Page 28 of 78

OPERATION AND IMPORTANT RIDING POINTS
5-4
5
EAU00423
ShiftingThe transmission lets you control the
amount of power you have available at
a given speed for starting, accelerating,
climbing hills, etc. The use of the shift
pedal is shown in the illustration.
To shift into neutral, depress the shift
pedal repeatedly until it reaches the
end of its travel, then raise the pedal
slightly.
EC000048
CAUTION:@ l
Do not coast for long periods
with the engine off, and do not
tow the motorcycle a long dis-
tance. Even with gears in neu-
tral, the transmission is only
properly lubricated when the
engine is running. Inadequate
lubrication may damage the
transmission.
l
Always use the clutch when
changing gears. The engine,
transmission, and driveline are
not designed to withstand the
shock of forced shifting and can
be damaged by shifting without
using the clutch.
@
EAU02941
Recommended shift points
(for Switzerland only)The recommended shift points are
shown in the table below.CF-25ENOTE:@ When shifting two gears down from 4th
to 2nd, bring your motorcycle to a
speed of 35 km/h. @
1. Shift pedal
N. Neutral
Acceleration shift point
(km/h)
1st®2nd
2nd®3rd
3rd®4th
4th®5th23
36
50
60
E_3mw.book Page 4 Monday, February 5, 2001 9:54 AM
Page 29 of 78

OPERATION AND IMPORTANT RIDING POINTS
5-5
5
EAU00424
Tips for reducing fuel
consumptionYour motorcycle’s fuel consumption
depends to a large extent on your
riding style. The following tips can help
reduce fuel consumption:l
Warm up the engine before riding.
l
Turn off the starter (choke) as
soon as possible.
l
Shift up swiftly and avoid high en-
gine speeds during acceleration.
l
Do not double-clutch or rev the en-
gine while shifting down and avoid
high engine speeds with no load
on the engine.
l
Turn off the engine instead of let-
ting it idle for an extended length
of time, i.e. in traffic jams, at traffic
lights or railroad crossings.
EAU00436
Engine break-inThere is never a more important period
in the life of your motorcycle than the
period between zero and 1,000 km. For
this reason we ask that you carefully
read the following material. Because
the engine is brand new, you must not
put an excessive load on it for the first
1,000 km. The various parts in the en-
gine wear and polish themselves to the
correct operating clearances. During
this period, prolonged full throttle oper-
ation, or any condition which might re-
sult in excessive heating of the engine,
must be avoided.
E_3mw.book Page 5 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 39 of 78

PERIODIC MAINTENANCE AND MINOR REPAIR
6-9
6 4. Remove the filter cover screws,
drain bolt and the oil filter cover
and oil filter.
5. Clean the oil filter and strainer with
solvent. Replace if necessary.
6. Check the O-rings. If damaged, re-
place it.
7. Install the drain bolt, filter cover
screws and drain bolt. Then tight-
en to the specified torque.
NOTE:@ Make sure the O-ring is seated proper-
ly. @
EC000071*
CAUTION:@ Before reinstalling the oil drain bolt,
do not forget to install the O-ring,
compression spring, and oil strainer
in position. @8. Fill engine with oil. Install the oil fill-
er cap and tighten.
EC000066
CAUTION:@ l
Do not put in any chemical addi-
tives. Engine oil also lubricates
the clutch and additives could
cause clutch slippage.
l
Be sure no foreign material en-
ters the crankcase.
@9. Start the engine and warm up for a
few minutes. While warming up,
check for oil leakage. If oil leakage
is found, stop the engine immedi-
ately and check for the cause.
10. Stop the engine and check the oil
level.
1. Filter cover screw (´ 2)
2. Engine oil drain bolt B
Tightening torque:
Drain bolt A:
43 Nm (4.3 m·kg)
Filter cover screw:
7 Nm (0.7 m·kg)
Drain bolt B:
10 Nm (1.0 m·kg)
Recommended oil:
See page 8-1.
Oil quantity:
Total amount:
1.3 L
Periodic oil change:
1.0 L
With oil filter replacement:
1.1 L
E_3mw.book Page 9 Monday, February 5, 2001 9:54 AM
Page 46 of 78
PERIODIC MAINTENANCE AND MINOR REPAIR
6-16
6
EAU00692
Clutch lever free play
adjustmentThe clutch lever free play should be ad-
justed to 10 ~ 15 mm. If the free play is
incorrect, adjust as follows.
1. Loosen the locknut.
2. Turn the adjusting bolt at the
clutch lever in direction
a to in-
crease free play or in direction
b
to decrease free play.
3. Tighten the locknut.
NOTE:@ If proper adjustment cannot be ob-
tained or the clutch does not work cor-
rectly, ask a Yamaha dealer to inspect
the internal clutch mechanism. @
EAU00696
Front brake lever free play
adjustmentThe free play at the front brake lever
should be 2 ~ 5 mm.
1. Loosen the locknut.
2. Turn the adjusting bolt in
direction
a to increase free play
or in direction
b to decrease free
play.
3. After adjusting, tighten the locknut.
1. Locknut
2. Adjusting bolt
c. Free play
1. Locknut
2. Adjusting bolt
c. Free play
E_3mw.book Page 16 Monday, February 5, 2001 9:54 AM
Page 54 of 78
PERIODIC MAINTENANCE AND MINOR REPAIR
6-24
6
EAU02984
Brake and shift pedal
lubricationLubricate the pivoting parts.
EAU02985
Brake and clutch lever
lubricationLubricate the pivoting parts.
EAU02965
Center and sidestand
lubricationLubricate the pivoting and mating
joints.
Check to see that the center and side-
stand move up and down smoothly. Recommended lubricant:
Engine oil
Recommended lubricant:
Engine oil
Recommended lubricant:
Engine oil
E_3mw.book Page 24 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
Page 71 of 78
SPECIFICATIONS
8-2
8
Fuel
Type Regular unleaded gasoline
Fuel tank capacity 10.0 L
Fuel reserve amount 1.6 L
Carburetor
Type ´ quantity Y24P ´ 1
Manufacturer TEIKEI
Spark plug
Manufacturer/Type NGK / DR8EA
Gap 0.6 ~ 0.7 mm
Clutch typeWet, multiple-disc
Transmission
Primary reduction system Spur gear
Primary reduction ratio 3.318
Secondary reduction system Chain drive
Secondary reduction ratio 3.500
Number of drive chain
sprocket teeth (rear/front) 49/14
Transmission type Constant mesh 5-speed
Operation Left foot operationGear ratio
1st 2.250
2nd 1.476
3rd 1.125
4th 0.926
5th 0.793
Chassis
Frame type Diamond
Caster angle 26°45¢
Trail 90 mm
Tires
Front
Type With tube
Size 3.00-17 45P
Manufacturer/
model Inoue / 8F
Rear
Type With tube
Size 3.50-16 52P
Manufacturer/
model Inoue / 8RA
E_3mw.book Page 2 Monday, February 5, 2001 9:54 AM