fuel YAMAHA TW125 2003 User Guide

5-4
OPERATION AND IMPORTANT RIDING POINTS
5
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Tips for reducing fuel
consumption
Fuel consumption depends largely on
your riding style. Consider the follow-
ing tips to reduce fuel consumption:
8Turn the starter (choke) off as
soon as possible.
8Shift up swiftly, and avoid high
engine speeds during accelera-
tion.
8Do not rev the engine while shift-
ing down, and avoid high engine
speeds with no load on the
engine.
8Turn the engine off instead of let-
ting it idle for an extended length
of time (e.g., in traffic jams, at
traffic lights or at railroad cross-
ings).
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Engine break-in
There is never a more important peri-
od in the life of your engine than the
period between 0 and 1,000 km. For
this reason, you should read the fol-
lowing material carefully.
Since the engine is brand new, do
not put an excessive load on it for the
first 1,000 km. The various parts in
the engine wear and polish them-
selves to the correct operating clear-
ances. During this period, prolonged
full-throttle operation or any condition
that might result in engine overheat-
ing must be avoided.
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0–500 km
Avoid prolonged operation above 1/3
throttle.
500–1,000 km
Avoid prolonged operation above 1/2
throttle.
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After 1,000 km of operation, the
engine oil must be changed, and
the oil filter element and the oil
strainer cleaned.
1,000 km and beyond
The vehicle can now be operated
normally.
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If any engine trouble should occur
during the engine break-in period,
immediately have a Yamaha dealer
check the vehicle.
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5-5
OPERATION AND IMPORTANT RIDING POINTS
5
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Parking
When parking, stop the engine,
remove the key from the main switch,
and then turn the fuel cock lever to
“OFF”.
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8Since the engine and exhaust
system can become very hot,
park in a place where pedestri-
ans or children are not likely
to touch them.
8Do not park on a slope or on
soft ground, otherwise the
motorcycle may overturn.
RES
ONFUEL
OFF
1
1. Arrow mark positioned over “OFF”
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6-2
PERIODIC MAINTENANCE AND MINOR REPAIR
6
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Periodic maintenance and lubrication chartPeriodic maintenance and lubrication chart
NOTE:
8The annual checks must be performed every year, except if a kilometer-based maintenance is performed instead.
8From 30,000 km, repeat the maintenance intervals starting from 6,000 km.
8Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools, data and
technical skills.
NO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING (× 1,000 km)
ANNUAL
CHECK
1 6 12 18 24
1
*Fuel line•Check fuel hoses and vacuum hose for cracks or damage.√√√√ √
2 Spark plug•Check condition.
•Clean and regap.√√
•Replace.√√
3
*Valves•Check valve clearance.
•Adjust.√√√√
4 Air filter element•Clean.√√
•Replace.√√
5 Clutch•Check operation.
•Adjust.√√√√√
6
*Front brake•Check operation, fluid level and vehicle for fluid leakage.
(See NOTE on page 6-4.)√√√√√ √
•Replace brake pads.Whenever worn to the limit
7
*Rear brake•Check operation and adjust brake pedal free play.√√√√√ √
•Replace brake shoes.Whenever worn to the limit
8
*Brake hose•Check for cracks or damage.√√√√ √
•Replace. (See NOTE on page 6-4.)Every 4 years
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6-16
PERIODIC MAINTENANCE AND MINOR REPAIR
6
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Adjusting the valve
clearance
The valve clearance changes with
use, resulting in improper air-fuel mix-
ture and/or engine noise. To prevent
this from occurring, the valve clear-
ance must be adjusted by a Yamaha
dealer at the intervals specified in the
periodic maintenance and lubrication
chart.
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Tires
To maximize the performance, dura-
bility, and safe operation of your
motorcycle, note the following points
regarding the specified tires.
Tire air pressure
The tire air pressure should be
checked and, if necessary, adjusted
before each ride.
