supply
pipe, the needle seat, the choke jet, the
progressive manifold chamber, and the
supply jet, the minimum and maximum air
set screw, the butterfly valve drive shaft.
Avoid removing the screws securing the
butterfly valve to its shaft: these screws
have been punched after assembly and
removing them will damage the shaft.

Assembling the carburettor

- Before reassembling the carburettor it is

important to carry out a thorough clea­ning of the carburettor body using petrol
and compressed air.

- Pay particular attention to the fuel inlet

channel and the needle seat.

Warning

30

FUEL SUPPLY AND CARBURETTOR

- For the main jet circuit, check the airway
shown in the figure very carefully.

- For the minimum jet circuit, take care to
ensure that the following points are pro­perly cleaned: airway, the outlet section
controlled by the fuel flow set screw,
and the progressive outlets near the but­terfly valve.

- For the choke jet circuit, take care to
ensure thorough cleaning of the channel
connecting to the jet, because there are
hidden ways in the interior of the jet sup­port which are inaccessible.

- Carefully blow the supply jet clean.

- This outlet section is extremely small
and is orientated towards the butterfly
valve. Failure to orientate this jet
correctly will lead to incorrect atomisa­tion.

- Verify that the five spheres closing off
the production ways are present in the
carburettor body.

- Verify that the flat seating faces for the
chamber and the membrane show no
unevenness.

- Verify that the vacuum valve seat way is
not scratched.

- Verify that the butterfly valve and its
shaft do not show any unusual signs of
wear.

31

FUEL SUPPLY AND CARBURETTOR

- Verify that the needle seat does not show any unusual
signs of wear.

- If there are any anomalies, replace the carburettor.

N.B.: in order to avoid causing damage do not introduce

metal objects into the ways.

- Carefully wash and dry the minimum jet,
using a blast of air, and reassemble.

- Carefully wash and blow dry the compo­nents of the main jet, atomiser, emulsi­fier, and jet.

- Insert the atomiser in the carburettor
body with the shorter cylindrical part
facing towards the emulsifier.

- Assemble the emulsifier, taking care to
ensure that the atomiser is correctly ins­talled, and secure.

- Mount the main jet.

- Verify that the conical needle shows no
signs of wear on the sealing surface
with the shock absorbing pin and the
return spring.

- In case of signs of wear replace the
needle.

- Verify that the float shows no signs of
wear on the pin seating or on the needle
contact plate, nor signs of entry of fuel.

- In case of signs of wear replace the
float.

- Assemble the float with the needle,
inserting the pin from the fuel inlet tube
side.

N.B.: take care to ensure correct inser-

tion of the return spring on its plate on the
float.

32

FUEL SUPPLY AND CARBURETTOR

Verification of level

- Take care to ensure that the mating sur­face of the float is parallel with the plane
of the chamber, with the carburettor in
an inverted position.

- If different alignments are found, modify
the orientation of the metal needle con­trol plate until the position described
above is found.

- If the plate is deformed, ensure that it
remains parallel to the float pin.

- wash and dry the carburettor transport
cap carefully and assemble it over the
choke jet.

N.B.: Failure to assemble this piece

leads to deteriorated cold starting perfor­mance, since the choke jet in this event
takes old fuel from the bottom of the
chamber.

- Remove the chamber drain screw, wash
and dry the chamber carefully, paying
particular attention to cleaning the fuel
supply pump intake and outlet valve.

- Since these are one-way valves, blow
the intake valve delicately with compres­sed air from the inner side of the cham­ber, and the outlet valve from the piston
pump seat side.

- Verify that the fuel supply pump piston
and its corresponding seat in the cham­ber show no signs of wear.

- In the event that signs of wear are
found, replace the defective parts.

- Verify that the fuel supply pump piston
return spring is not worn

- Fit a new O-R ring and a new bellows
gasket, re-assemble the piston
assembly to the chamber.

- Fit a new O-R ring on the chamber drain
screw, and lock the screw.

33

FUEL SUPPLY AND CARBURETTOR

- Check that the screw seals correctly by
adding a small quantity of fuel into the
chamber.

- Fit a new gasket over the chamber.

- Assemble the chamber to the carburet­tor body, and tighten the 4 screws to the
specified torque setting.

- Wash and blow dry the flow screw care­fully, fitting a new O-R ring.

- Pre-fit the components onto the screw in
the order shown: spring, washer, and
the O-R.

- Tighten the fuel flow screw into the car­burettor body.

- The final position of the fuel flow screw
will be determined by analysing the
exhaust gases.

- Prepare the carburettor for the adjust­ment by unscrewing the screw by two
turns from the fully closed position.

- check that the fuel supply pump drive
rocker shows no signs of unusual wear.

- Check that the rocker stroke stop screw
projects by 3 + 0.1 mm.

- Check that the rocker return spring has
not become weakened.

- Pre-assemble the rocker and the spring
as shown in the figure.

- Assemble the rocker on the carburettor
while keeping the butterfly valve open.

- Assemble the rocker securing screw
and tighten to the specified torque set­ting.

- Ensure that the assembled mechanism
works correctly.

34

FUEL SUPPLY AND CARBURETTOR

Checking the vacuum valve and the
conical needle

- Unscrew the bayonet fitting 1/8 of a turn
and withdraw, removing the spring and
the vacuum valve needle.

- Check that the needle shows no signs of
wear and that the stop is set on the
second notch.

- Check that the vacuum valve snows no
signs of scratching around its external
diameter.

- Check that the two vacuum supply ports
are not blocked.

N.B.: The two ports have different dia-

meters.

- Check that the membrane is not torn
and has not become hardened.

- If it is seen to have deteriorated, replace
it.

- Reassemble with the conical needle
over the vacuum valve.

- Ensure correct positioning of the spring
on the needle and the bayonet fitting on
its seat.

- Assemble the fitting by turning 1/8 of a
turn.

- Assemble the vacuum valve onto the
carburettor body, taking care that the
conical needle is correctly inserted into
the interior of the atomiser.

- Set the phase of the vacuum valve rota­tion by inserting the tail of the membra­ne into the appropriate seat: in this posi­tion, when the membrane is correctly
assembled to the valve, the main
vacuum supply port is situated over the
diffuser shaft and on the side of the but­terfly valve, see figure.

35

FUEL SUPPLY AND CARBURETTOR

- Reassemble the spring onto the valve.

- Reassemble the vacuum chamber cover, aligning the refe­rence on the cover with the orientation mark on the mem­brane.

- Lock the screw by tightening to the specified torque set­ting.

- Wash and blow dry the choke bracket.

- Fit a new gasket on the carburettor body
and lock the two securing screws.

Checking the automatic choke

- Check that the automatic choke piston
shows no signs of scratching or oxida­tion.

- Check that the piston runs smoothly
along the seating to the bracket.

- Check that the piston sealing gasket
show no sign of deformation.

- The automatic choke should enter into
the housing by a distance which is a
function of the ambient temperature.

- Measure the amount the piston projects
out of its housing as shown in the figure
and verify the appropriate reading.

- Check that the choke is correctly adjus­ted to the ambient temperature.

Measurement of the amount of projec-

tion: 13 mm

- The choke should disconnect progressi­vely when heated electrically.

- Check the resistance of the choke when
adjusted to the ambient temperature.

Resistance reading: 30 – 40 Ω

- Supply the automatic choke using a 12
V battery and confirm that the piston
reaches its maximum projection measu­rement.

Maximum projection reading: 19 mm
Maximum extension time: 5 minutes

- The effective heating time depends on
the ambient temperature.

- If projection and resistance readings, or
the timings, are different from those spe­cified, replace the automatic choke.

36

FUEL SUPPLY AND CARBURETTOR

- While assembling the automatic choke
onto the carburettor, take care that the
O-R ring is correctly located. Insert the
plate with the milled side resting on the
choke, and tighten the 2 securing
screws.

- Align the choke as shown in the figure.

- Assemble the protector baffle.

- Check the heater resistance at ambient
temperature.

Resistance at ambient temperature: ~ 15 Ω

- If different readings are obtained, repla­ce the part.

- Reassemble the heater onto the carbu­rettor.

- Reassemble the vent tube and the
chamber drain tube.

- Install the carburettor onto the engine,
as described in the Cylinder, Cylinder
Head, and Distribution chapter.

Idle adjustment

- The engine does not require very fre­quent idle adjustment, but it is very
important that the adjustment is carried
out while observing certain rules.

- Before adjusting the carburettor, ensure
that the engine is properly lubricated,
that the valve play and distribution
timing are as specified, the spark-plug in
best working order, the air filter clean
and tightly sealed, and the exhaust pipe
installation is completely gas-tight.

- Heat the engine for at least 5 minutes
running at 50 kph.

- Connect the vehicle to the exhaust gas
analyser, by inserting the analyser
probe into an extension tube fitted her­metically to the silencer outlet.

Maximum length of tube: 40 ÷ 50 cm

37

FUEL SUPPLY AND CARBURETTOR

N.B.: the extension tube is indispensable in order to avoid

analysing the exhaust gas contaminated with atmospheric
oxygen. It is indispensable to use a previously heated
exhaust gas analyser and in proper working order in order to
adjust the reading of the gases to zero and the correct flow
of gas. Failure to observe these norms will lead to incorrect
readings.

- Connect the multimeter thermometer
(part number 10.1.20331) to the mani­fold, using an oil filled plug specially
made for inserting the probe.

- Start the engine and before carrying out
the idle adjustment, ensure that the tem­perature of the oil has reached between
70 ÷ 80ºC.

- By using the both the analyser rev coun­ter and a separate rev counter (part
number 19.1.20332) , adjust the idle
adjustment screw until a speed of
1600 ÷ 1650 rpm has been obtained.

N.B.: The ignition installation is of the

lost spark type, and produces considera­ble power. Difficulties in obtaining rea­dings may ensue when using non-recom­mended rev counters.

The rev counter is considered to be
correctly fitted when it is able to read even
very high speeds at 6,000 ÷ 8,000 rpm.

- Adjust the flow adjustment screw until a

percentage of carbon monoxide (CO) of

3.5 + 0.5% is obtained; loosening the
screw increase the CO reading (rich
fuel-air mixture), while tightening the
screw reduces the CO reading (weak
fuel-air mixture).

- When the correction of the flow adjust-

ment screw leads to an increase in revo­lutions, adjust the rpm again, and then
the fuel flow adjustment screw again,
until stable readings are obtained.

- Idle speed carburation is considered to

be correct when the temperature, revo­lutions, and Carbon Monoxide percenta­ge readings are observed. Other infor­mation may be obtained from the analy­ser:

- Percentage CO; readings higher than

13.8% are considered to be correct.
Lower readings indicate loss of gas­tightness in the exhaust pipe installation.

38

FUEL SUPPLY AND CARBURETTOR

- Unburnt hydrocarbons are measured in parts per million
(ppm) and the HC reading drops as the engine speed
increases, and at idle speed it is normal to find readings of
200 ÷ 400 ppm. Emission values such as these are consi-
dered normal for an engine with a motorcycle distribution
diagram. The indication of much higher values may arise
from loss of power in the engine due to excessively weak
mixture (low CO), faults in the ignition, or perhaps inco­rrect distributor timing, or the drain valve being blocked or
not hermetically sealed.

- Strip the carburettor down to its component parts, wash all the
parts carefully with solvent. Dry all the airways in the carburettor
body using compressed air to ensure total cleanliness.

