1. Coolant reservoir cap
2. Maximum level mark
3. Minimum level mark
ECA10471
CAUTION:
●If coolant is not available, use
distilled water or soft tap water
instead. Do not use hard water
or salt water since it is harmful
to the engine.
●If water has been used instead
of coolant, replace it with coo-
lant as soon as possible, other-
wise the cooling system will
not be protected against frost
and corrosion.
●If water has been added to the
coolant, have a Yamaha dealer
check the antifreeze content ofthe coolant as soon as possi-
ble, otherwise the effective-
ness of the coolant will be
reduced.
EWA10380
s s
WARNING
Never attempt to remove the radia-
tor cap when the engine is hot.
5. Close the reservoir cap, and then
install the cowling.
EAU33030
Changing the coolantEWA10380
s s
WARNING
Never attempt to remove the radia-
tor cap when the engine is hot.
The coolant must be changed at the
intervals specified in the periodic
maintenance and lubrication chart.
Have a Yamaha dealer change the
coolant.
EAU40370
Air filter element
The air filter element must be cleaned
and replaced at the intervals specified
in the periodic maintenance and lubri-
cation chart. Have a Yamaha dealer
clean and replace the air filter ele-
ment.
PERIODIC MAINTENANCE AND MINOR REPAIR
6-9
6
5RW-F8199-E4.QXD 19/11/07 08:01 Página 44
Engine overheating (for CS50Z)EWA10400
s s
WARNING
●Do not remove the radiator cap when the engine and radiator are hot. Scalding hot fluid and steam may be
blown out under pressure, which could cause serious injury. Be sure to wait until the engine has cooled.
●After removing the radiator cap retaining bolt, place a thick rag, like a towel, over the radiator cap, and then
slowly rotate the cap counterclockwise to the detent to allow any residual pressure to escape. When the his-
sing sound has stopped, press down on the cap while turning it counterclockwise, and then remove the cap.
PERIODIC MAINTENANCE AND MINOR REPAIR
6-26
6
Wait until the
engine has cooled.Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.
The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer checkand repair the cooling system.
Add coolant. (See NOTE.)
Start the engine. If the engine overheats again, have a
Yamaha dealer check and repair the cooling system.
There is
leakage.
There is
no leakage.
NOTE:
If coolant is not available, tap water can be temporarily used instead, provided that it is changed to the recommended
coolant as soon as possible.
5RW-F8199-E4.QXD 19/11/07 08:01 Página 61
Dimensions:Overall length:
1740 mm (68.5 in)
Overall width:
675 mm (26.6 in)
Overall height:
1065 mm (41.9 in)
Seat height:
770 mm (30.3 in)
Wheelbase:
1210 mm (47.6 in)
Ground clearance:
132 mm (5.19 in)
Weight:With oil and fuel:
CS50/CS50M: 81.0 kg (178.6 lb)
CS50Z: 84.0 kg (185.2 lb)
Engine:Engine type:
CS50/CS50M: Air cooled 2-stroke
CS50Z: Liquid cooled 2-stroke
Cylinder arrangement:
Forward-inclined single cylinder
Displacement:
49.0 cm
3(2.99 cu.in)
Bore x stroke:
40.0 x 39.2 mm (1.57 x 1.54 in)
Compression ratio:
CS50: 11.60:1
CS50M: 10,10 :1
CS50Z: 11.40 :1
Starting system:
Electric starter and kickstarterLubrication system:
Separate lubrication (Yamaha autolube)
Engine oil:Type:
YAMALUBE 2-cycle oil or 2-stroke engine
oil (JASO FC grade) or (ISO EG-C or EG-
D grade)
Engine oil quantity:
Quantity:
1.4 L (1.48 US qt) (1.23 Imp.qt)
Final transmission oil:Type:
SAE10W30 type SE motor oil
Quantity:
0.11 L (0.12 US qt) (0.10 Imp.qt)
CS50Z: Cooling system:Coolant reservoir capacity (up to the maxi-
mum level mark):
0.25 L (0.26 US qt) (0.22 Imp.qt)
Radiator capacity (including all routes):
0.91 L (0.96 US qt) (0.80 Imp.qt)
Air filter:Air filter element:
Wet element
Fuel:Recommended fuel:
Regular unleaded gasoline only
Fuel tank capacity:
5.5 L (1.45 US gal) (1.21 Imp.gal)
Fuel reserve amount
1.9 L (0.50 US gal) (0.42 Imp.gal)
Carburetor:Manufacturer:
GURTNERType x quantity:
PY 12 x 1
Spark plug(s):Manufacturer/model:
CS50-CS50Z: NGK/BR8HS
CS50M: NGK/BPR4HS
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
Clutch:Clutch type:
Dry, centrifugal automatic
Final transmission oil:Primary reduction system:
Helical gear
Primary reduction ratio:
52 x 13 (4.000)
Secondary reduction system:
Spur gear
Secondary reduction ratio:
CS50: 42 x 13 (3.231)
CS50M: 45 x 12(3.750)
CS50Z: 43 x 13 (3.308)
Transmission type:
V-belt automatic
Operation:
Centrifugal automatic type
Chassis:Frame type:
Steel tube underbone
Caster angle:
25.00 °
Trail:
80.0 mm (3.15 in)
SPECIFICATIONS
8-1
8
5RW-F8199-E4.QXD 19/11/07 08:01 Página 66
Coolant temperature warning light:LED x 1