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8The tire air pressure must be
checked and adjusted on cold
tires (i.e., when the tempera-
ture of the tires equals the
ambient temperature).
8The tire air pressure must be
adjusted in accordance with
the riding speed and with the
total weight of rider, passen-
ger, cargo, and accessories
approved for this model.
Tire air pressure
(measured on cold tires)
Load* Front Rear
Up to 90 kg150 kPa
(1.50 kgf/cm
2,
1.50 bar)150 kPa
(1.50 kgf/cm2,
1.50 bar)
90 kg–maximum150 kPa
(1.50 kgf/cm
2,
1.50 bar)175 kPa
(1.75 kgf/cm2,
1.75 bar)
Maximum load* 180 kg
* Total weight of rider, passenger, cargo and
accessories
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6-42
PERIODIC MAINTENANCE AND MINOR REPAIR
6
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After adjusting the brake pedal
free play, check the operation of
the brake light.
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Troubleshooting
Although Yamaha motorcycles
receive a thorough inspection before
shipment from the factory, trouble
may occur during operation. Any
problem in the fuel, compression, or
ignition systems, for example, can
cause poor starting and loss of
power.
The following troubleshooting chart
represents a quick and easy proce-
dure for checking these vital systems
yourself. However, should your
motorcycle require any repair, take it
to a Yamaha dealer, whose skilled
technicians have the necessary tools,
experience, and know-how to service
the motorcycle properly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look
like Yamaha parts, but they are often
inferior, have a shorter service life
and can lead to expensive repair
bills.
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6-43
PERIODIC MAINTENANCE AND MINOR REPAIR
6
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Troubleshooting chartEW000125
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Keep away open flames and do not smoke while checking or working on the fuel system.
Check the fuel level in
the fuel tank.
1. FuelThere is enough fuel.
There is no fuel.Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the electric starter.
2. CompressionThere is compression.
There is no compression.Check the ignition.
Have a Yamaha dealer
check the vehicle.
Remove the spark plug
and check the electrodes.
3. IgnitionWipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug.
Have a Yamaha dealer check the vehicle.
The engine does not start.
Have a Yamaha dealer
check the vehicle.
The engine does not start.
Check the battery.
Operate the electric starter.
4. BatteryThe engine turns over
quickly.
The engine turns over
slowly.The battery is good.
Check the battery lead connections,
and charge the battery if necessary.
Dry
WetOpen the throttle halfway and operate
the electric starter.
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7-2
MOTORCYCLE CARE AND STORAGE
78Do not use any harsh chemical
products on plastic parts. Be
sure to avoid using cloths or
sponges which have been in
contact with strong or abra-
sive cleaning products, sol-
vent or thinner, fuel (gasoline),
rust removers or inhibitors,
brake fluid, antifreeze or elec-
trolyte.
8Do not use high-pressure
washers or steam-jet cleaners
since they cause water seep-
age and deterioration in the
following areas: seals (of
wheel and swingarm bearings,
fork and brakes), electric com-
ponents (couplers, connec-
tors, instruments, switches
and lights), breather hoses
and vents.8For motorcycles equipped
with a windshield: Do not use
strong cleaners or hard
sponges as they will cause
dulling or scratching. Some
cleaning compounds for plas-
tic may leave scratches on the
windshield. Test the product
on a small hidden part of the
windshield to make sure that it
does not leave any marks. If
the windshield is scratched,
use a quality plastic polishing
compound after washing.After normal use
Remove dirt with warm water, a mild
detergent, and a soft, clean sponge,
and then rinse thoroughly with clean
water. Use a toothbrush or bottle-
brush for hard-to-reach areas.
Stubborn dirt and insects will come
off more easily if the area is covered
with a wet cloth for a few minutes
before cleaning.After riding in the rain, near the sea
or on salt-sprayed roads
Since sea salt or salt sprayed on
roads during winter are extremely
corrosive in combination with water,
carry out the following steps after
each ride in the rain, near the sea or
on salt-sprayed roads.