- Check the condition of all the parts very carefully.

- The throttle valve should rotate freely in its seat. In the event of
excessive play, replace the carburettor.

TECHNICAL CHARACTERISTICS VERSION 125/150

FUEL SUPPLY AND CARBURETTOR

Version

Type: WVF WALBRO

Diffuser diameter

Conical needle notch
from above

Main jet

Minimum jet

Fuel needle seat

Minimum air jet

Basic adjustment of
fuel fl ow screw
(prior to CO adjustment)

Gas valve diameter

Choke jet

Type of conical needle

Maximum air jet

125 c.c. 150 c.c.

WVF6E

28 mm

2ª

84

33

1,5 mm

100

3 gm

Ø 33

50

51c

70

WVF6AG15

28 mm

2ª

82

34

1,5 mm

50

3 gm

Ø 33

50

465

150

Warning

The gasoline is infl ammable. To always substitute the meetings
to prevent losses of gasoline.

TECHNICAL CHARACTERISTICS VERSION 200

Versión

Depression type

Printing on the body

Printing

Max. jet

Minimum jet

Max. air jet

Minimum air jet

Gas valve spring

Idle mixture adjustment screw initial opening

Conical pin printing

Conical pin notches position from top

Emulsifi er nozzle

Starter air jet

Starter emulsifi er jet

Starter jet

Starter device resistance

Choke

200 c.c.

CVEK 30

CVEK

303A

100

38

70

115

150 ÷ 250 gr

2 ½ ± ¼

NDWA

Fixed position

Ø 2,8

Ø 1,5 (body)

Ø 1,2

42

~ 20 Ω (a 24º)

Ø 29

Note

* The identifi cation letter can vary every time
the carburettor is update.

39

CALIFORNIA EVAPORATIVE
EMISSION SYSTEM

This system consist of:
A) Canister
B) 1 - Way purge control valve
C) Carburetor vent line
D) Cylinder
E) Carburetor
F) Purge line
G) Fuel pump
H) Feed line
I) Fuel tank
L) Vacuum line
M) Fuel tank vent line
N) 2 - Way & Roll-Over valves
O) "T" valve

40

EVAPORATIVE EMISSION SYSTEM

Replacing the front brake pads

- The brake pads are not

symmetrical, and are not interchangeable.

The pads must be replaced when the
thickness of the friction material is lower
than 1.5 mm.

Fit new brake pads and insert the secu­ring stud into the corresponding stop clip.

N.B.: When changing the brake pads, it

is necessary to check the guide stud for
wear in the area where it makes contact
with the brake pads (replace if there are
evident signs of wear). Moreover, while
inserting the stud, take great care not to
stretch the pad pressure spring.

- Just as is specified in the
programmed maintenance schedule, it is
recommended to lubricate the front and
rear brake levers at the point where they
apply pressure on the brake cylinder push
rod.

Caution

Caution

41

BRAKE SYSTEM

Aesthetic Checks

· Paintwork

· Plastic fittings

· Scratches

· Dirt

Check for locking

· Security locking

· Securing screws

Electrical installation

· Main switch

· Headlights: full beam, dipped beam, position
lights, parking light, and associated pilot lights

· Adjustment of beam according to regulations in
force

· Tail light, parking light, stop light

· Front and rear brake stop light switches

· Direction indicators and associated pilot lights

· Instrument panel lights

· Instrument panel: petrol and temperature indicator
lights

· Instrument panel pilot lights

·Horn

· Choke

Verification of levels:

· Hydraulic brake fluid system level

· Rear hub oil level

Road test:

· Cold start

· Operation of instruments

· Response to throttle control

· Stability under acceleration and braking

· Front and rear brake performance

· Front and rear suspension performance

· Abnormal noises

Static test after road test:

· Hot start

· Choke operation

· Stability in idle (turning handlebar)

· Smooth steering rotation

· Any leaks

Functional verifications:

· Hydraulic brake installation Brake lever travel

· Mechanical brake installation Brake lever travel

· Clutch Verification of

correct operation

· Engine Verification of throt-

tle travel

· Other Verification of documentation

Verification of frame
number and engine
number
Basic tool kit
Installation of regis­tration number plate
Check on locks
Check on tyre pres­sures
Assembly of rear­view mirrors and
any other accesso­ries

- The battery should be charged before
use to ensure maximum performance. Failure to
ensure sufficient battery charge before first use with
a low electrolyte level will lead to premature battery
failure.

- Before charging the battery,
remove the caps from each cell.
Keep open flames and sparks away from the battery
while charging.
Remove the vehicle from the machine, disconnec­ting the negative terminal first.

- When installing the battery, first ins­tall the positive cable, followed secondly by the
negative cable.

- The battery electrolyte is poiso­nous and can cause serious burns. Battery elec­trolyte contains sulphuric acid. Avoid contact with
the eyes, skin, and clothes.

In the event of contact with the eyes of the skin,
wash with abundant water for 15 minutes, and con­sult a doctor immediately.

In the event of swallowing battery liquid, immedia­tely drink copious quantities of water or vegetable
oil. Call a doctor immediately.

Batteries produce explosive gases; keep away
from open flames, sparks or cigarettes. Keep the
area ventilated while charging the battery in enclo­sed spaces. Always protect the eyes when working
near batteries.

KEEP AWAY FROM CHILDREN

- Do not use fuses with a higher rating
than recommended. Use of a fuse with an incorrect
rating may cause damage to the entire machine, or
even produce a risk of fire.

- The inflation pressure of the tyres is
to be checked and adjusted when at ambient tempe­rature.

- Do not exceed the specified inflation
pressures, because the tyre may

Safety locking of securing elements:

Upper shock absorber securing front 20 ÷ 30 N.m
Lower shock absorber securing front 20 ÷ 25 N.m
Upper shock absorber securing Rear 20 ÷ 25 N.m
Lower shock absorber securing Rear 33 ÷ 41 N.m
Wheel hub nut 75 ÷ 85 N.m
Rear wheel rim to hub securing screw 20 ÷ 25 N.m
Swinging arm stud to frame 64 ÷ 72 N.m
Swinging arm stud to engine 33 ÷ 41 N.m
Motor arm stud to frame arm 33 ÷ 41 N.m

Caution

Warning

Caution

Warning

Caution

Caution

Caution

42

PRIOR TO DELIVERY

ENGINE - GENERAL AND MAINTENANCE INFORMATION

TECHNICAL SPECIFICATIONS:125 CC 4-STROKE ENGINES

Typ e:
Bore:
Stroke:
Cubic capacity:
Compression ratio:
Carburettor:
Lubrication system:
Fuel:
Cooling system:
Maximum power:
Ignition advance:
Spark Plug:
Transmission system:
Valve clearances:
Recommended engine oil:
Quantity:
Hub oil:
Quantity:

TECHNICAL SPECIFICATIONS: 150 CC 4-STROKE ENGINES

Single-cylinder 4-stroke
57 mm
48,6 mm
125 cm³
10,1 ÷ 11,1 : 1
WALBRO VWF6
Forced lubrication using chain-driven lobe pump inside crankcase with double mesh fi lter.
Petrol (minimum 95 octane, lead free) via carburettor
Forced air
76 Kw at 7500 r.p.m.
Variable microprocessorcontrolled 10º±1 at 1,650 rpm, or 26º±1 at 6,000 rpm
Champion RG 4 HC
Automatic expanding pulley variable speed drive using trapezoidal belt, autom.c clutch, gear reduction.
inlet: 0.10 mm - Exhaust: 0,15 mm
AGIP 4T SAE 10W40
1000 cc.
AGIP GEAR 80W90
100 cc.

Typ e:
Bore:
Stroke:
Cubic capacity:
Compression ratio:
Carburettor:
Lubrication system:
Fuel:
Cooling system:
Maximum power:
Ignition advance:
Spark Plug:
Transmission system:
Valve clearances:
Recommended engine oil:
Quantity:
Hub oil:
Quantity:

TECHNICAL SPECIFICATIONS: 200 CC 4-STROKE ENGINES

Version:
Engine:
Bore x stroke
Cubic capacity
Compression ratio
Ignition advance (before T.D.C)
WALBRO
KEIHIN Carburettor
Spark plug
Valve clearance: intake 200
Valve clearance: exhaust 200
Timing system 200

Air filter 200
Starter system 200
Lubrication 200
Power supply 200
Transmission

Rear hub
Engine oil
Tank capacity
Reserve

single-cylinder 4-stroke
62,6 mm
48,6 mm
149,58 cm³
10,1 ÷ 11,1 : 1
WALBRO VWF6
Forced lubrication using chain-driven lobe pump inside crankcase with double mesh fi lter
Petrol (minimum 95 octane, lead free) via carburettor
Forced air
8,13 Kw at 7000 r.p.m.
Variable microprocessorcontrolled, 10º±1 at 1,650 rpm, or 26º±1 at 6,000 rpm
Champion RG 4 HC
Automatic expand. pulley variable speed drive using trapezoidal belt, automatic clutch, gear reduction.
Inlet: 0.10 mm - Exhaust: 0.15 mm
AGIP 4T SAE 10W40
1000 cc.
AGIP GEAR 80W90
100 cc.

200 cc
Four-stroke mono-cylinder
72 x 48,6 mm
198 cm³
11,5 : 1
10º ÷ 1º at 2000r.p.m - 32º ± 1º at 6500 r.p.m
WVF 7H* Ø 29
CVEK-30
CHAMPION RG 6 YC
0,10 mm
0,15 mm
Single overhead camshaft driven by chain on left side, three-arm rockers with threaded
adjuster.
Sponge soaked in 50 percent pertol-oil mixture.
Electric starter motor with bendix-type drive-gear and torque-limiter.
Lubrication with chain driven lobe pump in crankcase, mesh strainer and cartridge filter.
Fuel (minimum octane number 95, leadless), with vacuum pump and by carburettor.
With automatic expandable pulley variator, trapezoidal belt, automatic clutch, gear reducer
and transmission compartment with forced circulation.
100 cc
~ 1000 cc
Tank capacity 12l. (indicative value)
Reserve 1,8l. (indicative value)

Por gasolina

43

Disassembling the engine from the
frame

- Disconnect the battery and the electrical
terminals.

- Disconnect the transmission and tubes.

- Disconnect the transmission air intake,
the air filter and the silencer.

- Remove the rear wheel.

- Drain the oil from the engine.

- Withdraw the engine.

Special tool number 19.1.25095

Re-installing the engine in the frame

- Offer up the engine to the frame follo­wing the reverse order from disas­sembly.

- Fill the crankcase with the recommen­ded oil up to the level indicated.

- Verify the correct operation of the throt­tle.

- Adjust the rear brake.

Torque settings

- Engine securing screw
20 ÷ 27 N-m.

- Rear shock absorber securing screw
20 ÷ 27 N-m.

- take extreme care

when handling petrol

- when installing the battery,
connect the positive cable first, and then
the negative cable.

- It is recommended to use
protective glasses when using percussion
tools.

Engine oil and filter

Checking the oil level

- Start the engine and bring it up to opera-

ting temperature.

- Stop the engine and wait for 5 ÷ 10

minutes for the oil to flow down to the oil
manifold.

- Withdraw the filler cap/dipstick and

clean it, and then screw it fully home.

