SHERCO 125 SE FACTORY Instruction manual

1
TABLE
FORWARD .............................................................................................................................................. 4
TOOLS LIST 125SE-R ............................................................................................................................... 5
TECHNICAL SPECIFICATION ................................................................................................................. 6
ENGINE ................................................................................................................................................... 6
CARBURETOR ...................................................................................................................................... 6
CYCLE PART ........................................................................................................................................... 7
FORK ...................................................................................................................................................... 7
SHOCK ABSORBER ................................................................................................................................. 8
OPERATIONS REQUIRING DISASSEMBLY OR NOT ENGINE ....................................................................... 9
REMOVING REISTALLING THE ENGINE ......................................................................................... 10
REMOVING THE ENGINE ................................................................................................................... 10
REINSTALLING THE ENGINE ............................................................................................................ 10
ENGINE DISASSEMBLY ..................................................................................................................... 11
❱❘ Gear box drainage ............................................................................................................................................ 11
❱❘ Gear box drainage ............................................................................................................................................ 11
❱❘ Removal of the cylinder head / the cylinder / the piston ................................................................................... 1
❱❘ Disassemble the clutch cover ........................................................................................................................... 13
❱❘ Removal of both the pressure tray and discs ................................................................................................... 13
❱❘ Removal of the electric starter .......................................................................................................................... 14
❱❘ Removal of the main transmission .................................................................................................................... 14
❱❘ Removal of the locking mechanism .................................................................................................................. 15
❱❘ Removal of the ignition ..................................................................................................................................... 15
❱❘ Removal of the starter ....................................................................................................................................... 16
❱❘ Intake pipe and clapper box .............................................................................................................................. 16
❱❘ Separate out the half casings ........................................................................................................................... 16
❱❘ Removal of the speed selection ........................................................................................................................ 17
ENGINE PARTS CONTROL ................................................................................................................ 18
❱❘ Connecting rod assembly ................................................................................................................................. 18
❱❘ Balance masses, verification of the exterior side .............................................................................................. 18
❱❘ Radial clearance of the crank head .................................................................................................................. 18
❱❘ Crank head lateral clearance ............................................................................................................................ 19
❱❘ Control of the crankshaft radial runout .............................................................................................................. 19
❱❘ Piston ................................................................................................................................................................ 19
❱❘ Cross sectional clearance ................................................................................................................................. 0

❱❘
Verifi ation of the state of ylinder wear / Piston ......................................................................... 20
❱❘ Disassemble the exhaust valve system ............................................................................................................ 1
❱❘ Assemble the exhaust valve system ................................................................................................................. 3
❱❘ Exhaust valve setting ........................................................................................................................................ 4
❱❘ Clapper box pipe, Pipe intake sleeve ............................................................................................................... 5
❱❘ Clutch ................................................................................................................................................................ 5
❱❘ Connecting Rod Assembly ................................................................................................................................ 6
❱❘ ........................................................................................................................................................................... 6
• Coat lubricant on the fork guiding tip and insert the rings [1] from the top .................................................. 6
• Fasten the supporting washer[ ] onto the secondary shaft ......................................................................... 6
• Present the primary and secondary shafts together, then drive them into their respective bearings until
reaching the stop. ................................................................................................................................................. 6
• Hook the forks into the grooves of the moving pinions and insert the drum into its bearing ....................... 6
❱❘ Assembly of the half casings ............................................................................................................................ 7
❱❘ Selection mechanism ........................................................................................................................................ 8
❱❘ Main transmission and clutch ............................................................................................................................ 9
❱❘ Clutch discs pressure plate ............................................................................................................................... 30
❱❘ Clutch casing ..................................................................................................................................................... 30
❱❘ Piston and cylinder ............................................................................................................................................ 31
❱❘ Cylinder head .................................................................................................................................................... 31
❱❘ Clapper box and pipe intake ............................................................................................................................. 3
❱❘ Gearbox output pinion ....................................................................................................................................... 3
❱❘ Assembly of the ignition starter ......................................................................................................................... 3
❱❘ Ignition assembly and its cover ......................................................................................................................... 33
❱❘ Assembly of the electric starter ......................................................................................................................... 33
TABLE OF TIGHTENING TORQUES .................................................................................................. 34
TABLE OF CARBURETOR SETTINGS ............................................................................................... 35
ELECTRICAL PART ............................................................................................................................ 36
❱❘ Electrical components ....................................................................................................................................... 36
❱❘ 1- Fan control .................................................................................................................................................... 37
❱❘ -CDI ................................................................................................................................................................. 37
❱❘ 3-Checking voltage regulator ............................................................................................................................ 37
❱❘ 4-Battery check ................................................................................................................................................. 38
❱❘ 5-starter check .................................................................................................................................................. 38
❱❘ 6-Checking the alternator .................................................................................................................................. 38
❱❘ 7-Checking the (crankshaft) hall sensor ........................................................................................................... 39
❱❘ 8-Temperature sensor check ............................................................................................................................ 39
❱❘ 9-Checking the ignition coil ............................................................................................................................... 40
❱❘ 10-Checking the valve moto. ............................................................................................................................ 40
DIAGNOSTIC TOOL SYNERJECT
)
................................................................................................... 41
SYNERJECT
)
SYSTEM PRESENTATION ........................................................................................ 41
1.1- Components Identification ......................................................................................................................... 41

