um DSR EX 125 Instruction manual

ENGINE 125 4T / 4V 6M EURO 4
WORKSHOP MANUAL

This manual has been produced by UM Motorcycles for use by UM dealer and sub-agency workshops.
It is assumed that those using this publication for training purposes and for repairing UM vehicles, have
a basic knowledge of mechanics and of the methods inherent in the technique of vehicle repair. Significant
variations in the characteristics of the machines or in the specific repair operations will be communicated by
means of updates to this manual.
Completely satisfactory work cannot however be carried out without the availability of suitable facilities
and tools, which is why we ask you to consult the pages of this manual referring to special tools and imple-
ments.
Particularly important items of information in this manual are distinguished by the following an N.B.:tions:
N.B.
KEY INFORMATION FOR PERFORMING THE PROCEDURE IN AN EASIER AND CLEARER WAY, OR ANY
ESSENTIAL OPERATION.
UM MOTORCYCLES
The UM logo is the registered trademark and property of UM.
The total or partial reproduction of any photograph, graphical image or text inserted in this ma-
nual is prohibited.© 2017 UM
1
INTRODUCTION
WORKSHOP MANUAL

GENERAL INFORMATION
ENGINE SPECIF ICATIONS
TIGHTENING TORQUES
IDENTIFICATION OF SETS
ELECTRICAL SYSTEM SPECIFICATIONS
LUBRICATION CIRCUIT
COOLANT CIRCUIT
PERIODICAL INSPECTIONS AND ADJUSTMENTS
DISMANTLING THE ENGINE
Camshaft
Timing chain
Cylinder head, cylinder and piston
Flyweel magneto
Clutch
Oil pump
Crankshaft
Crankcases
Transmission, gear selector, gearchange shaft and selector distributor
INSPECTION AND REPAIR
ASSEMBLING AND ADJUSTING THE ENGINE
Transmission, gear selector, gearchange shaft and selector distributor
Crankshaft
Crankcases
Oil pump
Clutch
Flyweel magneto
Camshaft
Timing chain
Installing the piston rings
Cylinder head, cylinder and piston
FUEL SUPPLY
Pag. 4
Pag. 12
Pag. 13
Pag. 15
Pag. 19
Pag. 21
Pag. 23
Pag. 34
Pag. 33
Pag. 33
Pag. 34
Pag. 36
Pag. 40
Pag. 41
Pag. 43
Pag. 44
Pag. 45
Pag. 46
Pag. 48
Pag. 58
Pag. 59
Pag. 63
Pag. 66
Pag. 68
Pag. 70
Pag. 75
Pag. 78
Pag. 81
Pag. 84
Pag. 85
Pag. 91
3
INDEX
WORKSHOP MANUAL
Diagram wiring
APPENDIX :
MAGNETI MARELLI DONGLE INSRUCTION

REGULATIONS
This section describes the machine’s general safety and maintenance work rules.
SAFETY REGULATIONS
- In the event of having to carry out work on the engine while this is running, ensure that the area is well
ventilated, where possible using extractor fans. Never leave engines running in closed spaces. Exhaust gases
are poisonous.
- Petrol is extremely inflammable and in certain conditions may explode. Smoking must not be allowed in the
work area, nor should there be naked flames or sparks.
MAINTENANCE REGULATIONS
Use genuine UM spare parts and lubricants recommended by UM. Non-genuine or unauthorised parts
may damage the machine.
Only use the specific tools intended for this machine.
During assembly, always use new gaskets, oil seals, piston rings and keys.
After dismantling, clean the components with solvents that are non-inflammable or with a high flammability
point. Grease all working surfaces before assembling, excluding tapered joints.
After assembly, check that all components have been correctly fitted and that they are functioning perfectly.
For dismantling, checking and assembly operations use only tools with metric measurements. Metric screws,
nuts and bolts are not interchangeable with imperial measurement joining devices. Using unsuitable tools
and joining devices may damage the machine.
In the case of work on the machine’s electrical circuitry, check that electrical connections have been correctly
fitted, especially the earth connections.
4
GENERAL INFORMATION
WORKSHOP MANUAL

IDENTIFICATION
MODEL CHASSIS CODE ENGINE CODE
DSR EX 125
DSR SM 125
RENEGADE SCRAMBLER CLASSIC 125
RENEGADE SCRAMBLER SPORT 125
DSR ADVENTURE 125
DSR ADVENTURE TT 125
M6FSC0001Hxxxxxxx
M6FDA0001Hxxxxxxx
M6FDS0001Hxxxxxxx
ENGINE CODE
The engine code can be found at the back of the engine,
in front of the rear wheel.
5
GENERAL INFORMATION
WORKSHOP MANUAL
UXPI 125
xxxxxxx