- Remove the filler-cap/dipstick, and con-

firm that the oil reaches a level between
the MIN and MAX levels, as shown in
the figure.

Warning

Caution

Caution

44

ENGINE - GENERAL AND MAINTENANCE INFORMATION

Replacing the oil and the oil filter

N.B.: The engine oil should be replaced

with the engine hot.

- Drain the oil by removing the drain plug
and/or the pre-filter access as shown in
the figure.

- Let the oil flow out.

- Remove the filler cap.

- Remove and clean the pre-filter using
compressed air.

- Remove the silencer.

- Use a filter wrench to remove the oil fil­ter cartridge.

- Take care to ensure that the pre-filter O­rings and the drain plug are in good con­dition.

- Grease them and replace the pre-filter
and the drain plug, and lock them to the
specified par setting.

- Install a new oil filter cartridge, taking
care to grease the O-ring before
assembly, by screwing it down to the
point where it makes contact with the
gasket, and finally push it home with the
hand.

- Replace the silencer.

- Fill the oil manifold with oil until it rea­ches a level between the MIN and MAX
marks with the filler cap fully screwed
home.

- Close the filler cap.

- Start the engine to charge the oil filter
and the lubrication system with oil.

- Stop the engine, wait for approximately
5 ÷ 10 minutes.

- Top up the oil to the MAX level.

- Oil drain plug torque setting:
25 ÷ 28 N-m.

- Recommended oil:
AGIP CITY 4 T 10W-40

Transmission oil

Checking the oil level

- Place the machine on its stand on a
smooth level surface.

45

ENGINE - GENERAL AND MAINTENANCE INFORMATION

Changing the oil

- Remove the inspection cap.

- Remove the drain plug.

- Drain the oil completely.

- Re-fit the drain plug.

- Torque setting: 3 ÷ 5 N-m.

- Replace the seals on the cap and plug.

- Fill with oil through the inspection port,
right up to the level of the inspection
cap.

Truncated oil capacity 100 cc .

- Re-fit the inspection cap.
Torque setting 3 ÷ 5 N-m

- Check that there is no oil leakage

1. Remove cover “A” after first unscre-

wing the securing screw.

2. Withdraw the helmet box.

3. Lift off the spark plug cap.:

4. Pull cover “B” on the engine deflector

upwards and off.

5. Using the spark plug spanner supplied

with the basic tool kit, unscrew the
spark plug and remove.

- Examine the spark plug carefully, and if
the insulation is chipped or damaged,
replace.

- Measure the distance between the elec­trodes using a feeler gauge and if
necessary adjust the gap by bending the
outer electrode with great care.

- Ensure that the sealing washer is in
good condition.

- Assemble the spark plug, screwing it in
first by hand, and then locking it tight
using the spark plug spanner from the
basic tool kit.

Torque setting: 12 ÷ 14 N-m
Gap between the spark plug electrodes:

0.8 ÷ 0.9 mm
Recommended spark plug:

Champion RG 4HC

46

ENGINE - GENERAL AND MAINTENANCE INFORMATION

Air filter

- In order to clean the air filter carry out
the following operations: Remove cap
“D” from the air cleaner box, after first
unscrewing the 6 securing screws “C”;
remove the two box securing screws
(see figure) and then turn it to remove
the 2 upper screws and the 4 lower
screws and withdraw the air filter. Clean
it by washing it with soap and water, and
then dry using compressed air. Finally
submerge the air filter in a bath contai­ning a 50% mixture of AGIP FILTER OIL
and petrol. Lift the filter out of the mixtu­re, squeeze it to remove excess liquid,
allow to dry, and re-assemble.

- Take care to ensure that the filter mass
is correctly inserted.

- Verify that the air channels show no
signs of deformation.

- Check that the air filter box seals
correctly on its seating.

Disassembling the valve lifter cover

- Remove the 4 valve lifter cover securing
screws; withdraw the entire valve lifter
cover from the decanter cover and the
valve lifter cover sealing O-ring.

Decanter cover

- Remove the 4 decanter cover securing
screws.

- Withdraw the valve cover complete and
the O-ring.

- Verify the sealing tightness of the
O-ring, and the correct operation of the
one-way valve. Ensure that the valve
allows gases to leave but not to enter
the interior of the engine. If any fault is
discovered, replace the entire decanter
cover, and on re-assembly tighten the
securing screws to the correct torque
setting.

Torque setting: 3 ÷ 4 N·m

47

ENGINE - GENERAL AND MAINTENANCE INFORMATION

Fan cover deflector

- Remove the 4 securing screws as
shown in the figure.

Dis-assembly of the cooing fan

- Remove the 3 securing screws as
shown in the figure.

Checking correct distribution timing

- Turn the magneto until the timing refe­rence mark coincides with the end of the
crankcase as shown in the figure.

- Ensure that the 2V timing mark located
on the cam-shaft drive pulley is aligned
with the timing reference mark on the
head, as shown in the second figure.

- When the timing mark is located in a
position opposite the index mark on the
head, give the cam-shaft one additional
turn.

N.B.: In the event that the camshaft

timing assembly is not correctly timed,
carry out the timing operation as
described in.

48

ENGINE - GENERAL AND MAINTENANCE INFORMATION

Checking and adjusting the valve
clearance

- In order to carry out the check on the
valve clearance, it is first necessary to
line up the camshaft timing reference
marks as described in the previous
paragraph.

- Use a feeler gauge to check that the cle­arance between the valve and the tap­pet match the recommended specifica­tions. In the event that the valve clea­rances, on the inlet and the exhaust
valve are not the same as the recom­mended values below, they should be
adjusted. This can be done by loosening
the lock nut and using a screwdriver to
turn the adjuster as shown in the figure.

Inlet valve clearance: 0.10 mm
Exhaust valve clearance: 0.15 mm

Assembly of the valve lifter cover

- Perform the same operations as before
in reverse order to dis-assembly, and
tighten the securing screws to the
correct torque setting.

N.B.: Install a new O-ring on the valve

lifter cover.
Torque setting: 11 ÷ 13 N-m

Checking the final compression
pressure

- When the engine is cold, remove the
spark plug cap and the spark plug
access cover.

- Remove the spark plug. Fit into the
spark plug seating a compression tester
manometer gauge, using an adapter for
a 10 mm spark plug tightened to the
correct torque setting.

- Turn the engine using the starter motor
and with the throttle setting wide open,
until the manometer gauge reading sta­bilises. If the pressure is normal, remove
the test tool and re-assemble in the
reverse order to dis-assembly. If lower
pressures than the recommended ones
are found then check the engine rotation
speed during the test: if this is low,
check the starter installation, while if the
engine rotation speed is correct or
slightly higher check the compression

49

ENGINE - GENERAL AND MAINTENANCE INFORMATION

ratio, the correct sealing of the hot parts (compression
rings – valves etc. cylinder, cylinder head, and timing).

N.B.: If difficulty is encountered in inserting the

manometer gauge adapter, the procedure is to disconnect
the engine – swinging arm pin and move the engine
assembly towards the rear of the vehicle sufficiently to allow
the adapter to enter.

Torque setting: 12 ÷ 14 N-m

Drive cover

- In order the dis-assemble the drive
cover it is necessary to extract the small
plastic cap by levering with a screwdri­ver on the marks, and using the clutch
hub locking spanner as shown in the
figure (part number 19.1.20423), undo
the driven pulley shaft lock nut and the
washer.

- Extract the filler cap/dipstick from the
engine oil filler port.

- Remove the 10 securing screws and the
earthing cable secured below one of
them.

- Now it is possible to lift of the drive
cover.

In the event that this operation is
carried out directly on the machine with
the engine still installed, it is necessary
first to remove the cooling air hose and
the air filter box securing screws.

Dis-assembling the inlet port

- In order to dis-assemble the drive cover

inlet port, it is only necessary to unscrew
the three screws as shown in the figure.

Driven pulley shaft support bushing

- Remove the Seeger ring on the inner

face of the cover.

- Using the special tools (part numbers

19.1.20376 - 19.1.20375) extract the
bush from the crankcase.

- In order to avoid damaging
the paintwork on the cover, use an appro­priate surface to rest it on.

Caution

50

ENGINE - DRIVE

Fitting the driven pulley shaft
support bush

- Lightly heat the crankcase, on the inner
face so as not to damage the painted
surface, using the appropriate special
tools (part numbers 19.1.20376 -

19.1.20357 - 19.1.20412).

- Insert the bush into its seat, and fit the
Seeger ring again.

N.B.: Use a new bushing every time

the sub-assembly is re-assembled.

Dis-assembling the drive pulley

- Block the drive pulley using the special
tool (part number 19.1.20368) as is
shown in the figure.

- Remove the central nut and the bend-up
lock washer, withdraw the movement
pick-up and the 2 washers.

- Remove the fixed semi-pulley and the
steel washer.

- Pull off the drive belt, and withdraw the
moving semi-pulley together with its
bushing, taking great care not to let the
rollers loosely mounted on it to escape.

- Withdraw the roller counter-plate toget­her with its guide sliders.

Disassembling the driven pulley

- Withdraw the distance piece, the clutch
hub and the entire driven pulley sub­assembly.

N.B.: The sub-assembly can be dis-

assembled even with the moving pulley in
place.

51

ENGINE - DRIVE

Driven pulley

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

- Measure the internal diameter of the
clutch hub.

Standard measurement:
Ø 134.2 mm diameter

Maximum value:
Ø 134.5 mm diameter

N.B.: Check for eccentricity: maximum

eccentricity reading 0.20 mm

Dis-assembling the clutch

- Using the compass spanner (special
tool, part number 19.1.20565) lock the
clutch assembly from rotating.

- Use a 46 mm spanner (19.1.20444/9) to
unscrew the clutch lock nut.

- Withdraw the clutch and the clutch
spring.

- During the operation of

stripping down the hub, keep the clutch in
its housing, and thus counteract the force
of the spring.

Pin restraining collar

- Withdraw the collar by levering with two
screwdrivers.

- Extract the 3 guide pins and the moving
semi-pulley.

Fixed driven semi-pulley bearings

- Check that there are no signs of wear or
noise, and if there are, replace the bea­rings.

- Remove the lock ring by levering with
two screwdrivers with a flat face.

- Use a hammer and punch to extract the
ball bearing as is shown in figure A.

- Extract the ball bearing using a hammer
and a punch of the right diameter ente­ring from the side shown in figure B.

Caution

52

ENGINE - DRIVE

Fixed driven semi-pulley

- Measure the exterior diameter of the
pulley bearing.

Minimum diameter allowed:

40.96 mm Ø
Standard diameter: 40.965 mm Ø

Moving driven pulley

- Extract the two internal seals, and the 2
O-rings.

- Measure the internal diameter of the
moving semi-pulley bearing.

Minimum allowed diameter:

41.08 mm Ø
Standard diameter: 41.035 mm Ø

Assembling the fixed driven
semi-pulley bearings

- Fit a new roller cage bearing using the
special punch (part number 19.1.20424)
as is shown in figure A., aligning it with
the writing facing outwards.

- When fitting a new ball bearing work as
is shown in figure B, using the special
punch (part number 19.1.20375 -

19.1.20376); lastly fit the Seeger ring.

Assembling the moving driven
semi-pulley

- Check the internal diameter of the 2
seating points of the moving semi­pulley.

- Check the surfaces where the drive belt
makes contact with the pulley.

