HYOSUNG RT 125 D User manual

ServiceManual
RX 125 D
RX 125 SM
RT 125 D
Kun motor. Udgivet 2009
Holtvej 8-10, Høruphav
6470 Sydals
Telefon: [phone]
Fax: [phone]
E-mail: [email protected]
www.scanmi.dk
CVR: 27 73 31 07

FOREWORD
This manual contains an introductory description on
HYOSUNG  
&  and procedures for its inspection /
service and overhaul of its engine components.
It covers the differences from
 &
 ’s engine and please refer to the
service manual of  (99000
- 94610)
 and
 (99000-97100)  for others which are
not covered in this manual.
Other information considered as generally known is
not included.
Read GENERAL INFORMATION section to
familiarize yourself with outline of the vehicle and
MAINTENANCE and other sections to use as a guide
for proper inspection and service.
This manual will help you know the vehicle better so
that you can assure your customers of your optimum
and quick service.
SERVICING INFORMATION
GROUP INDEX
GENERAL INFORMATION 1
PERIODIC MAINTENANCE
ENGINE 3
2
7
󳣍󳣍This manual has been prepared on the basis
of the latest specification at the time of
publication.
If modification has been made since then,
difference may exist between the content of
this manual and the actual vehicle.
󳣍󳣍Illustrations in this manual are used to show
the basic principles of operation and work
procedures.
They may not represent the actual vehicle
exactly in detail.
WARNING
This manual is intended for those who have
enough knowledge and skills for servicing
HYOSUNG vehicles. Without such knowledge and
skills, you should not attempt servicing by relying
on this manual only.
Instead, please contact your nearby authorized
HYOSUNG motorcycle dealer.
󳟈COPYRIGHT S&T Motors Co., Ltd.
NOTE
 model :

2
HOW TO USE THIS MANUAL
TO LOCATE WHAT YOU ARE
LOOKING FOR :
1. The text of this manual is divided into sections.
2. As the title of these sections are listed on the previous
page as GROUP INDEX, select the section where you are
looking for.
3. Holding the manual as shown at the right will allow you to
find the first page of the section easily.
4. On the first page of each section, its contents are listed.
Find the item and page you need.
SYMBOL
Listed in the table below are the symbols indicating instructions and other information necessary for servicing.
The meaning of each symbol is also included in the table.
Apply THREAD LOCK1324.
Apply or use brake fluid.
Measure in voltage range.
Measure in resistance range.
Measure in current range.
Use special tool.
Measure in continuity test range.
Measure in diode test range.
Torque control required.
Data beside it indicates specified torque.
Apply oil.
Use engine oil unless otherwise specified.
Apply SUPER GREASEA.
Apply SILICONE GREASE.
Apply MOLY PASTE.
Apply BOND1215.
Use fork oil.
DEFINITION
SYMBOL DEFINITIONSYMBOL
Apply SUPER GREASEC.

3
BL : Black with Blue tracer BBr : Black with Brown tracer
BG : Black with Green tracer BO : Black with Orange tracer
BR : Black with Red tracer BW : Black with White tracer
BY : Black with Yellow tracer LB : Blue with Black tracer
LG : Blue with Green tracer LR : Blue with Red tracer
LW : Blue with White tracer LY : Blue with Yellow tracer
BrB : Brown with Black tracer BrW : Brown with White tracer
GB : Green with Black tracer GR : Green with Red tracer
GY : Green with Yellow tracer GrB : Gray with Black tracer
GrR : Gray with Red tracer GrW : Gray with White tracer
OB : Orange with Black tracer OL : Orange with Blue tracer
OG : Orange with Green tracer OR : Orange with Red tracer
OW : Orange with White tracer OY : Orange with Yellow tracer
RB : Red with Black tracer RW : Red with White tracer
WB : White with Black tracer WL : White with Blue tracer
WR : White with Red tracer YB : Yellow with Black tracer
YL : Yellow with Blue tracer YG : Yellow with Green tracer
YR : Yellow with Red tracer
B : Black Gr : Gray Sb : Light blue
L : Blue Lg : Light green W : White
Br : Brown O : Orange Y : Yellow
G : Green R : Red
WIRE COLOR