PREPARATION FOR REMOVAL AND DISMANTLING
Remove all the dirt, grime, dust and other foreign material
before removing and dismantling.
Use properly cleaned tools and equipment.
See “ SPECIAL TOOLS ”.
On dismantling parts, always keep related items together.
This includes gears, cylinders, pistons and other parts sub-
mitted to natural wear together. Related parts must always
be reassembled or replaced together.
While dismantling the motorcycle, clean all the parts and lay
them out on trays in the order dismantled. This speeds up re-
assembly and ensures the correct fitting of all the parts.
Keep all parts away from any contact with fire.
P
6
GENERAL INFORMATION
WORKSHOP MANUAL

SPARE PARTS
Use only genuine UMspare parts. For all lubrication tasks,
use oils and greases recommended by UM. Other makes
make seem similar in their function and appearance, but are
inferior in quality.
SEALS, RETAINING RINGS AND O-RINGS
Renew all seals, retaining rings and O-rings when servicing
the engine.
All surfaces receiving seals, retaining ring edges and O-rings
must be cleaned.
Apply oil to all paired parts and bearing during reassembly.
Apply grease to the retaining ring edges.
TAB/SPACER WASHERS AND SPLIT PINS
After removing them, renew all tab/spacer washers (1) and
split pins. Bend the tabs to fit the flat surfaces of the bolt or
nut once they have been tightened to the specified torque.
BEARINGS AND RETAINING RINGS
Fit bearings and retaining rings in such a way that the ma-
nufacturers marks remain visible. On fitting retaining rings,
applying a thin film of light lithium soap based grease to
their edges. Where required, apply oil generously when fit-
ting bearings.
WARNING
DO NOT USE COMPRESSED AIR TO DRY BEARINGS. THIS
DAMAGES THE BEARING SURFACES.
T
7
GENERAL INFORMATION
WORKSHOP MANUAL

LOCKING RINGS
Examine all the locking rings carefully before fitting. Always
replace the gudgeon pin circlips after every use. Replace dis-
torted locking rings. On fitting a locking ring (1), ensure that
the sharp edge (2) is on the opposite side to the force (3) to
be applied to it.
See the figure on the side, (4) Shaft.
SPECIAL TOOLS
The following special tools are needed for assembly and for
complete and exact adjustments. Only use the proper special
tools; thereby avoiding damage caused by the use of unsui-
table tools or improvised techniques.
Ref. 865260
The camshaft sprocket locking tool.
Ref. 865259
Magneto flywheel locking tool.
8
GENERAL INFORMATION
WORKSHOP MANUAL
TDC measuring tool.
Ref. T01010047
Ref. T01010046

9
Ref. 864592
TDC measuring tool.
Ref. 00H05300041
Clutch bell housing fitting tool.
Ref. 864486
Balance shaft locking tool.
Ref. 864567
Set of camshaft locking keys.
GENERAL INFORMATION
WORKSHOP MANUAL
Ref. T01010045
Ref. T01010042
Ref. T01010043
Ref. T01010044

Ref. 864487
Crankshaft sprocket locking tool.
Ref. 864868
Magneto flywheel extractor tool.
Ref. 865261
Piston fitting clamp.
Ref. 865207
Set of tools for 125cc 4-stroke 4 valve engine.
10
GENERAL INFORMATION
WORKSHOP MANUAL
Ref. T01010050
Ref. T01010051
Ref. T01010049
Ref. xxxxxxxx

Engine
Diameter x stroke
Cubic capacity
Cooling
Starter
Compression ratio
Maximum nominal power
Fuel
Lubrication system
Ignition
Primary transmission
EURO 4 single cylinder 4-stroke
58x47 mm
124.2 cm 3
Water
Electric
12:1
Lead-free petrol
Semi-wet crankcase
C.D.I type electronic ignition
Gearing
Cv: 15,5 Kw:11,4 a 9250 at the crankshaft
Cv: 14,0 Kw:10,3 a 9250 at the rear wheel
Type of oil
Engine oil
Viscosity
Total capacity
AGIP CITY 4T
SAE 10W-40
1150 ml
Power Supply
EFI
MAGNETI MARELLI
CM128218
Spark Plug
Type
Gap between electrodes NGK CR8EB
0,7 ÷0,8 mm
Clutch 6 driving disks and 5 driven disks
Oil filter
Reference
Paper cartridge
874081
Air filter
Reference
Laminated paper
861130
11
GENERAL INFORMATION
WORKSHOP MANUAL