- Install new oil seals and O-rings on the
moving semi-pulley.

- Assemble the semi-pulley on the bea­ring using the appropriate protector sle­eve (19.1.20263).

53

ENGINE - DRIVE

- Check that there are no signs of wear
on the pins and the collar, and re­assemble the pins and collar.

- Using a grease gun with a curved nozz­le, lubricate the driven pulley assembly
using 6 grams of AGIP MU 3 grease;
this operation should be performed by
forcing grease through one of the ports
in the interior of the bearing until grease
is seen to come out of the opposite port.
It is necessary to perform the operation
in this way in order to avoid grease fin­ding its way outside the O-rings.

Spring

- Measure the free length of the moving
driven semi-pulley spring.

Standard length: 106 mm

- Check the thickness of the friction mate­rial on the clutch weights.
Minimum allowed thickness: 1 mm

- The clutch weights should not show any
signs of grease, and if this should occur,
examine the driven pulley assembly.

N.B.: When the clutch weights are run-

ning in, they should show a central con­tact surface, and there should be no diffe­rences between them. If they are seen to
be in different condition, this may cause
clutch judder.

- do not open the weights
using tools, so as to avoid any variation in
the loading on the return springs.

Assembling the clutch assembly

- Re-assemble the clutch assembly by

carrying out the same operations in
reverse order from dis-assembly. Use
the compass spanner to lock while
securing the clutch nut to its specified
torque setting.

- In order to avoid causing
damage to the clutch nut, use a socket
spanner with a bevel of reduced dimen­sions. During the clutch assembly lock nut
assembly operation, keep the assembly in
its housing until the clutch nut has been
set on its thread and given a few turns.

Torque setting: 55 ÷ 60 N-m

Caution

Caution

54

ENGINE - DRIVE

Drive belt

- Check that the drive belt is undamaged.

- Check the width of the belt.
Minimum width: 21.5 mm

Standard width: 22.5 ± 0.2 mm

Driving pulley

- Check that the internal bearing shown in
the figure shows no signs of wear, and
measure the internal diameter.

Maximum allowed diameter:
Ø 26.12 mm max diameter

Standard diameter:
Ø 26.021 mm diameter.

- do not lubricate or clean

the journal.

- Measure the external diameter of the
pulley sliding bush as shown in the figu­re.

Minimum allowed diameter:
Ø 25.95 mm max diameter

Standard diameter:
Ø 25.959 mm diameter.

- Check that the rollers are not damaged
or worn.

Minimum allowed diameter:
Ø 18.5 mm max diameter

Standard diameter:
Ø 18.9 mm diameter.

- Check that the roller counter-plate sli­ders are not worn.

- Check the condition of wear in the roller
seating slots and in the surfaces where
the belt makes contact on both semi­pulleys.

Assembly of the moving semi-pulley
and bearing

- Pre-fit the moving semi-pulley with the
roller counter-plate, placing the rollers
as shown in the figure.

- Fit the assembly together with the bea­ring onto the engine shaft.

Caution

55

ENGINE - DRIVE

- Open up the rear pulley and fit the drive
belt over it, taking care to observe the
correct direction of rotation. It is extre­mely important when securing the front
pulley assembly, to ensure that the drive
belt lies freely inside it, so as to avoid
any inappropriate pressure of the
moving semi-pulley.

Assembly of the fixed semi-pulley

- Reassemble the parts which compose
the subassembly (rear thickness plate,
fixed semi-pulley, front thickness plate,
movement pickup, washer and nut);
apply Loctite ”Super-Rapid” type 242 E
thread seal to all threads, and set the
nut to the recommended torque setting.

- Block the semi-pulley from rotating by
means of the compass spanner (part
number 19.1.20368)

N.B.: replace the nut with new every

time the drive is re-assembled.
Torque setting: 75 ÷ 83 N-m

Assembling the clutch hub

- Re-assemble the clutch hub and the dis­tance piece.

Assembling the drive cover

- Take care to ensure that the centring
pins are in place, together with the oil­tight gasket on the oil sump.

- Re-assemble the drive cover tightening
the 10 securing screws to the recom­mended torque.

- Re-fit the oil filler cap/dipstick.

- Re-fit the steel driven pulley shaft nut
washer and the driven pulley shaft nut
and apply Loctite “super-Rapid” type
242E thread seal onto the threads.

- Using the special tool (part number

19.1.20423) and a torque spanner, tigh­ten the nut to the recommended torque.

- Re-fit the small plastic cover piece.

Cover torque setting: 11 ÷ 13 N·m
Driven pulley shaft nut torque setting:
54 ÷ 60 N·m

56

ENGINE - DRIVE

Disassembling the brake shoes

- Withdraw the rear brake shoes by twis­ting one of the pair as shown in the figu­re.

N.B.: When this operation is carried out

with the brake still assembled in the
machine, it is first necessary to remove
the silencer and the rear wheel.

Disassembling the rear brake lever and
operating arm

- Remove the screw as shown in the figu­re, and then withdraw the operating arm.

N.B.: In order to ensure easy removal

of the operating arm, do not turn it while
disassembling.

Rear hub

- Drain the oil from the rear hub after
removing the oil drain plug as shown in
the figure.

- Withdraw the brake shoes and their
washers

- Remove the 7 securing screws and
washers shown in the figure.

- Withdraw the hub cover and gasket.

Disassembly of the wheel shaft

- Remove the wheel shaft with the gea­ring complete with the intermediate
gears.

57

ENGINE - DRIVE

Hub case bearings

- Check the condition of the bearings in
the hub case (for wear, play and noise).
In the event that any faults are discove­red, proceed as described below.

- In order to strip the three 15 mm bea­rings, 2 on the crankcase and 2 on the
hub cover, use the special extractor tool
(part number 19.1 21467/13/9).

Dis-assembly of the wheel shaft
bearings in the hub cover

- Remove the Seeger ring from the outsi­de of the hub cover.

- Extract the bearing using the appropria­te tools (part numbers 19.1.20376-

19.1.20364-19.1.20375). Be careful to
support the hub cover properly, as
shown in the figure.

- Withdraw the oil seal using the special
extractor tools (part numbers

19.1.20376-19.1.20359), as shown in
the figure.

Stripping the driven pulley shaft

- In order to carry out the dis-assembly of
the driven pulley shaft, the bearing and
the oil seal, first remove the drive cover
and the clutch assembly, as has been
described above.

- Withdraw the driven pulley shaft from
the bearing.

- Extract the oil seal, working from the
inside of the bearing, and taking great
care not to damage the oil seal seating,
and forcing it out on the drive side.

- Extract the Seeger ring as shown in the
figure.

- Extract the driven pulley shaft bearing
using the special punch (part number

19.1.20376-19.1.20363-19.1.20375).

58

ENGINE - DRIVE

Assembling the hub cover bearings

- In order to assemble the hub cover bea­rings it is first necessary to heat up the
parts using the recommended heat gun
(part numbers 19.1.20150 – 19.1.20151)

- The three 15 mm bearings should be fit­ted using the special tools (part num­bers 19.1.20412-19.1.20359)

N.B.: In vehicles with a close pitch,

these bearings should be placed in the
seatings as shown in the figure.

Assembling the driven pulley shaft
bearing

- Heat up the parts using the special heat
gun (part numbers 19.1.20150
–19.1.20151).

- Reassemble the driven pulley shaft bea­ring using the special tools (part num­bers 19.1.20376-363-359), and positio­ning it so that the ball-bearings can be
seen on the inside face of the hub.

- Re-fit the Seeger ring fitting the opening
away from the bearing as shown in the
figure, and the new oil seal flush with
the surface of the crankcase.

Checking the hub cover

- Check that the mating surfaces shown
no signs of warping or deformations.

- Check that the bearing seatings and the
brake operating arm seatings are in
sound condition.

- In the event of locating any faults, repla­ce the hub cover.

Assembling the wheel shaft bearing

- Heat up the parts using the special heat
gun (part numbers 19.1.20150 -

19.1.20151).

- The wheel shaft bearing mounted in the
hub cover should be fitted using the
special tools (part numbers 19.1.20364-

19.1.20360- 19.1.20376).

- Fit the Seeger ring.

- Fit the oil seal flush with the inner surfa­ce of the hub cover as shown in the figu­re, using the appropriate special tools
(part numbers 19.1.20376-19.1.20360),
and with the sealing lip facing into the
interior of the hub.

59

ENGINE - DRIVE

Checking the hub shafts

- Check that the three shafts show no
signs of wear or deformations in the sur­face with gear teeth, in the bearing sea­tings, and in the oil seal seatings.

- In the event of finding any faults, replace
the defective parts.

Assembling the hub gears

- In the case of vehicles with close pitch,
fit the three shafts as shown in the figu­re.

Assembling the hub cover

- Fit a new gasket aligning over the cen­tring pins.

- Fit the cover, taking care to align the
pressure relief tube correctly.

- Tighten the 7 securing screws to the
recommended torque setting, locating
the tube support clip in the position
shown in the figure.

Torque setting: 24 ÷ 27 N·m

Assembling the rear brake
operating arm

- Check that the rear brake operating arm
and rear brake shaft show no signs of
wear.

- If any defects are found, replace the
operating arm.

- Fit the 2 O-rings, lubricating them with
AGIP grease.

- Fit the operating arm and the lever onto
the engine crankcase, taking care that
to align the two profiles with the double­toothed gear shown in the figure.

- Tighten the securing screw to the
recommended torque setting

Torque setting: 11 ÷ 13 N·m.

60

ENGINE - DRIVE

Assembling the brake shoes

- Check that the thickness of the friction
material is grater than the minimum spe­cified.
Minimum allowed thickness: 1 mm.

- Check that there are no signs of wear at
the operating arm support points, or on
the pivot stud.

- Check that the springs show no signs of
wear or damage.

- In the event that defects are found,
replace the brake shoes.

- Fit the brake shoes with the springs in
the reverse order to assembly.

N.B.: If noise is detected in the rear

brake, check that the shoes are correctly
situated on the pivot stud. For the same
reason, the springs should take on a cur­ved shape, resting on the supports loca­ted on the hub cover.

Dis-assembling the fan cover deflector

- After first removing the 4 securing
screws, remove the deflector.

– When withdrawing the
deflector, remove the connector from its
housing on the deflector.

Dis-assembling the cooling fan

- Remove the cooling fan after first

undoing the 3 securing screws as
shown in the figure.

Caution

61

ENGINE - DRIVE

ENGINE - MAGNETO

Dis-assembling magneto

- Block the magneto from rotating by
means of the compass spanner (part
number 19.1.20565).

- Withdraw the nut.

- Using a different compass
spanner than the one which forms part of
the basic tool kit may cause damage to
the stator coils.

- Withdraw the magneto using the special

extractor tool (part number 19.1.48564).

Stripping the stator

- Remove the electrical terminal on the

minimum oil pressure bulb.

- Remove the 2 pick-up securing screws,

the cable restraint strap securing screw,
and the 2 stator securing screws as
shown in the figure.

- Withdraw the stator and wiring.

Checking the stator

- Use a tester to check for continuity

(approx. 1) between connections 5-3
and 5-1.

- Check earth insulation over the three

stator phases, 5-earth, 3-earth, 1-earth.
Minimum resistance: 740 ± 10 m.

Checking the oil pressure bulb

- Use a tester to check for continuity bet-

ween connection 4 and earth (with the
engine stopped).