3
125 SE-R
1. - Description Exxodiag diagnostic Tools Ref: kit 8561 .............................................................................. 41
1.3- Diagnostic tool kit contents. ...................................................................................................................... 4
1.4- Installation of the diagnostic tool. ............................................................................................................. 4
PRESENTATION OF THE SOFTWARE .............................................................................................. 46
.1- Connection with keyless system ............................................................................................................... 46
. - Software settings .............................................................................................................................................. 48
.3- Update menu and synchronization ........................................................................................................... 49
3 - Use of the software ...................................................................................................................................... 51
3.1 Identification ................................................................................................................................................. 51
3. Reading trouble codes ................................................................................................................................. 5
3.3 Erasing fault codes ...................................................................................................................................... 54
3.4 Actuator test ................................................................................................................................................. 55
3.5 ECU update ................................................................................................................................................... 57
3.6 Print screen function ................................................................................................................................... 59
WIRING DIAGRAM .............................................................................................................................. 60
❱❘ Main harness (Ref: 7107) ................................................................................................................................... 60
WIRING DIAGRAM .............................................................................................................................. 61
❱❘ Homologated light diagram (Ref: 8145) ............................................................................................................ 61
.............................................................................................................................................................................. 61
WIRING DIAGRAM .............................................................................................................................. 62
❱❘ Racing light diagram (Ref: 845) ....................................................................................................................... 6
.............................................................................................................................................................................. 6
WIRING DIAGRAM .............................................................................................................................. 63
❱❘ Fan harness (Ref: 3577)...................................................................................................................................... 63
.............................................................................................................................................................................. 63

FORWARD
The present manual is primarily intended for certified mechanics working in an
appropriately equipped workshop.
Performing the various operations requires both a solid knowledge in mechanics and the set of
SHERCO tools specific to the 125 SE-R engines.
This workshop manual serves as a complement to the SHERCO 125 SE-R user’s manual

5
125 SE-R
TOOLS LIST 1 5SE-R
Tooling reference Designation
1814
Clutch drum block
1815
Ignition block
10480
1 5 SBS Valve tool control
2067
Oscillating arm shaft tool
2072
Right-hand casing primary shaft bearing tool
2074
Secondary shaft bearing tool
R467
Out-of-gearbox shaft bearing tool
2069
Out-of-gearbox gasket tool
2071
Right-hand drum bearing selection tool
5398
Left-hand drum bearing selection tool
5399
Crankshaft bearing tool
2069
Crankshaft gasket tool
5402
HK0808 needle bearing cage tool (water pump, starter)
1968
Water pump gasket tool
1821
Engine support
1817
Primary pinion block tool
2073
Spring block (finger pointing device)
R462
Magnetic wheel wrench
R464
Crankshaft ring extractor
R453
Selected shaft bearing assembly tool
R444
Gasket selector tool