TRANSMISSION
Primary transmission ratio
First gear ratio
Second gear ratio
Third gear ratio
Fourth gear ratio
Fifth gear ratio
Sixth gear ratio
Secondary transmission ratio
12
ENGINE SPECIFICATIONS
WORKSHOP MANUAL
- 2,38
- 3
- 2
- 1,5
- 1,2
- 1,08
- 0,96
- 14/51 = 3,64

Spark plug
Rocker cover
Camshaft bridge
Timing crown wheel 1
Timing crown wheel 2
Cylinder head
Cylinder head
Inlet pipe
Thermostat cover
Coolant temperature sensor
Timing chain tensioner
Timing chain tensioner spring
Water pump cover
Water pump turbine
Clutch control cam
Oil filter cover
Oil pressure sensor
Clutch cover
Clutch spring
Clutch bell housing-ram
Balance shaft
Crankshaft-clutch bell housing gear
Timing chain roller.
Oil pump
Selector drum flor.
Selector drum flor. locking cam
Starter motor
Phase inspection cover
Magneto side oil filter cover
PARTS TO BE TIGHTENED DESCRIPTION THREAD
MEASUREMENT QTY. TIGHTENING TORQUE
Kgf.m N·m Obs.
-
Bolt
Bolt
Bolt
Bolt
Bolt
Bolt
Bolt
Bolt
-
Bolt
Cover
Bolt
-
Bolt
-
-
Bolt
Bolt
Nut
Nut
Nut
Bolt
Bolt
Bolt
Bolt
Bolt
-
-
M10
M6
M6
M8
M8
M8
M6
M6
M6
M10
M6
-
M5
M5
M6
M56x1,5
M10
M6
M5
M12
M10
M12
M6
M5
M5
M6
M6
M18X1,5
M28X1
1
4
8
1
1
4
2
3
2
1
2
1
3
1
1
1
1
10
5
1
1
1
1
3
1
1
2
1
1
1,2-1,4
1-1,2
1-1,2
2,5-2,7
2,5-2,7
2,7+90°
1,1-1,3
1,1-1,3
1-1,2
0,8-1,0
1,1-1,3
0,8-1
0,5-0,6
0,4-0,6
0,8-1,0
2,4-2,6
1,2-1,4
1,1-1,3
0,35-0,45
3,5-4,5
3,5-4,5
7,5-8,3
1-1,2
0,5-0,6
0,35-0,45
0,8-1,0
1,1-1,3
0,35-0,45
2,4-3,0
12-14
10-12
10-12
25-27
25-27
27+90°
11-13
11-13
10-12
8-10
11-13
8-10
5-6
4-6
8-10
24-26
12-14
11-13
3,5-4,5
35-45
35-45
75-83
10-12
5-6
3,5-4,5
8-10
11-13
3,5-4,5
24-30
13
TIGHTENING TORQUES
WORKSHOP MANUAL

PIEZAS A APRETAR DESCRIPCIÓN MEDIDA DE
LA ROSCA CANT. TORQUE DE APRIETE
Kgf.m N·m Obs.
Magneto cover
Oil sensor cable securing device
Neutral sensor indicator
Oil dipstick
Magneto stator
Pick-up. ( R.P.M. sensor)
Starter crown wheel clamp
Magneto rotor
Magneto rotor- starting clutch
Semi crankcases joint
Bolt
Bolt
-
-
Bolt
Bolt
Bolt
Nut
Bolt
Bolt
M6
M4
M10x1,25
M12x1,5
M5
M5
M6
M14x1,5
M6
M6
10
1
1
1
2
2
1
1
6
12
1,1-1,3
0,3-0,5
0,8-1,0
0,4-0,6
0,5-0,7
0,3-0,4
0,5-0,6
8,3-9,0
1,1-1,3
1,1-1,3
11-13
3-5
8-10
4-6
5-7
3-4
5-6
83-90
11-13
11-13
14
TIGHTENING TORQUES
WORKSHOP MANUAL

½CRANKSHAFT DIAMETER
S/T BALANCE SHAFT GEARINGENGRANAJES
PRIMARY SHAFT GEARING
CLASS 1
CLASS 2
MIN
32.480
32.485
CRANKSHAFT DIAMETER
REFERENCE
8711475001
8711475002
MAX
32.485
32.490
2
T
Y
2
T
Y
S SET
T SET
CRANKSHAFT GEAR
REFERENCE
8711565001
8711565002
REFERENCE
8714465001
8714465002
N.B.: The crankcases available as spare parts are always of the S kind.
BALANCE SHAFT – GEAR SET
S CLASS
T CLASS
MIN
64.03
64.00
64.00
63.97
MAX
BALANCE GEAR
N.B.: The distances between the balance shaft and the crankshaft are the following.
2
T
Y
15
SETS IDENTIFICATION
WORKSHOP MANUAL
CRANKCASE LOCATION
Go to spare parts catalogs
Go to spare parts catalogs
Go to spare parts catalogs
Go to spare parts catalogs
Go to spare parts catalogs
Go to spare parts catalogs

