engine YAMAHA TW125 2002 Owner's Guide

6-37
PERIODIC MAINTENANCE AND MINOR REPAIR
6 2. Remove the defective bulb by
pushing it in and turning it coun-
terclockwise.
3. Insert a new bulb into the socket,
push it in, and then turn it clock-
wise until it stops.
4. Install the lens by installing the
screws.
EC000108
cCDo not overtighten the screws,
otherwise the lens may break.
1
1. Bulb
To service the rear wheel
Raise the rear wheel off the ground
by using a motorcycle stand or, if a
motorcycle stand is not available, by
placing a jack either under each side
of the frame in front of the rear wheel
or under each side of the swingarm.
EAU01579
Supporting the motorcycleSince this model is not equipped with
a centerstand, follow these precau-
tions when removing the front and
rear wheel or performing other main-
tenance requiring the motorcycle to
stand upright. Check that the motor-
cycle is in a stable and level position
before starting any maintenance. A
strong wooden box can be placed
under the engine for added stability.
To service the front wheel
1. Stabilize the rear of the motorcy-
cle by using a motorcycle stand
or, if an additional motorcycle
stand is not available, by placing
a jack under the frame in front of
the rear wheel.
2. Raise the front wheel off the
ground by using a motorcycle
stand.
5RS-9-E0 (TW125) 7/30/01 6:03 PM Page 67

6-43
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU01397
Troubleshooting chart
EW000125
wKeep away open flames and do not smoke while checking or working on the fuel system.Check the fuel level in
the fuel tank.1. Fuel
There 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. Compression
There 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. Ignition
Wipe 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. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and charge the battery if necessary.
DryWet
Open the throttle halfway and operate
the electric starter.
5RS-9-E0 (TW125) 7/30/01 6:03 PM Page 73

7-1
EAU03521
MOTORCYCLE CARE AND STORAGE
7
CareWhile the open design of a motorcy-
cle reveals the attractiveness of the
technology, it also makes it more vul-
nerable. Rust and corrosion can
develop even if high-quality compo-
nents are used. A rusty exhaust pipe
may go unnoticed on a car, however,
it detracts from the overall appear-
ance of a motorcycle. Frequent and
proper care does not only comply
with the terms of the warranty, but it
will also keep your motorcycle looking
good, extend its life and optimize its
performance.Before cleaning
1. Cover the muffler outlet with a
plastic bag after the engine has
cooled down.
2. Make sure that all caps and cov-
ers as well as all electrical cou-
plers and connectors, including
the spark plug cap, are tightly
installed.
3. Remove extremely stubborn dirt,
like oil burnt onto the crankcase,
with a degreasing agent and a
brush, but never apply such
products onto seals, gaskets,
sprockets, the drive chain and
wheel axles. Always rinse the dirt
and degreaser off with water.Cleaning
ECA00010
cC8Avoid using strong acidic
wheel cleaners, especially on
spoked wheels. If such prod-
ucts are used on hard-to-
remove dirt, do not leave the
cleaner on the affected area
any longer than instructed.
Also, thoroughly rinse the area
off with water, immediately dry
it, and then apply a corrosion
protection spray.
8Improper cleaning can damage
windshields, cowlings, panels
and other plastic parts. Use
only a soft, clean cloth or
sponge with mild detergent
and water to clean plastic.
5RS-9-E0 (TW125) 7/30/01 6:03 PM Page 74

7-2
MOTORCYCLE CARE AND STORAGE
7 8Do 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 useRemove 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 roadsSince 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.
ECA00012
cCDo 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.
5RS-9-E0 (TW125) 7/30/01 6:03 PM Page 75

7-4
MOTORCYCLE CARE AND STORAGE
7
StorageShort-term
Always store your motorcycle in a
cool, dry place and, if necessary, pro-
tect it against dust with a porous
cover.
ECA00014
cC8Storing 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.
EWA00003
wTo prevent damage or injury from
sparking, make sure to ground the
spark plug electrodes while turn-
ing the engine over.
5RS-9-E0 (TW125) 7/30/01 6:03 PM Page 77

8-1
EAU01038
SPECIFICATIONS
8
Specifications
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
cCBe sure to use motor oils that do not contain anti-friction
modifiers. Passenger car motor oils (often labeled “ENERGY
CONSERVING II”) contain anti-friction additives which will
cause clutch and/or starter clutch slippage, resulting in
reduced component life and poor engine performance.
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
5RS-9-E0 (TW125) 7/30/01 6:03 PM Page 79