4

5
GENERAL INFORMATION
EXTERIOR PHOTOGRAPH  6 (1-3)
EXTERIOR ILLUSTRATION
󳛪󳛪󳛫󳛫
 7 (1-7-1)
EXTERIOR ILLUSTRATION
󳛪󳛪󳛫󳛫
 8 (1-7-2)
EXTERIOR ILLUSTRATION
󳛪󳛪󳛫󳛫
 9 (1-7-3)
SPECIFICATIONS 10 (1-8)
CONTENTS
1

6
1-3 GENERAL INFORMATION
EXTERIOR PHOTOGRAPH

7
GENERAL INFORMATION 1-7-1
EXTERIOR ILLUSTRATION
󳛪󳛪󳛫󳛫
390
315
840
940
945
1,125
1,060
230
1,350
2,085
405
790
660
715
725
800
865
Rear
reflector
Brake / Tail lamp
Rear turn signal lamp
License plate lamp
Front turn signal lamp
Passenger footrests
Head lamp
(HEIGHT)
(WHEEL BASE)
(LENGTH)
(WIDTH)

8
1-7-2 GENERAL INFORMATION
EXTERIOR ILLUSTRATION
󳛪󳛪󳛫󳛫
875
720
295
810
410
1,010 1,065
1,160 1,100
1,425
2,190
320 840
865
124cm
3
Rear
reflector
Brake / Tail lamp
Rear turn signal lamp
License plate lamp
Front turn signal lamp
Passenger footrests
Head lamp
(HEIGHT)
(WHEEL BASE)
(LENGTH)
(WIDTH)

9
GENERAL INFORMATION 1-7-3
EXTERIOR ILLUSTRATION
󳛪󳛪󳛫󳛫
Rear
reflector Brake / Tail lamp
Rear turn signal lamp
License plate lamp
Front turn signal lamp
Passenger footrests
Head lamp
(HEIGHT)
(WHEEL BASE)
(LENGTH)
(WIDTH)

10
1-8 GENERAL INFORMATION
2,085 mm (82.1 in)
840 mm (33.1 in)
1,125 mm (44.3 in)
1,350 mm (53.2 in)
230 mm (9.1 in)
135 kg (298 lbs)
2,190 mm (86.2 in)

1,160 mm (45.7 in)
1,425 mm (56.1 in)
295 mm (11.6 in)
130 kg (287 lbs)
Overall length
Overall width
Overall height
Wheelbase
Ground clearance
Mass
ITEM
SPECIFICATIONS
DIMENSIONS AND MASS
Four-stroke, DOHC,
Air & oil cooled
1 cylinder
57.0 mm (2.24 in)
48.8 mm (1.92 in)
124.5  (7.6 in3)
Carburetor
Electric starter
Wet sump
















Type
Number of cylinder
Bore
Stroke
Piston displacement
Fuel system
Starter system
Lubrication system
ITEM
ENGINE
Wet multi-plate type
5-speed constant mesh
1-down, 4-up
3.500
2.750
1.786
1.368
1.046
0.913
428SO, 130 links









428H, 132 links









428H, 130 links
Clutch
Transmission
Gearshift pattern
Reduction ratio
1st
2nd
3rd
4th
5th
Drive chain
ITEM
TRANSMISSION
2,175 mm (85.6 in)

1,145 mm (45.1 in)
1,415 mm (55.7 in)
275 mm (10.8 in)

Gear ratio

11
GENERAL INFORMATION 1-9
NOTE
The specifications are subject to change without notice.
Telescopic type
Swingarm type
47(right & left)
25
84 mm (3.31 in)
Disk brake
Drum brake
130/80 - 18M/C 66P
180/80 - 14M/C 78P
160 mm (6.3 in)


45(right & left)
27.5
94 mm (3.70 in)


2.75 - 21 45P
4.10 - 18M/C 59P
250 mm (9.8 in)



27
88 mm (3.47 in)

Disk brake
110/70 - 17M/C 58H
130/70
- 17M/C 62H

Front suspension
Rear suspension
Steering angle
Caster
Trail
Front brake
Rear brake
Front tire size
Rear tire size
Front fork stroke
ITEM
CHASSIS
ITEM
ELECTRICAL
9.0 
850 
950 
1,200 
215  2.5 cc
8.0 