X or Y S or T
Distances between gears
With the aim of minimising noise and friction, the cranks-
haft, primary shaft and balance shaft gears exist as joint
assemblies.
PRIMARY SHAFT- GEAR SET
X CLASS
Y CLASS
CRANKSHAFT GEAR
REFERENCE
8714605001
8714605002
REFERENCE
8714475001
8714475002
N.B.: The crankcases available as spare parts are always of the X kind.
X CLASS
Y CLASS
MIN
86.04
86.00
86.00
85.96
MAX
BALANCE GEAR
N.B.: the distances between the primary shaft and the crankshaft are the following.
16
SETS IDENTIFICATION
WORKSHOP MANUAL
Go to spare parts catalogs
Go to spare parts catalogs
Go to spare parts catalogs
Go to spare parts catalogs

VALVE GUIDES
M
N
O
P
MIN
58.010
58.017
58.024
58.031
CATEGORY
PISTON REFERENCE
8745340001
8745340002
8745340003
8745340004
MAX
58.017
59.024
58.031
58.038
IRON CYLINDER AND PISTON SETS
CYLINDERPISTON
MIN
57.953
57.960
57.967
57.974
MAX
57.960
57.967
57.974
57.981
N.B.: Clearance on assembling 0.050 - 0.064
The cylinder is only available as a spare part in a kit with the piston. Reference 874533
CATEGORY
THICKNESS
1
2
3
4
5
6
7
8
9
10
11
12
THICKNESS
2,20
2,25
2,30
2,35
2,40
2,45
2,50
2,55
2,60
2,65
2,70
2,75
REFERENCE
CM222701
CM222702
CM222703
CM222704
CM222705
CM222706
CM222707
CM222708
CM222709
CM222710
CM222711
CM222712
N.B.: In the markings on the inside of the valve, you will find for example:
20, corresponding to 2.20 in the table.
17
SETS IDENTIFICATION
WORKSHOP MANUAL
Go to spare parts catalogs
Go to spare parts catalogs
Go to spare parts catalogs
Go to spare parts catalogs
Go to spare parts catalogs

CLASE 1
CLASE 2
RED
BLUE
MIN
2.005
2.010
HALF-BEARING THICKNESS
Lower Ref.
864591
864590
MAX
2.010
2.015
Upper Ref.
864589
864588
CRANKSHAFT
CRANKCASE
Example:
Based on an engine comprising a Class A crankcase (diameter between 36.500 and 36.508 mm), and a Class
2 crankshaft (diameter between 32.485 and 32.490 mm), two RED type bearings should be fitted, Ref. 864591
and 864589.
If the crankcases have mixed bearings, they can be fitted regardless of their initial location.
CLASS B
BLUE+BLUE
RED+BLUE
CLASS A
RED+BLUE
RED+RED
CLASS 1
CLASS 2
MIN
32.480
32.485
CRANKSHAFT DIAMETER
REFERENCE
8711475001
8711475002
MAX
32.485
32.490
CLASS A
CLASS B
MIN
36.508
36.516
36.500
36.508
MAX
CRANKCASE MACHINED DIAMETER (D1)
HALF-BEARING
D1
18
SETS IDENTIFICATION
WORKSHOP MANUAL
RANKCASE
Go to spare parts catalogs
Go to spare parts catalogs
Go to spare parts catalogs
Go to spare parts catalogs
Spare Parts
Spare Parts
CRANKSHAFT
HALF-BEARING

IGNITION
DESCRIPTION OF THE SYSTEM
System logic
- The fundamental parameter is the rpm reading from the
pick-up
- Based on the information from this sensor the ECU calcula
tes the moment in which the spark plug should fire.
Components
- Engine rpm sensor (pick-up)
Sensor resistance: 105 -124 _ at 20º C
(magneto side connector between R and B cable).
- Ignition coil
Resistance of primary winding
0,21 +/- 0,025 at 25+/-5º C
Resistance of secondary winding
3,1 K +/- 0,31 K at 25 +/-5º C
Primary winding Secondary winding Resistance of spark plug cap
5 K at 20 ° C
Red (R)
Black (B)
19
ELECTRICAL SYSTEM SPECIFICATIONS
WORKSHOP MANUAL