Fuses:Main fuse:7.5 A
SPECIFICATIONS
8-3
8
5RW-F8199-E4.QXD 21/11/07 11:37 Página 68
2-stroke engine oil tank .............................3-9
AAcceleration and deceleration ...................5-2
Air filter element .........................................6-9
Auxiliary light bulb, replacing ...................6-23
BBattery......................................................6-19
Brake fluid level, checking .......................6-15
Brake fluid, changing ...............................6-16
Brake lever, front ........................................3-6
Brake lever, rear .........................................3-7
Brake levers, lubricating ..........................6-16
Brake pads and shoes, checking ............6-14
Braking .......................................................5-3
C
Carburetor,adjusting.................................6-10
Care............................................................7-1
Catalytic converter .....................................3-8
Centerstand,Checking and lubricating ....6-17
Coolant.......................................................6-8
Coolant temperature warning light ............3-3
Cowling and panel, removing
and installing............................................6-5
DDimmer switch ...........................................3-6
EEngine break-in ..........................................5-4
Engine oil ...................................................3-9
FFinal transmission oil .................................6-7
Front brake lever free play, checking.......6-13
Front fork, checking .................................6-17
Fuel ............................................................3-8
Fuel and 2-stroke engine oil tank caps .....3-7Fuel consumption, tips for reducing ..........5-3
Fuse, replacing.........................................6-20
HHandlebar switches ...................................3-6
Headlight and front turn signal light
bulb, replacing .......................................6-21
High beam indicator light...........................3-2
Horn switch ................................................3-6
IIdentification numbers ...............................9-1
Indicator and warning lights ......................3-2
KKey identification number ..........................9-1
Kickstarter ................................................3-10
LLuggage hook ..........................................3-12
MMain switch/steering lock ..........................3-1
Matte color, caution ...................................7-1
Model label ................................................9-2
Multi-function display ................................3-4
OOil level warning light .................................3-2
PParking .......................................................5-4
Part locations .............................................2-1
Periodic maintenance and lubrication
chart .........................................................6-2
Pre-operation check list .............................4-2
RRear brake lever free play, adjusting .......6-13
SSafe-riding points.......................................1-4
Safety information ......................................1-1Seat ..........................................................3-10
Spark plug, checking .................................6-6
Specifications.............................................8-1
Speedometer .............................................3-3
Start switch ................................................3-6
Starting a cold engine ................................5-1
Starting off .................................................5-2
Steering, checking ...................................6-18
Storage.......................................................7-3
Storage compartment ..............................3-11
TTail/brake light bulb or rear turn signal
light bulb, replacing ...............................6-22
Throttle cable free play, adjusting ............6-10
Throttle grip and cable, checking and
lubricating ..............................................6-16
Tires .........................................................6-11
Troubleshooting .......................................6-24
Troubleshooting charts ............................6-25
Turn signal indicator lights .........................3-2
Turn signal switch ......................................3-6
VVehicle identification number .....................9-1
WWheel bearings, checking........................6-19
Wheels .....................................................6-12
1
INDEX
5RW-F8199-E4.QXD 19/11/07 08:01 Página 71