443  2.5 cc





Fuel tank
Engine oil
Front fork oil capacity (One side)
Oil change
Oil and filter change
Engine overhaul
ITEM
CAPACITIES
Ignition type
Ignition timing
Spark plug
Battery
Fuse
Head lamp
Turn signal lamp
Brake / Tail lamp
License plate lamp
Illumination lamp
High beam indicator lamp
Turn signal indicator lamp(right & left)
Neutral indicator lamp
CDItype
6B.T.D.C. at 1,900 rpm
and 27B.T.D.C. at 4,250 rpm
CR8E
12 V 6 Ah (MF)
15 A
12 V - HS1 : 35 W 1
12 V - HS1 : 35 W 1
12 V - W5 W 1
12 V - RY10 W 4
12 V - P21/5 W 1
12 V - W5 W 1
LED type
12 V - 1.7 W 1
12 V - 1.7 W 2
12 V - 1.7 W 1





12 V - H4 : 60 W 1
12 V - H4 : 55 W 1























HI
LO
Position
󳢬LED : Light Emitting Diode

12

13
2
2
PERIODIC MAINTENANCE
MAINTENANCE PROCEDURES 14 (2-3)
CYLINDER HEAD COVER BOLTS,
CYLINDER HEAD

CYLINDER BASE NUTS,
EXHAUST PIPE NUTS AND MUFFLER BOLTS 14 (2-3)
AIR CLEANER 15 (2-5-1)
VALVE CLEARANCE18 (2-6-1)
SPARK PLUG 20 (2-7)
ENGINE OIL 21 (2-8)
ENGINE OIL FILTER 22 (2-9)
CARBURETOR 23 (2-10)
COMPRESSION PRESSURE CHECK 24 (2-19)
OIL PRESSURE CHECK 25 (2-20)
CONTENTS

14
2-3 PERIODIC MAINTENANCE
Tighten the exhaust pipe nuts , muffler
connecting bolt , and muffler mounting bolts ,
to the specified torque.
Tighten the cylinder head cover bolts to the
specified torque.
CYLINDER HEAD COVER BOLTS,
CYLINDER HEAD & CYLINDER
BASE NUTS, EXHAUST PIPE
NUTS AND MUFFLER BOLTS
Tighten Initial at 1,000 km and Every 4,000 km
thereafter.
Exhaust pipe nut
: 18 ~ 28 Nm (1.8 ~ 2.8 kgfm)
Muffler connecting bolt
: 18 ~ 28 Nm (1.8 ~ 2.8 kgfm)
Muffler mounting bolt
: 18 ~ 28 Nm (1.8 ~ 2.8 kgfm)
Cylinder head cover bolt
: 12 ~ 16 Nm (1.2 ~ 1.6 kgfm)
CYLINDER HEAD COVER BOLT
Tighten the cylinder head base buts and
cylinder base nuts to the specified torque.
Cylinder head base nut
: 7 ~ 11 Nm (0.7 ~ 1.1 kgfm)
Cylinder base nut
: 7 ~ 11 Nm (0.7 ~ 1.1 kgfm)
CYLINDER HEAD & CYLINDER BASE
NUT
EXHAUST PIPE NUTS & MUFFLER
BOLTS
MAINTENANCE PROCEDURES
This section describes the servicing procedures for
each item.
 






Inspect Interval

15
PERIODIC MAINTENANCE 2-5-1
AIR CLEANER
If the air cleaner is clogged with dust, intake
resistance will be increased, with a resultant
decrease in power output and an increase in fuel
consumption.
Check and clean the air cleaner element in the
following manner :

Remove the seat and right side cover.
Remove the six screws and remove the air
cleaner case cover.
Take off the air cleaner element .
Clean the air cleaner element for the follwing :
Fill a washing pan of a proper size with a non-
flammable cleaning solvent 󳟆. Immerse the air
cleaner element in the cleaning solvent and wash
it.
Gently squeeze the air cleaner element between
the palms of both hands to remove the excess
solvent : do not twist or wring the element or it will
develop tears.
Immerse the element in HYOSUNG genuine oil
󳟇, and then squeeze out the excess oil leaving
the element slightly wet.
Reinstall the cleaned or new air cleaner element
in the reverse order of removal.
Clean Every 3,000 km,
Replace Every 12,000 km.