Caution

62

ENGINE - MAGNETO

Checking the Pick-Up

- Check that there is a resistance reading
of approximately 105 ÷ 124 at 20ºC bet­ween connections 4 and earth.

- If different readings from those indicated
are found, replace the faulty parts.

N.B.: The values indicated are based

on ambient temperature. Checking the
stator at operating temperatures will give
reading higher than those indicated.

Checking the magneto

- Check the integrity of the internal plastic
elements in the magneto and the Pick­Up operating plate.

Assembling the Stator assembly

- Re-assemble the stator and the magne­to in reverse order to stripping, taking
care to tighten the securing screws to
the recommended torque settings.

- Refit the cabling as shown in the figure.

N.B.: The Pick-Up cable should be pla-

ced between the upper securing screw
and the reference stud, as shown in the
detail view.

Assembling the magneto

- Fit the magneto taking care to ensure
that the key is inserted correctly.

- Lock the magneto nut to the torque set­ting recommended.

Torque setting: 52 ÷ 58 N·m.

- Check that the Pick-up gap falls betwe­en 0.34 ÷ 0.76 mm.

- When assembling the Pick-Up there is
not expected to be adjustment of the
gap.

- Different readings are caused by defor­mations occurring in the Pick-Up sup­port.

N.B.: Variations in the magneto gap will

cause changes in the minimum output
engine speed of the ignition system.

63

ENGINE - MAGNETO

Assembling the fan cover and the mag­neto deflector

- Remount the parts in the reverse order
from disassembly.

- Take care to ensure that
the magneto connector is correctly loca­ted.

- Ensure that the distance pieces are pre­sent on the 2 rear deflector securing
screws.

- The long distance piece should be fitted
at the top.

Caution

64

ENGINE - MAGNETO

ENGINE - LUBRICATION

Checking the oil pressure

- After removing the fan cover deflector
as described in the chapter “The
Magneto”, disconnect the electrical ter­minal of the minimum oil pressure bulb
and extract the bulb.

- With the engine running at idle, 1650
rpm, and the engine oil at a temperature
of approximately 90ºC, check that the oil
pressure reading lies between 0.5 and

1.2 atmospheres.

- With the engine running at 6,000 rpm,
and the oil temperature at approximately
90ºC, check that the oil pressure falls
between 3.2 and 4.2 atmospheres.

- After completing the check, withdraw the
specific testing tools mounted on the
engine, refit the oil pressure bulb and
lock it to the torque setting prescribed,
and fit the fan cover deflector.

- If non-standard oil pressure readings
are recorded, move on to check, in this
order, the oil filter, the bypass, the oil
pump, and the seatings over the engine
shaft.

N.B.: the check should be carried out

with the engine oil exactly at the correct
level, and with the oil filter in good condi­tion.

Minimum oil pressure allowed:

3.2 atmospheres.
Torque setting: 12 ÷ 14 N·m.

(Valid also for the connector of control)

Disassembling the oil sump oil
pressure regulating by-pass

- Remove the oil filler cap, the drive cover
the drive pulley assembly complete with
the drive belt and the gear wheel, as
described in Chap 3 “The Drive”.

- Drain the oil from the sump as has been
described above.

- Remove the 7 securing screws as
shown in the figure together with the 2
securing clips attaching the drive to the
rear brake.

65

ENGINE - LUBRICATION

- Remove the spring, the by-pass piston
and the gasket as shown in the second
figure.

Checking the By-pass

- Check the free length of the spring.
Standard length: 54.2 mm

- Check that the piston does not show
any signs of scoring.

- Ensure that the piston can move freely
over the crankcase, and that a suffi­ciently good seal is maintained.

- If the piston is either scored or does not
move freely, clean off any dirt or replace
with new parts.

Checking the oil pump

- Remove the chain housing cover by
releasing the 3 securing screws, as
shown in the figure, together with the
copper washers.

- Extract the cover using the appropriate
lugs.

N.B.: In order to avoid the lugs brea-

king, pull out with a movement parallel to
the line of the engine shaft.

- Remove the small oil pump drive pulley
cover after removing the two securing
scores as shown in the figure.

- Immobilise the oil pump drive pulley,
using a screwdriver inserted in the hole
provided for that purpose.

66

ENGINE - LUBRICATION

- Remove the central securing screw with
the hollow washer as shown in the figu­re.

- Remove the chain complete with the
pulley.

- Remove the engine shaft drive pinion.

- Remove the oil pump after unscrewing
the two securing screws shown in the
figure.

- Remove the sealing gasket.

N.B.: It is advisable to mark the chain

to ensure that it will be maintained in the
same direction of rotation.

Checking the oil pump

- Remove the two securing screws and
the small oil pump cover.

- Remove the internal rotor spring was­her.

- Remove the rotors and then carry out a
thorough wash using petrol and com­pressed air.

- Refit the two rotors onto the pump body
while keeping in view the 2 reference
points as shown in the second figure.
Assemble locking ring,

- Check the distance between the rotors
in the position shown in the figure using
feeler gauges.

Maximum play allowed: 0.12 mm

- Check the distance between the exter­nal rotor and the pump body, see figure.

Maximum play allowed: 0.20 mm

67

ENGINE - LUBRICATION

- Check the axial play between the rotors
using a straight edge as a reference
plane as shown in the figure.

Upper permissible limit: 0.09 mm

Assembling the oil pump

- Check that there are no signs of wear
on the pump shaft and body.

- Check that the pump cover show no
signs of wear or scratching.

- If incorrect readings are found, or scrat­ching, replace the defective parts or the
entire assembly.

- Fit the pulley onto the pump, the central
securing screw to the torque specified,
and the bend-up washer.

Torque setting: 12 ÷ 14 N·m

N.B.: Fit the bend-up washer on the

outer perimeter and in contact with the
pulley.

- Fit the small cover on the pump and
tighten the two securing screws to the
recommended torque setting.

Torque setting: 0.7 ÷ 0-9 N·m

Chain cover

- Check that there are no signs of wear in
the tensioner slider.

- Where damage is found, replace the
part or mount it the other way around,
so that the other side will be subject to
wear.

68

ENGINE - LUBRICATION

- Remove the oil seal using the special
tools (part number 19.1.20376-

19.1.20357).

- Fit a new oil seal using the special tools
(19.1.20376-19.1.20359), flush with the
outer surface.

- Fit a new O-ring and grease it tho­roughly, using grease.

- Fit the cover over the engine crankcase,
set the three securing screws with cop­per washers, and fit the cover into its
seating, tightening the three securing
screws.

- Block the 3 securing screws to the
required torque.

Torque setting: 4 ÷ 5 N·m.

Assembling the by-pass and the
oil manifold pump

- Re-fit the by-pass piston in its seating.

- Insert the adjuster spring.

- Fit a new oil sump gasket.

- Offer up the sump taking care to insert
the spring in the extension located on
the collector Itself.

- Fit the securing screws again and the
rear brake drive support clips in the
reverse order from dis-assembly.

- Tighten up the securing screws to the
recommended torque setting.

Torque setting: 11 ÷ 13 N·m

- Reassemble the drive pulley assembly,
the belt, the gears, and the transmission
cover, as described in the Chapter on
Transmissions.

- For the checks corresponding to
lubrication problems in the rocker
link articulation, please refer to the
Chapter “Crankcase and Engine
Shaft”.

69

ENGINE - LUBRICATION

Dis-assembling the cooling
system deflectors

- Remove the magneto cover deflector
and the fan; please refer to Chapter
“Magneto”.

- Remove the tappet cover together with
the decanter cover; please refer to
Chapter “General and Maintenance
Information”.

- Slacken off the clamp and take the car­burettor off the manifold.

- Remove the two securing screws as
shown in the figure and withdraw the
manifold.

- Withdraw the two self-tapping screws
and the securing screw on the side of
the crankcase.

- Remove the two deflectors and the
spark-plug seat cover.

- Remove the deflector to crankcase sea­ling gasket.

Dis-assembling the timing drive

- Remove the part listed as follows: drive
cover, drive pulley and drive belt, starter
pinion, oil sump and spring and By-pass
piston, oil pump pulley cap, O-Ring on
engine shaft, and the pinion distance
washer.

- Remove the tappet cover.

- Extract the central screw and washer
from the tappet weight retaining hub as
shown in the figure.

- Remove the automatic tappet weight
return spring, the tappet weight and stop
washer.

- First slacken off the central tensioner
securing screw.

- Remove the two securing screws as
shown in the figure.

70

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

- Remove the internal hex head screws
and the counterweight as shown in the
figure.

- Remove the camshaft drive pulley and
the washer.

- Withdraw the timing drive pinion from
the engine shaft.

- Remove the screw as shown in the figu­re, the distance piece and the tensioner
as shown in the figure.

N.B.: It is recommended to matchmark

the chain to assure maintenance of the
direction of rotation. In order to remove
the tensioner shoe, it is necessary to work
from the transmission side. The chain
guide shoe can only be removed after
disassembling the cylinder head.

Dis-assembling the camshaft and the
rockers

- Remove the two camshaft securing
screws and clamp as shown in the figu­re.

71

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

- Remove the camshaft.

- Remove the rocker shaft working from
the hole on the magneto side.

- Remove the rockers and the spring was­her.

N.B.: Matchmark the assembly position

of the rockers in order to avoid inverting
the operation of inlet and exhaust.

Dis-assembling the cylinder head

- Remove the spark-plug.

- Remove the 2 side securing screws as
shown in the figure.

- Slacken off the 4 cylinder head-cylinder
securing nuts in two or three rotations
around the nuts following a cross pat­tern.

- Withdraw the cylinder head, the 2 cen­tring pins and the gasket.

N.B.: If necessary, the cylinder head

may be removed with the camshaft, roc­ker shaft and securing pin. The cylinder
head may also be removed without with­drawing the chain or chain tensioner.

Dis-assembling the valves

- Use the special tool (part number

19.1.20382/11) fitted with the part
shown in the figure to move on to remo­ve the semi-cones, the spring plates,
and the two valves.

72

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

- Remove the oil seal using the appropria­te special too (part number 19.1 20431).

- Remove the lower spring supports.

Dis-assembling the cylinder
and the piston

- Remove the chain guide shoe.

- Remove the cylinder base gasket.

- in order to avoid damaging
the piston, support it properly while dis­assembling the cylinder.

- Remove the 2 locking rings, the gudge-

on pin, and the piston.

- Remove the piston rings from the piston.

N.B.: Take particular care not to dama-

ge the piston rings when dis-assembling
them from the piston.

Checking the connecting rod little end.

- Use a internal micrometer measure the

internal diameter of the little end.
Standard diameter: 15 mm.
Maximum permitted diameter: 15.030 mm.

N.B.: When the diameter of the con-

necting rod little end is greater than the
maximum permitted diameter, or if it
shows signs of wear or localised heating,
replace the engine shaft as described in
the Chapter “Crankcase and Engine
Shaft”.

Caution

73

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

+0,015
+0,025

Gudgeon pin diameter

- Check the outside diameter of the gud­geon pin.

Standard diameter: 15 mm
Minimum acceptable diameter:

14.994 mm

- Calculate the play arising from matching
the gudgeon pin to the piston.

Standard play: 0.001 ÷ 0.010 mm

N.B.: The gudgeon pin seatings are fit-

ted with two lubrication channels: for this
reason, the diameter should be measured
in the direction parallel to the axis of the
piston.

