Page 7 of 78

EAU00009
TABLE OF CONTENTS
GIVE SAFETY THE RIGHT OF WAY ..................1-1
DESCRIPTION ....................................................2-1
Left view ............................................................. 2-1
Right view...........................................................2-2
Controls/Instruments ..........................................2-3
INSTRUMENT AND CONTROL FUNCTIONS ....3-1
Main switch/steering lock ................................... 3-1
Indicator lights ....................................................3-2
Speedometer......................................................3-2
Handlebar switches ............................................3-2
Clutch lever ........................................................3-4
Shift pedal ..........................................................3-4
Front brake lever ................................................ 3-4
Rear brake pedal................................................ 3-5
Fuel tank cap......................................................3-5
Fuel ....................................................................3-6
Fuel cock ............................................................3-6
Starter (choke) knob...........................................3-7
Seat ....................................................................3-8
Helmet holder .....................................................3-8
Rear shock absorber adjustment .......................3-9
Sidestand ...........................................................3-9
Sidestand/clutch switch operation check ......... 3-10PRE-OPERATION CHECKS ...............................4-1
Pre-operation check list......................................4-1
OPERATION AND IMPORTANT RIDING
POINTS................................................................5-1
Starting the engine .............................................5-1
Starting a warm engine ......................................5-3
Shifting ...............................................................5-4
Recommended shift points
(for Switzerland only) ......................................5-4
Tips for reducing fuel consumption ....................5-5
Engine break-in ..................................................5-5
Parking ...............................................................5-6
PERIODIC MAINTENANCE AND MINOR
REPAIR................................................................6-1
Tool kit................................................................6-1
Periodic maintenance and lubrication chart .......6-2
Panel removal and installation ...........................6-5
Panels A and B ..................................................6-5
Spark plug ..........................................................6-6
Engine oil ...........................................................6-8
Air filter .............................................................6-10
Carburetor adjustment .....................................6-11
Idle speed adjustment ......................................6-11
123
456
E_3mw.book Page 1 Monday, February 5, 2001 9:54 AM
Page 18 of 78

INSTRUMENT AND CONTROL FUNCTIONS
3-6
3
EAU01183
FuelMake sure there is sufficient fuel in the
tank. Fill the fuel tank to the bottom of
the filler tube as shown in the illustra-
tion.
EW000130
WARNING
@ Do not overfill the fuel tank. Avoid
spilling fuel on the hot engine. Do
not fill the fuel tank above the bot-
tom of the filler tube or it may over-
flow when the fuel heats up later and
expands. @
EAU00185
CAUTION:@ Always wipe off spilled fuel immedi-
ately with a dry and clean soft cloth.
Fuel may deteriorate painted surfac-
es or plastic parts. @
EAU00191
NOTE:@ If knocking or pinging occurs, use a dif-
ferent brand of gasoline or higher oc-
tane grade. @
EAU03050
Fuel cockThe fuel cock supplies fuel from the
tank to the carburetor while filtering it
also.
The fuel cock has three positions:
OFF
With the lever in this position, fuel will
not flow. Always return the lever to this
position when the engine is not run-
ning.
1. Filler tube
2. Fuel level
Recommended fuel:
Regular unleaded gasoline with a
research octane number of 91 or
higher.
Fuel tank capacity:
Total:
10.0 L
Reserve:
1.6 L
1. Arrow mark positioned over “OFF”OFF: closed position
E_3mw.book Page 6 Monday, February 5, 2001 9:54 AM
Page 32 of 78

PERIODIC MAINTENANCE AND MINOR REPAIR
6-2
6
EAU03686
Periodic maintenance and lubrication chart
NOTE:_ l
The annual checks must be performed every year, except if a kilometer-based maintenance is performed instead.
l
From 30,000 km, repeat the maintenance intervals starting from 6,000 km.
l
Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools, data and technical
skills.
_CP-03ENO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING (´1,000 km)
ANNUAL
CHECK
1 6 12 18 24
1
*Fuel line• Check fuel hoses for cracks or damage.ÖÖÖÖ Ö
2 Spark plug• Check condition.
• Clean and regap.ÖÖ
•Replace.ÖÖ
3*Valves• Check valve clearance.
• Adjust.ÖÖÖÖ
4*Timing chain• Check chain tension.
• Adjust.ÖÖÖÖ
5 Air filter element• Clean.ÖÖ
•Replace.ÖÖ
6*Battery• Check electrolyte level and specific gravity.
• Make sure that the breather hose is properly routed.ÖÖÖÖ Ö
7Clutch• Check operation.
• Adjust.ÖÖÖÖÖ
8*Front brake• Check operation, fluid level and vehicle for fluid leakage.
(See NOTE on page 6-4.)ÖÖÖÖÖ Ö
• Replace brake pads. Whenever worn to the limit
9*Rear brake• Check operation and adjust brake pedal free play.ÖÖÖÖÖ Ö
• Replace brake shoes. Whenever worn to the limit
E_3mw.book Page 2 Monday, February 5, 2001 9:54 AM
Page 70 of 78

8-1
8
EAU01038
8-SPECIFICATIONSSpecifications
Model SR125
Dimensions
Overall length 2,020 mm
Overall width 775 mm
Overall height 1,100 mm
Seat height 745 mm
Wheelbase 1,285 mm
Ground clearance 155 mm
Minimum turning radius 2,100 mm
Basic weight (with oil and full
fuel tank)
113 kg
Engine
Engine type Air-cooled 4-stroke, SOHC
Cylinder arrangement Forward-inclined single cylinder
Displacement 124 cm
3
Bore ´ Stroke 57.0 ´ 48.8 mm
Compression ratio 10:1
Starting system Electric starter
Lubrication system Wet sumpEngine oil
Ty p e
Recommended engine oil
classification API Service SE, SF, SG type or
higher
Quantity
Periodic oil change 1.0 L
With oil filter replacement 1.1 L
Total amount 1.3 L
Air filterWet type element
-20˚ -10˚ 0˚
10˚20˚ 30˚
40˚50˚C
SAE 10W/30
SAE 15W/40SAE 20W/40SAE 20W/50
SAE 10W/40
CAUTION:Be sure to use motor oils that do not contain anti-friction
modifiers. Passenger car motor oils (often labeled
“Energy Conserving”) contain anti-friction additives which
will cause clutch and/or starter clutch slippage, resulting in
reduced component life and poor engine performance.
E_3mw.book Page 1 Monday, February 5, 2001 9:54 AM