NOTE:
Salt sprayed on roads in the winter
may remain well into spring.
1. Clean the motorcycle with cold
water and a mild detergent, after
the engine has cooled down.
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Do not use warm water since it
increases the corrosive action of
the salt.
2. Apply a corrosion protection
spray on all metal, including
chrome- and nickel-plated, sur-
faces to prevent corrosion.
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7-4
MOTORCYCLE CARE AND STORAGE
7
Storage
Short-term
Always store your motorcycle in a
cool, dry place and, if necessary, pro-
tect it against dust with a porous
cover.
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8Storing the motorcycle in a
poorly ventilated room or cov-
ering it with a tarp, while it is
still wet, will allow water and
humidity to seep in and cause
rust.
8To prevent corrosion, avoid
damp cellars, stables (because
of the presence of ammonia)
and areas where strong chemi-
cals are stored.
Long-term
Before storing your motorcycle for
several months:
1. Follow all the instructions in the
“Care” section of this chapter.
2. For motorcycles equipped with a
fuel cock that has an “OFF” posi-
tion: Turn the fuel cock lever to
“OFF”.
3. Drain the carburetor float cham-
ber by loosening the drain bolt;
this will prevent fuel deposits
from building up. Pour the
drained fuel into the fuel tank.
4. Fill up the fuel tank and add fuel
stabilizer (if available) to prevent
the fuel tank from rusting and the
fuel from deteriorating.
5. Perform the following steps to
protect the cylinder, piston rings,
etc. from corrosion.a. Remove the spark plug cap
and spark plug.
b. Pour a teaspoonful of engine
oil into the spark plug bore.
c. Install the spark plug cap onto
the spark plug, and then place
the spark plug on the cylinder
head so that the electrodes
are grounded. (This will limit
sparking during the next step.)
d. Turn the engine over several
times with the starter. (This
will coat the cylinder wall with
oil.)
e. Remove the spark plug cap
from the spark plug, and then
install the spark plug and the
spark plug cap.
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To prevent damage or injury from
sparking, make sure to ground the
spark plug electrodes while turn-
ing the engine over.
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8-1
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SPECIFICATIONS
8
SpecificationsSpecifications
Model TW125
Dimensions
Overall length 2,135 mm
Overall width 820 mm
Overall height 1,120 mm
Seat height 820 mm
Wheelbase 1,350 mm
Ground clearance 255 mm
Minimum turning radius 2,100 mm
Basic weight (with oil and full
fuel tank)127 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
Type
Recommended engine oil
classification API Service SE, SF, SG type
or higher
cC
In order to prevent clutch slippage (since the engine oil also
lubricates the clutch), do not mix any chemical additives. Do
not use oils with a diesel specification of “CD” or oils of a
higher quality than specified. In addition, do not use oils
labeled “ENERGY CONSERVING II” or higher.
Capacity
Without oil filter element
removal 1.0 L
With oil filter element removal 1.1 L
Total amount (dry engine) 1.3 L
–10° 0° 10° 20° 30°
40°
SAE 10W/30
SAE 10W/40
SAE 20W/40
SAE 20W/50
–20°
SAE 15W/40 50°C
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8-2
SPECIFICATIONS
8
Air filterWet type element
Fuel
Type REGULAR UNLEADED
GASOLINE ONLY
Fuel tank capacity 7.0 L
Reserve amount 1.7 L
Carburetor
Manufacturer TEIKEI
Model ×quantity MV28 ×1
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 74/20 (3.700)
Secondary reduction system Chain drive
Secondary reduction ratio 3.643
Number of drive chain
sprocket teeth (rear/front) 51/14
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 25.83°
Trail 93 mm
Tires
Front
Type With tube
Size 130/80-18 M/C 66P
Manufacturer/ BRIDGESTONE/TW-203
model
Rear
Type With tube
Size 180/80-14 M/C 78P
Manufacturer/ BRIDGESTONE/TW-204
model
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