- Measure the external diameter of the
piston following a direction square to the
gudgeon pin axis.

- The measurement should be made at a
depth of 36.5 mm from the crown of the
piston, as is shown in the figure.

N.B.: The gudgeon pin seatings are fit-

ted with two lubrication channels: for this
reason, the diameter should be measured
in the direction parallel to the axis of the
piston.

- Use an interior micrometer to measure
the internal dimensions of the cylinder
following the directions shown in the
figure, and at three different depths.

- Check that the mating surface with the
cylinder head shows no signs of wear or
deformation.

Maximum permitted out of true:

0.05 mm

- The pistons and cylinders are classified
into categories according to their diame­ters. Matching is carried out with similar
categories as follows: A-A, B-B, C-C,
D-D.

74

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

Vehicle Servicing Data 125 cc. 57 x 48,6 4T

Assembly Clearance

Mating classes

75

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

PART

Cylinder

Piston, cast pockets

Piston, finished pockets

Cylinder, 1st oversize

Pistón 1st oversize

Cylinder, 2n oversize

Pistón 2n oversize

Cylinder, 3rd oversize

Pistón 3rd oversize

Dimensions

57

+0,025

56,959

+0,014

57,2

+0,025

57,159

+0,014

57,4

+0,025

57,359

+0,014

57,6

+0,025

57,559

+0,014

Class

A
B
C

D
A1
B1
C1
D1
A2
B2
C2
D2
A3
B3
C3
D3

Cylinder
56,997 ÷ 57,004
57,004 ÷ 57,011
57,011 ÷ 57,018
57,018 ÷ 57,025
57,197 ÷ 57,204
57,204 ÷ 57,211
57,211 ÷ 57,218
57,218 ÷ 57,225
57,397 ÷ 57,404
57,404 ÷ 57,411
57,411 ÷ 57,418
57,418 ÷ 57,425
57,597 ÷ 57,604
57,604 ÷ 57,611
57,611 ÷ 57,618
57,618 ÷ 57,625

PISTÓN
56,945 ÷ 56,952
56,952 ÷ 56,959
56,959 ÷ 56,966
56,966 ÷ 56,973
57,145 ÷ 57,152
57,152 ÷ 57,159
57,159 ÷ 57,166
57,166 ÷ 57,173
57,345 ÷ 57,352
57,352 ÷ 57,359
57,359 ÷ 57,366
57,366 ÷ 57,373
57,545 ÷ 57,552
57,552 ÷ 57,559
57,559 ÷ 57,566
57,566 ÷ 57,573

Mating classes

ASSEMBLY

CLEARANCES

0,045
0,059

Value in mm.

76

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

DESIGNATION

1st oil seal piston rings

2nd oil seal piston rings

3rd oil seal piston rings

Compresion ring 1st oversize

Oil scraper ring 1st oversize
Oil scraper ring 1st oversize

Compresion ring 2nd oversize

Oil scraper ring 2nd oversize
Oil scraper ring 2nd oversize

Compresion ring 3rd oversize

Oil scraper ring 3rd oversize
Oil scraper ring 3rd oversize

DIMENSIONS

57 x 1

57 x 1
57 x 2,5
57,2 x 1
57,2 x 1

57,2 x 2,5

57,4 x 1
57,4 x 1

57,4 x 2,5

57,6 x 1
57,6 x 1

57,6 x 2,4

CATEGORY

DESIGNATION

A
A
A
A
A
A
A
A
A
A
A
A

ASSEMBLY

CLEARANCES

0,20 ÷ 0,40
0,10 ÷ 0,30
0,15 ÷ 0,35
0,20 ÷ 0,40
0,10 ÷ 0,30
0,15 ÷ 0,35
0,20 ÷ 0,40
0,10 ÷ 0,30
0,15 ÷ 0,35
0,20 ÷ 0,40
0,10 ÷ 0,30
0,15 ÷ 0,35

Vehicle Servicing Data 125 cc. 57 x 48,6 4T

Oversize table

SYSTEM OF THICKNESSES TO MAINTAIN THE COMPRESSION RATIO

RC = 10,4 ÷ 11,2

- Calculate the difference between the two measure­ments, using the table shown on the right. Identify
the thickness of the cylinder base gasket to be used
in re-assembly. The correct identification of the
cylinder base gasket will give the correct compres­sion ratio.

- Withdraw the special tool and the cylinder.

Standard Compression Ratio (CR): 10.6 ± 0.5

Measured dimension

Cylinder base gasket

(mm) thickness (mm)

1 ÷ 1,1 0,8 ± 0,05
1,1 ÷ 1,3 0,6 ± 0,05
1,3 ÷ 1,4 0,4 ± 0,05

Value in mm.

Vehicle Servicing Data 150 cc. 62,6 x 48,6 4T

Assemble clearances

Mating classes

77

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

PART

Cylinder

Ø C

Piston

Ø P

Cylinder 1st oversize

Ø C

Piston 1st oversize

Ø P

Cylinder 2nd oversize

Ø C

Piston 2nd oversize

Ø P

Cylinder 3rd oversize

Ø C

Piston 3rd oversize

Ø P

Dimensions

62,6

+0,008

-0,020

62,547 ±0,014

62,8

+0,008

-0,020

62,747 ±0,014

63,0

+0,008

-0,020

62,947 ±0,014

63,2

-0,008

-0,020

63,147 ±0,014

Class

A
B
C

D
A1
B1
C1
D1
A2
B2
C2
D2
A3
B3
C3
D3

Cylinder
62,580 ÷ 62,587
62,587 ÷ 62,594
62,594 ÷ 62,601
62,601 ÷ 62,608
62,780 ÷ 62,787
62,787 ÷ 62,794
62,794 ÷ 62,801
62,801 ÷ 62,808
62,980 ÷ 62,987
62,987 ÷ 62,994
62,994 ÷ 63,001
63,001 ÷ 63,008
63,180 ÷ 63,187
63,187 ÷ 63,194
63,194 ÷ 63,201
63,201 ÷ 63,208

Piston
62,533 ÷ 62,540
62,540 ÷ 62,547
62,547 ÷ 62,554
62,554 ÷ 62,561
62,733 ÷ 62,740
62,740 ÷ 62,747
62,747 ÷ 62,754
62,754 ÷ 62,761
62,933 ÷ 62,940
62,940 ÷ 62,947
62,947 ÷ 62,954
62,954 ÷ 62,961
63,133 ÷ 63,140
63,140 ÷ 63,147
63,147 ÷ 63,154
63,154 ÷ 63,161

Mating classes ASSEMBLY

CLEARANCES

0,040

÷

0,054

Value in mm.

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

VEHICLE SERVICING DATA 150 CC. 62,6 X 48,6 4T

Oversize table

DESIGNATION

1st oil seal piston rings

2nd oil seal piston rings

3rd oil seal piston rings

Compresion ring 1st oversize

Oil scraper ring 1st oversize

Oil scraper ring 1st oversize

Compresion ring 2nd oversize

Oil scraper ring 2nd oversize

Oil scraper ring 2nd oversize

Compresion ring 3rd oversize

Oil scraper ring 3rd oversize

Oil scraper ring 3rd oversize

DIMENSIONS

62,6 x 1

62,6 x 1

62,6 x 2,5

62,8 x 1

62,8 x 1

62,8 x 2,5

63,0 x 1

63,0 x 1

63,0 x 2,5

63,2 x 1

63,2 x 1

63,2 x 2,5

CATEGORY

DESIGNATION

A

A

A

A

A

A

A

A

A

A

A

A

Value in mm

ASSEMBLY

CLEARANCES

0,15 ÷ 0,30

0,20 ÷ 0,40

0,20 ÷ 0,40

0,15 ÷ 0,30

0,20 ÷ 0,40

0,20 ÷ 0,40

0,15 ÷ 0,30

0,20 ÷ 0,40

0,20 ÷ 0,40

0,15 ÷ 0,30

0,20 ÷ 0,40

0,20 ÷ 0,40

CYLINDER - PISTON ASSY

Categories coupling 200

NAME

Cylinder

Cylinder

Piston

Piston

PLAY

72 + 0,018 - 0,010

72 + 0,018 - 0,010

71,967 ± 0,014

71,967 ± 0,014

INITIALS

B

A

D

C

CYLINDER

71,997 + 72,004

71,990 + 71,997

72,011 + 72,018

72,004 + 72,011

PISTON

71,960 + 71,967

71,953 + 71,960

71,974 + 71,981

71,967 + 71,974

PLAY ON FITTING

0,030 - 0,044

0,030 - 0,044

0,030 - 0,044

0,030 - 0,044

78

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

The lenght <A> to be measured refers to the pieston protrusion. It indicates the amount by which the surface formed by the
piston crown tops the surface formed by the upper part of the cylinder. The more the piston descends into the cylinder, the
less the base gasket to be applied (to recover the compression ratio) will be and vice versa.

Note

The measurement of
and the cylinder, and after resetting the comparator, complete with support, on a rectified surface.

<A>, must be carried with the piston at the TDC, without any gasket installed between the crankcase

125 cc VERSION WITH METALLIC HEAD GASKET (0,3)

NAME

Thicknesses 125

Thicknesses 125

1,40 ÷ 1,65

1,65 ÷ 1,90

Characteristic

Compression ratio - 200cc version

Rc: 11 ÷ 12:1

200 cc VERSION WITH METALLIC HEAD GASKET (0,3)

NAME

Thicknesses 200

Thicknesses 200

Thicknesses 200

2,50 ÷ 2,40

2,40 ÷ 2,20

2,20 ÷ 2,10

Characteristic

Compression ratio - 125cc version

Rc: 11,50 ÷ 13:1

THICKNESSMEASURE A

0,4 ± 0,05

0,6 ± 0,05

THICKNESSMEASURE A

0,4 ± 0,05

0,6 ± 0,05

0,8 ± 0,05

OVERSIZE 200CC ENGINE

NAME

Scraper ring lining

Scraper ring lining

Compression lining

DENOMINATION

DIMENSIONS

72 x 2,5

72 x 1

72 x 1,5

INITIALS

A

A

A

QUANTITY

0,20 ÷ 0,40

0,20 ÷ 0,40

0,15 ÷ 030

78

- The cylinder should be re-bored in such
a way as to ensure that the finish obser­ves the original angulation.

- The cylinder surface should present a
roughness of 0.9 microns

- This is indispensable in order to ensure
correct fit of the oil seals, and in this way
guarantee minimum oil consumption
and optimum performance.

- Oversize pistons are available to match
the cylinder, subdivided into three clas­ses 1st, 2nd, and 3rd, corresponding to

0.2, 0.4 and 0.6 mm oversizes. The
oversizes are in turn divided into four
classes: A-A, B-B, C-C, and D-D.

Piston

- Take care to clean the grooves for the
oil seal piston rings very carefully.

- Using appropriate feeler gauges, mea­sure the mating clearance between the
oil seal piston rings and the piston groo­ves, as shown in the figure.

- If clearances are found to be greater
than those indicated in the table, replace
the piston.

Oil seal rings

- Insert the pistons rings one by one into
the cylinder, in the area where it is still
the original diameter. The rings should
be inserted perpendicular to the bore,
using the piston to push them down.