6
TECHNICAL SPECIFICATION
ENGINE
Type Liquidcooled, -strokesinglecylinder
Displacement 1 4.81CC
Bore diameter/Stroke 54/54.5mm
Gasoline Unleadedwithanoctaneindexofatleast95mixedwithtwo-stroke oil
( %)
Coolant With forced circulation
Ignition system ADC-CDI without a contact breaker, digital advance
Sparkplug NGKBR9ECMIX
Distance between spark plug
electrodes
0.7mm
Piston Forge aluminum
Motor oil 500ml SAE 5W40
Main transmission 0x7
Gearbox:
1
st
nd
3
rd
4
th
5
th
6th
6speeds
15:33
17:30
19: 8
1: 6
3: 4
5:
Final transmission 13x51
Clutch Multi-disc in an oil bath, hydraulic controls
Ignition Electric starter
Ba
t
tery 1 V4Ah
Alternator 0W
CARBURETOR
Type of carburetor KEIHIN PWK36 SAG
Needle position 3
rd
position from the top
Injector needle N1EE
Main injector KEA170(KEA115)
Braking injector KEP4 (KEA38)
Starter injector 85(50)
Opening of the air regulator
screws
1T1/4
Sliding gate section 5.5

7
125 SE-R
TECHNICAL SPECIFICATION
CYCLE PART
Frame
Semi
-
perimeter CrMo steel with aluminum
sub frame
Fork KAYABA USD Ø48mm Closed cartridge
Rear suspension
KAYABA suspension with separate cylinder
Aluminum swing arm
Travel Front/Rear FACTORY 330/330mm
RACING 300/330mm
Front brake rotor Ø 60mm
Rear brake rotor Ø 0mm
Brake disc Limit : .7mm front et 3.6mm rear
Front tire 90/90- 1’’
Rear tyre 140/80-18’’
Pressure front / Rear 0.9 bar
Fuel tank capacity 10.4Ll with1 liter of reserve
Angle of the steering column
5.9°
Wheel base 1465mm
Weight (without fuel) 95 kg
FORK
Settings – Fork KAYABA USD Ø48 mm
Compression Comfort 0 clicks back
Standard 13 clicks back
Sport 8 clicks back
Rebound Comfort 18 clicks back
Standard 13 clicks back
Sport 10 clicks back
Spring Rider weight : 65-75 kg 4.0N/mm (Original)
Rider weight : 75-85 kg 4. N/m
Rider weight : 85-95 4.4N/m
Fork oil 01M 345 CC

8
STANDARD ADJUSTMENT
SHOCK ABSORBER
Factory Settings – KAYABA shock absorber
Low-speed compression Comfort 0 clicks back
Standard 14 clicks back
Sport 1 clicks back
High-speed compression Comfort ,5 turns back
Standard 1.5 turns back
Sport 1 turn back
Rebound Comfort 15 clicks back
Standard 13 clicks back
Sport 11 clicks back
Spring stiffness Rider weight : 65-75 kg 46N/mm
Rider weight : 75-85 kg 48N/mm (original)
Rider weight : 85-95 kg 50N/mm
Type of oil K C

9
125 SE-R
OPERATIONS REQUIRING DISASSEMBLY OR NOT ENGINE
Operation requiring engine removal Operation not requiring engine
removal
Crankshaft (including the crank kit)
•
Complete gearbox
•
Crankshaft bearing
•
Gearbox bearing
•
Piston
•
Cylinder
•
Cylinder head
•
Ignition
•
Starter gear set
•
Complete clutch
•
Water pump
•
Speed selection assembly
•