󳟆
󳟇
Inspect Interval

&
16
2-5-2 PERIODIC MAINTENANCE
CAUTION
󳣍󳣍Inspect the air cleaner element for tears.
A torn element must be replaced.
󳣍󳣍If driving under dusty conditions, clean the air
cleaner element more frequently. The surest
way to accelerate engine wear is to operate the
engine without the element or with torn
element. Make sure that the air cleaner element
is in good condition at all times. Life of the
engine depends largely on this component!
8
8
Remove the seat.
The air cleaner is located under the seat.
Remove the four air cleaner element bolts .
Pull up the air cleaner element .




AIR CLEANER OIL DRAIN TUBE
Inspect the air cleaner oil drain tube and drain
water and oil at the periodic interval.
The air cleaner oil drain tube is located beneath
the air cleaner case.


17
PERIODIC MAINTENANCE 2-5-3
8
8
Clean the air cleaner element for the following :
When the air cleaner element clean with the air gun,
necessarily blow at the inside by compressed air.
Carefully examine the air cleaner element for tears
during cleaning. Replace it with a new one if it is torn.
Assemble the element completely or damage
severely the engine.
Be careful not to allow water to go inside the air clea-
ner element.
CAUTION
More frequent servicing may be performed on
motorcycles that are used under severe
conditions, also clean the air cleaner element
when replacing the engine oil to prevent damage
of the engine.

AIR CLEANER OIL DRAIN TUBE
Inspect the air cleaner oil drain tube and drain
water and oil at the periodic interval.
The air cleaner oil drain tube is located beneath
the air cleaner case.

18
2-6-1 PERIODIC MAINTENANCE
Excessive valve clearance results in valve noise and
insufficient valve clearance results in valve damage
and reduced power.
Check the intake and exhaust valve clearances at
the distances indicated above and adjust the valve
clearances to specification, if necessary.
Remove the seat and fuel tank.
Remove the spark plug.
VALVE CLEARANCE
Inspect Initial 1,000 km and Every 4,000 km
thereafter.
Remove the cylinder head cover .
The valve clearance specification is different for both
intake and exhaust valves.
Valve clearance adjustment must be checked and
adjusted :
1) at the time of periodic inspection,
2) when the valve mechanism is serviced, and
3) when the camshafts are removed for servicing.
Remove the magneto cover plug and valve
timing inspection plug .
NOTE
󳣍󳣍
The piston must be at top dead center (TDC)
on the compression stroke in order to check or
adjust the valve clearance.
󳣍󳣍
The valve clearance should only be checked
when the engine is cold.



Inspect Interval

19
PERIODIC MAINTENANCE 2-6-2
To inspect the valve clearance, insert a thickness
gauge between the tappet and the camshaft.
0.1 0.2 mm (0.004 ~ 0.008 in)
0.2 0.3 mm (0.008 ~ 0.012 in)
IN.
EX.
Standard (When cold)Valve clearance
Thickness gauge : 09900-20806
Rotate the magneto rotor clockwise or counter-
clockwise with a socket wrench to set the piston at
TDC on the compression stroke.
(Rotate the magneto rotor until the “T” index mark
on the magneto rotor is aligned with the triangle
mark on the crankcase.)
If the clearance is out of specification, first remove
the cam chain tension adjuster, camshaft housing,
camshaft.
To install the tappet shim at original position,
record the shim NO. and clearance to present by
“A”, “B”, “C”, “D” mark on the cylinder head.
Select the tappet that agree with tappet clearance
(vertical line) and shim NO.(horizontal line) as refer
to the tappet shim selection chart.
(Refer to page 9091)
Adjust valve timing, install the camshaft housing and
the cam chain tension adjuster.
After the crankshaft rotate about 10 times, measure
the valve clearance.
If the clearance be not correct, adjust the standard
clearance as the same manner above.
In case of valve adjustment which is not the tappet
shim selection chart, please follow instructions of
example in the below.
For example, the intake clearance is 0.4 and the
shim is 170 (1.70 mm), select 195 (1.95 mm) of
the shim which 170 (1.70 mm) of the shim add up
the excess clearance 0.25 mm when adjust with
the standard 0.15 as the intake standard clearance
0.10.2 mm.
CAUTION
If you don’t rotate the crankshaft about 10 times
before measuring the valve clearance, there is no
meaning of valve clearance.