- Measure the gap at the ends of the pis­ton rings, as shown in the figure, using
feeler gauges.

- If the measured gaps are higher than
those shown in the table, the piston
rings should be replaced.

79

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

Normal clearance (mm) Wear limit: max. clearance

Top ring 0,025 ÷ 0,070 0,080
Middle ring 0,015 ÷ 0,060 0,070
Oil scraper ring 0,015÷ 0,060 0,070

N.B.: Before proceeding to replace the

piston rings, take care to observe the spe­cifications relating to the match between
the piston rings and the piston grooves,
and between the piston and the cylinder.
It should be borne in mind that fitting new
piston rings into a used cylinder may give
rise to conditions where the fit is different
from the normal values.

Fitting the piston

- Fit the piston, with the gudgeon pin,
over the connecting rod, taking care to
align the piston so that the arrow faces
the exhaust port.

- Insert the gudgeon pin locking ring using
the special tool (part number

19.1.20.430).

- With the locking ring gap in the position
indicated in the tool, insert the locking
ring into position with the punch.

- Then fit the gudgeon pin seal using the
punch as shown in the figure.

N.B.: The tool for fitting the locking

rings should be employed using hand
pressure only.

- Using a hammer may

cause damage to the ring seatings.

Checking the piston for concavity

- Fit the cylinder provisionally over the
piston, without using a gasket at the
cylinder base.

- Mount a comparator onto the special
tool (part number 19.1.20428).

- Set the comparator to zero using a refe­rence plane, using a preset load, for
example, of 5 mm. Keeping this zero
position, place the tool. Over the cylin­der, and secure it using the two securing
screws as shown in the figure.

- Turn the engine shaft until it reaches
TDC (the point at which the comparator
reverses its direction of rotation).

Caution

80

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

Normal gap

maximum gap
Top ring 0,15÷ 0,30 0,40
Middle ring 0,20 ÷ 0,40 0,50
Oil scraper ring 0,20 ÷ 0,40 0,50

- Calculate the difference between the
two measured readings: and using the
table shown at the right, identify which
cylinder base gasket should be used for
re-assembly. Correct identification of the
thickness of the cylinder base gasket
will give the correct compression ratio.

- Withdraw the special tool from the cylin­der.

Normal compression ratio:
CR = 10.6 ± 0.5

Fitting the oil-seal piston rings

- Fit the oil seal piston ring spring over the
piston.

- Fit the oil seal piston ring, keeping the
gap on the side opposite to the gap in
the spring, and the wording “TOP”
facing up towards the crown of the pis­ton. The manufactured step must in all
circumstances be fitted so as to face up
towards the crown of the piston.

- Fit the 2nd piston ring, the oil seal ring,
with its identification letter or the words
“TOP” facing up towards the piston
crown. The manufactured step must in
all circumstances be fitted so as to face
down away from the crown of the piston.

- Fit the 3rd piston ring, the oil seal ring,
with its identification letter or the wor­ding “TOP” facing up towards the piston
crown.

N.B.: In order to achieve a closer fit

with the two oil seal piston rings, they are
manufactured with the surface in contact
with the cylinder of a conical section.

- Fit the piston rings with the gaps out of
phase by 120º as shown in the figure.

- Lubricate the parts with engine oil.

Fitting the cylinder

- Offer up the new cylinder base gasket,
chosen with the thickness as determi­ned above.

- Using the special fork tool (part number

19.1.20426) and the piston ring com­pressor (part number 19.1.20427),
assemble the cylinder over the piston as
shown in the figure.

N.B.: Before fitting the cylinder, care-

fully blow out the oil ways and grease the
cylinder lining.

81

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

Measured Base Gasket

dimensions (mm) thickness (mm)

1 ÷ 1,1 0,8 ± 0,05
1,1 ÷ 1,3 0,6 ± 0,05
1,3 ÷ 1,4 0,4 ± 0,05

150 cc.

Checking the cylinder head

- Use a straight edge to check that the flat
mating surface of the cylinder head
shows no signs of wear or unevenness.

Maximum out of true: 0.05 mm

- Check that the camshaft seatings and
the rocker shaft seatings show no signs
of wear.

- Check that there is no wear on the
mating surface for the cylinder head
cover, the inlet manifold, of the exhaust
manifold.

Checking the seating of the valves

- Measure the width of the sealing surface
with the valve seats.

Sealing surface width
Inlet: 3.1 mm
Exhaust: 3 mm

Checking the valve seats

- Clean the valves guides of any carbon
deposits.

- Measure the internal diameter of each
valve guise.

- Carry out the measurements in accor­dance with the direction of the rocker
force, and at three different depths.

Exhaust valve guide

Normal diameter: 5.022 mm

Inlet valve guide

- Normal diameter: 5.022 mm

82

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

Normal Diameter (mm)
A Ø 12 ÷ 12,018
B Ø 20 ÷ 20,021
C Ø 32,5 ÷ 32,525

- In the event that the readings of the width of the valve sea­ting on the valve seat surface, or the diameter of the valve
guide exceed the specified values, replace the cylinder
head. Check the width of the seating surface on the valve
seat “V”: maximum limit of wear: 1.6 mm

Checking the valves

- Check the diameter of the valve stem at
the three points as shown in the figure.

Minimum permitted diameter

Inlet: 4.96 mm
Exhaust: 4.95 mm

- Calculate the play between the valve
and the valve guide.

Normal play:

Inlet: 0.013 ÷ 0.040 mm
Exhaust: 0.025 ÷ 0.052 mm

Maximum permitted play:
Inlet: 0.062 mm
Exhaust: 0.072 mm

- Check that there is no wear on the con­tact surface of the articulated adjust­ment point.

Normal length of the valve

Inlet: 80.6 mm
Exhaust: 79.6 mm

- If the sealing surface of the valve is
measured to be greater that the speci­fied limit, has a non-continuous surface
in one or more points, or is clearly cur­ved, replace the valve.

- If the checks carried out as described
above show no signs of defects in the
valves, the same ones may be used
again. In order to achieve better sealing
characteristics, it is recommended to
grind the valves. This should be done
working carefully and using fine grain
grinding paste. While grinding the val­ves, support the cylinder head with the
axis of the valves in a horizontal posi­tion, so as to avoid deposits of grinding
paste entering into the valve guide –
valve stem contact area (see the figure).

- in order to avoid scratching
the contact surface, do not continue to
rotate the valve once the grinding paste
has been used up. Wash the cylinder
head and the valves very carefully using a
product appropriate for the type of grin­ding paste used.

Caution

83

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

Testing the valve seat seal

- Insert the valves into the cylinder head.

- Test the two valves in turn.

- The test is carried out by filling the mani­fold with petrol, and checking whether
the petrol seeps out past the valve while
holding it shut with a finger.

Checking the spring, bearing plates
and semi-cones

- Check that the upper spring bearing pla­tes and the semi-cones show no signs
of defects.

Assembling the valves

- Lubricate the valves guides using engi­ne oil.

- Insert the valve spring bearer plates into
the cylinder head.

- Using the special punch tool (part num­ber 19.1.20306) insert the two retaining
rings in turn.

- Insert the valves, the valve springs, and
the valve spring bearer plates. Using
the special tool (part number

19.1.20382/11), with part no. 11 fitted,
compress the valve springs and insert
the semi-cones into their seatings.

84

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

Checking the timing components

- Check that the guide shoe and the ten­sioner shoe are not excessively worn.

- Verify that there are no signs of wear in
the chain, camshaft drive pulley and
pinion assembly.

- If signs of wear are found, replace the
parts, or if the chain, the pinion or the
pulley are worn, replace the whole
assembly.

- Remove the central securing screw and
washer, and the tensioner spring. Check
that there are no signs of wear in the
one-way system.

- Check that the tensioner spring is in
good working condition.

- If signs of wear are found, replace the
entire assembly.

Checking the camshaft

- Check that there are no signs of wear or
scratching on the camshaft bearing sur­faces.

Normal diameter

Diameter surface A:
Ø 32.5 +0.025 -0.041 mm
Diameter surface B:
Ø 20 +0.020 -0.033 mm

Minimum permissible diameter

Diameter surface Ø A: 32.440 mm
Diameter surface Ø B: 19.950 mm

Normal height

Inlet: 27.8 mm
Exhaust: 27.8 mm

- Check that there are no signs of wear or
scratching on the cams.

Maximum permissible axial play: 0.42 mm

- If any signs of wear, or measurements
different from those specified are found,
replace the defective parts.

85

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

- Check that there are no signs of wear in
the automatic tappet cam, in the stop
roller, or in the rubber stop on the res­training hub.

- Check that the tappet spring is not out of
shape.

- If wear is found, replace the faulty parts.

- Check that the rocker shaft show no
signs of wear or scratching.

Minimum permissible diameter:
Ø 11.970 mm diam.

- Check the internal bore diameter of
each rocker.

Maximum permissible diameter:
Ø 12.030 mm diam.

- Check that there are no signs of wear
on the cam contact shoe or on the arti­culated adjustment plate.

- Check that the are no signs of wear on
the spring washer controlling the axial
play of the rockers. If any signs of defect
are found, replace the damaged parts.

Assembling the cylinder head and
timing components

- Insert the timing chain guide shoe.
Insert the cylinder head – cylinder cen­tring the pins. Place the cylinder head
gasket on the cylinder and offer up the
cylinder head.

- Tighten up the nuts and lock them in
sequence up to the recommended tor­que setting in 2 or 3 rotations in a cross
pattern.

Torque setting: 28 ÷ 20 N·m

- Fit the two timing chain side securing
screws and lock them to the recommen­ded torque setting.

Torque setting: 11 ÷ 13 N·m

N.B.: Before assembling the cylinder

head take care to ensure that the oil way
is perfectly clean, by blowing it through
with a jet of compressed air.

86

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

Assembling the cylinder head and the
timing components

- Fit the timing chain drive pinion onto the
engine shaft with the chamfer facing the
insertion side.

- Assemble the timing chain over the
engine shaft.

- Insert the tensioner shoe through the
cylinder head.

- Fit the distance piece and securing
screw.

- Fit the rocker shaft, the exhaust rocker,
the spring washer, and the inlet rocker.

- Lubricate the 2 rockers through the
upper oil holes.

- Lubricate the 2 cam shaft bearing surfa­ces and fit the camshaft to the cylinder
head with the cams away from the roc­kers.

- Assemble the retainer plate and tighten
the 2 securing screws as shown in the
figure, locking them to the recommen­ded torque setting.

Torque setting: 4 ÷ 6 N-m

- Assemble the distance piece onto the
cam shaft.

- Place the piston in the Top Dead Centre
position, using the reference marks
located on the magneto and the engine
crankcase.

- Keeping this orientation, place the
timing chain onto the camshaft drive
pulley, with the 2V timing mark aligned
with the reference point marked on the
cylinder head.

- Fit the pulley onto the camshaft.

- Assemble the counterweight with its
securing screw tightened up to the
recommended torque setting.

Torque setting.: 7 ÷ 8.5 N·m

87

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

- Insert the stop ring on the valve lifter
weight and fit the valve lifter lever over
the camshaft.

N.B.: Lubricate the stop ring with grea-

se to avoid it accidentally slipping and
falling into the interior of the engine.

- Fit the valve lifter return spring.
During this operation the spring should
be loaded to about 180º.

- Fit the retaining hub using the counter­weight securing screw as a reference
point.