10
REMOVING / REISTALLING THE ENGINE
REMOVING THE ENGINE
• Drain (refer to the owner’s manual)
- the engine oil
- the engine coolant
• Remove the seat.
• Disconnect the battery.
• Remove the fuel tank and its covers.
• Disconnect all the electrical wiring connectors from the engine.
(Starter, TPS sensor, water temperature sensor, coil, fuel injector)
• Remove the exhaust.
• Remove the ignition coil.
• Remove the fuel injector body.
• Remove the chain.
• Remove the chain guard.
• Remove the clutch actuating cylinder.
• Remove all of the water hoses connected to the motor.
• Remove the left radiator.
• Loosen all of the engine bolts.
• Loosen the swing arm bolt.
• Remove the brackets that attach the cylinder head to the chassis.
• Remove the motor mounting bolts.
• Remove the swing arm bolt.
• Remove the motor.
REINSTALLING THE ENGINE
The motor should be reinstalled in the frame in the reverse order of how it was removed. The following
torque values should be utilized.
Tightening torques:
Motor mounting bolts: 60Nm
Swing arm axle nut: 100 Nm
Clutch receiver screws: 10 Nm
Cylinder head bracket bolts: 23Nm
Exhaust mounting bolts: 10Nm
WARNING
To remove the engine, you must remove the swing arm axle, the swing arm and the rear wheel. To keep
the bike from falling, remember to support the chassis with an appropriate jack.
WARNING
When the clutch actuating cylinder is removed the piston is loose. Hold the piston it in place using a
plastic strap.

11
125 SE-R
ENGINE DISASSEMBLY
❱❘ Gear box drainage
• Remove drainage plugs [1] and [2], let
the oil
flow out.
❱❘ Gear box drainage
• Unfold the safety washer tab [3] using a
pushing
device.
• Remove the gearbox output pinion [4].
•
Remove the screw first [5] first and then
the selector.
•
Release the clutch control rod.
1
2
3
4
5

12
ENGINE DISASSEMBLY
❱❘ Removal of the cylinder head / the cylinder / the piston
• Remove the shoulder screws [1] and
release
both the cylinder head and the two
O-rings
• Remove all four nuts [2] and the
cylinder
•
Cover the casing.
• Remove the piston shaft clips.
•
Release the piston shaft.
•
Remove the piston and extract the
needle bearing from the connecting rod
eye.
•
Remove the base joint.
1
2

13
125 SE-R
ENGINE DISASSEMBLY
❱❘ Disassemble the clutch cover
• Unscrew the water pump screws and cover.
Remove the form joint
•
Remove the screws first and then the clutch
casing. Extract the joint.
❱❘ Removal of both the pressure tray and discs
• Loosen the screws of the clutch pressure plate
[1].
•
Remove the screws, springs and spring plates.
• Release both the pressure plate and discs from the
housing.
•
Remove the support part [1] positioned in the
primary shaft.
1
1

14
CAUTION
At the wedge and O-ring.
The main transmission pinion and clutch housing
crown match, which is why they cannot be
changed separately. They must always be
renewed as a pair.
ENGINE DISASSEMBLY
❱❘ Removal of the electric starter
• Unscrew both screws [2]
❱❘ Removal of the main transmission
• Block the pinion at the end of the crankshaft
using tool reference 1817
[3].
• Unscrew the main transmission nut [4] and then
remove it with the tapered washer.
• Insert tool reference 1814 [6], which
serves to
hold the drum and loosen the
nut.
• Remove the tool.
• Remove the drum, the toothed washer,
the housing with the needle cage.
• Removal of the main transmission pinion
1
2
4
3
6

15
125 SE-R
CAUTION
Be extremely careful with the washer left at the
casing bottom.
ENGINE DISASSEMBLY
❱❘ Removal of the locking mechanism
• With a screwdriver, push back on the scorpion so
that it no longer makes contact with the selection
star; next, remove the selection shaft
• Unscrew the hex socket screw [2]
and remove the selection star [3].
❱❘ Removal of the ignition
• Hold the steering wheel with tool 1815 [1]
and unscrew the shoulder nut [ ].
•
Introduce extractor R46 [3] and tear out
the magnetic wheel
[4].
CAUTION
When handling the selection star indexation
slug. The locking lever arm must only be
retracted
when changing the casing.
2
3
1
2
4
3