- Lock the central securing screw up to
the recommended torque.

Torque setting: 12 ÷ 14 N·m

- Place the tensioner runner in its resting
position.

- Assemble the tensioner over the cylin­der using a new gasket, and lock the 2
securing screws up to the recommen­ded torque.

Torque setting: 11 ÷ 13 N·m

- Insert the spring with the central secu­ring screw and washer and lock to the
recommended torque.

Torque setting: 5 ÷ 6 N·m

- Set the valve clearance as described in
Chapter 1.

- Fit the spark plug.

Torque setting: 12 ÷ 14 N·m
Specified spark plug: Champion RG4HC
Spark plug gap: 0.8 mm

88

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

- Place the deflector sealing gasket onto
the cylinder head.

- When assembling use the timing chain
side extensions as a reference point.

- Fit the deflector securing screw to the
crankcase locking to the recommended
torque, together with the 2 self-tapping
half cover joining screws.

Torque setting: 3 ÷ 4 N·m

- Take care to ensure that the gasket
does not slip from its sealing surface
during assembly.

- Fit the spark plug access cover.

- Fit the inlet manifold, locking the 2 secu­ring screws up to the recommended tor­que.

Torque setting: 11 ÷ 13 N·m

- Offer up the carburettor to the inlet
manifold and tighten up the clamp.

N.B.: Align the carburettor correctly by

means of the extension located on the
inlet manifold.

- Reassemble the cylinder head cover,
locking the 4 securing screws up to the
recommended torque.

Torque setting: 11 ÷ 13 N·m

- Reassemble the fan and deflector.

- Reassemble the oil pump drive, the
chain seating cover, the by-pass, and
the oil sump, as described in the chapter
on the Lubrication system.

- Reassemble the drive pulley, the belt
and the drive cover as described in the
chapter on the Drive.

89

ENGINE - CYLINDER, CYLINDER HEAT AND DISTRIBUTION

- First remove the following assemblies:
drive cover, drive pulley, driven pulley
and belt, rear hub cover, gears, bea­rings, and oil seals, as described in the
chapter on the Drive.

- Remove the oil sump. The By-pass, the
chain seating cover, and the oil pump,
as described in the chapter on

Lubrication.

- Remove the magneto cover deflector,
the fan, the magneto, and the stator, as
described in the chapter on the

Magneto.

- Remove the oil filter and the oil pressure
bulb.

- Remove the cylinder-piston-cylinder
head assembly, as described in the
chapter on Cylinder, Cylinder Head,

Timing.

- Remove the 2 securing screws as
shown in the figure and the starter
motor.

- Before opening the engine crankcase
halves, it is necessary to check the axial
play on the engine shaft. In order to do
this, the special plate and support with
comparator tool (part number

19.20.262-19.1.20335).

Normal play: 0.15 ÷ 0.40 mm

Opening the engine crankcase halves

- Remove the 11 crankcase securing
screws as shown in the figure.

- Separate the crankcase halves, keeping
the engine shaft in one of the two hal­ves.

- failure to observe this advi­ce may lead to the engine shaft being
accidentally dropped.

- Remove the engine shaft.

Caution

90

ENGINE - CRAKCASE AND CRANKSHAFT

- During the crankcase half
opening and extraction of the engine shaft
operation, take care to ensure that the
threaded ends of the shaft do not strike
the block bearings. Failure to observe this
advice may lead to damage being caused
to the block bearings.

- Remove the crankcase half sealing gas-

ket.

- Remove the 2 securing screws and the

internal divider as shown in the figure.

- Remove the oil seal on the magneto

side.

- Remove the oil filter connector as

shown in the figure.

- Check the axial play on the connecting

rod big end.

Normal axial play: 0.20 ÷ 0.50 mm

- Check the radial play on the connecting

rod big end.

Normal radial play: 0.036 ÷ 0.054 mm

- Check that the retaining surfaces of the

axial play show no signs of scratching,
and use a gauge to check the width of
the engine shaft as shown in the figure.

N.B.: Take care to ensure that the

measurement is not affected by the con­necting ribs with the engine shaft bearing
surfaces.

Caution

91

ENGINE - CRAKCASE AND CRANKSHAFT

standard diameter
Cat.1 28.994 ÷ 29.000
Cat. 2 29.000 ÷ 29.006

Normal measurement: 55.75 ÷ 55-90 mm.

- The engine shaft may be
used again if the measured width lies insi­de the normal values and if the surfaces
are not scratched.

- When the engine shaft-crankcase axial

play is greater than normal, but the engi­ne shaft show no signs of any defect,
the problem is definitely caused by wear
of faulty installation in the crankcase.

- Check the diameters of both engine

shaft bearing surfaces in the axes and
planes as shown in the figure. engine
shaft-crankcase. The semi-crankshafts
are classed in two categories, Cat.1 and
Cat. 2 , as shown in the following table.

Checking crankshaft alignment

- Mount the engine shaft onto the special

support tool (part number 19.1.20074),
and measure the deviation from true
alignment at the 3 points shown in the
figure.

Maximum out of alignment: A = 0.15 mm

B = 0.01 mm
C = 0.01 mm
D = 0.10 mm

- Check the engine shaft cones, the spli-

ne seating, the oil seal seating, the
milling, and the threaded ends for good
condition.

- If any defects are found, replace the

engine shaft.

N.B.: The block bearings cannot be

adjusted. The connecting rod big end bea­rings cannot be replaced.

Caution

92

ENGINE - CRAKCASE AND CRANKSHAFT

For the same reason, the connecting
rod cannot be replaced, and during clea­ning, great care must be taken not to
allow any dirt to get into the crankshaft oil
way port.

In order to avoid causing damage to the
connecting rod bearings, do not clean the
oil ways with compressed air.

- Take care to ensure correct assembly of

the 2 shock absorbers on the handle
button.

- Incorrect assembly of the shock absor-

bers may have a serious impact on the
oil pressure in the bearings.

Checking the engine crankcase halves

- Before carrying out the checks on the

crankcase halves, it is necessary to
clean all the surfaces and oil ways tho­roughly.

- In the case of the drive side crankcase

half, pay special attention to the oil
pump seating and oil ways, the oil chan­nel and the by-pass, the block bearings,
and the drive side cooling jet, as shown
in the figure.

N.B.: The cooling jet is fed through the

block bearings. The proper operation of
this component improves the cooling of
the piston crown. If it becomes blocked,
the consequences are difficult to detect
(increased piston temperature). Failure or
loss of the jet may cause the lubrication
pressure of the block bearings and the
connecting rod bearings to fall drastically.

As has already been described in the
chapter on Lubrication, it is very important
to ensure that the by-pass seating shows
no signs of wear which may affect the
correct sealing of the lubrication pressure
regulating piston.

93

ENGINE - CRAKCASE AND CRANKSHAFT

- In the case of the magneto side crank­case half, take care with the oil ways for
the block bearings, the oil way and jet
feeding oil to the cylinder head, the
drain channel for the magneto side oil
seal.

N.B.: The cylinder head lubrication oil

way is fitted with a louvre jet so as to pro­vide the cylinder head with “low pressure”
type lubrication; this system was chosen
co as to keep the oil temperature in the oil
sump down. Any blocking of this louvre jet
will adversely affect the lubrication of the
cylinder head and the components of the
timing mechanism. Failure of the jet cau­ses a reduction of oil lubrication pressure
at the block bearings and the connecting
rod bearing.

- Check that the mating planes show no
signs of dents or deformation, and in
particular the cylinder-crankcase plane,
and the crankcase half mating surfaces.

- Any failure occurring in the crankcase
mating surface gasket or of the planes
shown in the figure may cause the loss
of oil pressure and consequently have
an adverse impact on the lubrication oil
pressure to the block bearings and the
connecting rod bearings.

- Check that the crankshaft axial play res­training surfaces show no signs of wear.
For checking dimensions follow the sti­pulations for checking axial play and
dimensions for the crankshaft.

94

ENGINE - CRAKCASE AND CRANKSHAFT

Checking the bearings

- In order to ensure good lubrication of
the bearings it is necessary to achieve
optimum lubrication oil pressure (4 bar)
and a good flow of oil, and in this res­pect it is essential that the bearings are
correctly located to avoid causing obs­tructions to the oil supply oil ways.

- The block bearings are made up of 2
half bushes, one solid, and the other
with perforations and channels for lubri­cation.

- The solid half bush is intended to sup­port the thrust caused by the combus­tion, and is therefore to be located on
the side opposite to the cylinder.

- So as to avoid obstructing the oil feed
channels it is vital that the mating plane
of the half bushes is perfectly perpendi­cular to the cylinder axis, as shown in
the figure.

- The section of the oil supply oil ways is
also affected by the depth to which the
bearings are inserted with respect to the
crankshaft axial play restraining plane.

Normal insertion depth 1.35 ÷ 1.6

N.B.: In order to maintain such a posi-

tioning of the bearings with respect to the
crankcase, the insertion is carried out by
applying pressure to steel rings introdu­ced when joining the two crankcase hal­ves.

- The normal diameter of the bearings
after insertion is variable, as a function
of the selection of mating sizes.

- The bearing seating in the crankcase
halves are classified into 2 categories as
for the engine crankshaft, Cat.1 and
Cat. 2.

- The bearings are divide into 3 classes
by their thickness. Please refer to the
table below.

Class Identification
ARed
B Dark Blue
C Yellow

95

ENGINE - CRAKCASE AND CRANKSHAFT

Closing the crankcase

- Fit the internal division and lock the 2
securing screws to the recommended
torque setting.

Torque setting 4 ÷ 6 N·m.

- Fit the oil filter connector, and tighten to
the recommended torque setting.

Torque setting 28 ÷ 30 N·m.

- Offer the gasket up to the crankcase
half, together with the centring pins, pre­ferably using the drive side crankcase
half.

- Lubricate the block bearings, insert the
crankshaft into the drive side crankcase
half.

- Mate the two crankcase halves.

N.B.: While assembling the crankcase

halves and the crankshaft, take care to
ensure that no damage is caused to the
block bearings by the crankshaft threa­ded ends.

- Fit the 11 crankcase half securing
screws and tighten to the recommended
torque setting.

Torque setting 11 ÷ 13 N·m

96

ENGINE - CRAKCASE AND CRANKSHAFT

N.B.: Remove any gasket material pro-

truding from the crankcase mating joint
on the cylinder plane, to ensure the best
sealing conditions.

- Lubricate the magneto side oil seal.

- Using the special insertion tool (part
number 19.1.20425) fit the oil seal.

N.B.: Failure to use the correct tool

may lead to an incorrect seating depth
and therefore cause incorrect operation
of the oil seal.

- Fit a new O-Ring to the pre-filter, and
lubricate it.

- Offer up the pre-filter to the engine, and
secure tightening to the recommended
torque setting.

Torque setting 25 ÷ 28 N·m

Assembly of the starter motor

- fit a new O-ring to the starter motor and
lubricate it.

- Assemble the starter motor to the engi­ne crankcase, and tighten the 2 secu­ring screws to the recommended torque
setting.

Torque setting 11 ÷ 13 N·m

- Re-assemble all the remaining parts
as described in the chapters on the
Cylinder, cylinder head and timing,
Lubrication, Magneto, and Drive.

97

ENGINE - CRAKCASE AND CRANKSHAFT

ENGINE - STARTER MOTOR

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