16
ENGINE DISASSEMBLY
❱❘ Removal of the starter
• Take out the starter [1]
❱❘ Intake pipe and clapper box
• Remove all 4 screws [2]
• Remove the pipe clapper box and the gasket
❱❘ Separate out the half casings
• Reposition the engine so that the ignition side is
facing you.
•
Remove all the fastening screws.
•
Now lift the left half-casing by gently striking the
gearbox output shaft with a plastic mallet in
order to dislodge the other half-casing.
2
1
CAUTION
Avoid to the greatest extent possible introducing a
screwdriver or any tool between the half-casings for the
purpose of separating them. You might damage
the
parting surface.
CAUTION
Be careful when working with the set rings of gearbox
shafts. They might stay stuck inside the casing.

17
125 SE-R
ENGINE DISASSEMBLY
❱❘ Removal of the speed selection
• Remove the transmission gearbox lubrication
tube [1] .
•
Remove the two selector fork shafts [2] and
push them to the side to free the drum.
• Now disengage the selection drum from its
bearing.
•
The selector forks. Remove
• Remove both the primary and secondary
shafts from their bearing
1
1
2
1
1
3
CAUTION
During this removal step, be sure not to lose the small
rollers [3] on the fork caps.
Indicate the association of these rollers with the
corresponding forks for purposes of reassembly.

18
ENGINE PARTS CONTROL
❱❘ Connecting rod assembly
• If the roller bearings have been changed, then the
internal ring that sits against the balance weight
must also be changed.
• Heat the R464 tool to roughly 150°C, then
immediately insert it onto the internal ring.
Ensure that the tool sits squarely on the ring in
order to more effectively transmit the heat and
extract the ring
• To install the new ring, heat the tool once again to
approx. 150°C. Next, insert the new ring and
immediately position it on the reach of the
connecting rod assembly
❱❘ Balance masses, verification of the exterior side
• Using a caliper, measure the outer distance of the
balance masses.
Exterior value: 57.0 + - 0.1 mm
❱❘ Radial clearance of the crank head
• Install the crankshaft on the V and place a dial
gauge [A] against the crank head.
• Push [B] the crank head first toward the gauge
and then in the opposite direction. The
difference between these two measurements
corresponds to the radial clearance.
Crank head radial clearance:
Standard: 0.015 mm - 0.0 5 mm
Tolerance limit : 0.06 mm
If the radial clearance exceeds the tolerance limit,
the crankshaft must be replaced

19
125 SE-R
ENGINE PARTS CONTROL
❱❘ Crank head lateral clearance
• Measuring the lateral clearance of the crank
head
[A].
Crank head lateral clearance :
Standard: 0.7 mm - 0.9 mm
Tolerance limit: 1.15 mm
If the clearance exceeds the tolerance limit,
replace the crankshaft.
❱❘ Control of the crankshaft radial runout
• Set the crankshaft on an alignment device or
on shims laid out in a “V” pattern, and place
a gauge as shown on the image.
•
Now slowly turn the crankshaft. The maximum
difference between the measurements
corresponds to the level of crankshaft
eccentricity.
Out-of-roundness:
Standard: 0.03 mm maximum
Tolerance limit: 0.05 mm
If the eccentricity is incorrect, replace the
crankshaft or else align it to ensure lying within
the tolerance limits.
❱❘ Piston
If you introduce a piston that has already been in
use, the following points would need to be
verified:
Skirt: search for possible smears (clamping).
Slight smears may be removed with a soft stone.
Segment grooves: The segments must not snag
in their groove. To clean in this spot, an older
segment or emery cloth (400-grain).
The segment retainers must be snugly fastened
and not be worn parts.
Segments: Verify the condition and clearance at
the cross-section.