maintenance YAMAHA TTR50 2011 User Guide

PERIODIC MAINTENANCE AND ADJUSTMENT
7-6
7
EAU19613
Checking the spark plug The spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic mainte-
nance and lubrication chart. In addition,
the condition of the spark plug can re-
veal the condition of the engine.
To remove the spark plug
1. Remove the spark plug cap.
2. Remove the spark plug as shown,
with a spark plug wrench available
at a Yamaha dealer.To check the spark plug
1. Check that the porcelain insulator
around the center electrode of the
spark plug is a medium-to-light tan
(the ideal color when the vehicle is
ridden normally).
TIPIf the spark plug shows a distinctly dif-
ferent color, the engine could be oper-
ating improperly. Do not attempt to
diagnose such problems yourself. In-
stead, have a Yamaha dealer check
the vehicle.
2. Check the spark plug for electrode
erosion and excessive carbon or
other deposits, and replace it if
necessary.
3. Measure the spark plug gap with a
wire thickness gauge and, if nec-
essary, adjust the gap to specifica-
tion.
1. Spark plug cap
1. Spark plug wrench
Specified spark plug:
NGK/CR7HSA
1. Spark plug gap
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-7
7To install the spark plug
1. Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the
spark plug threads.
2. Install the spark plug with the
spark plug wrench, and then tight-
en it to the specified torque.
TIPIf a torque wrench is not available when
installing a spark plug, a good estimate
of the correct torque is 1/4–1/2 turn
past finger tight. However, the spark
plug should be tightened to the speci-
fied torque as soon as possible.3. Install the spark plug cap.
EAU49930
Engine oil The engine oil level should be checked
before each ride. In addition, the oil
must be changed at the intervals spec-
ified in the periodic maintenance and
lubrication chart.
To check the engine oil level
1. Place the motorcycle on a level
surface and hold it in an upright po-
sition. A slight tilt to the side can re-
sult in a false reading.
2. Start the engine, warm it up for
several minutes, and then turn it
off.
3. Wait a few minutes until the oil set-
tles, remove the oil filler cap, wipe
the dipstick clean, insert it back
into the oil filler hole (without
screwing it in), and then remove it
again to check the oil level.TIPThe engine oil should be between the
minimum and maximum level marks.
4. If the engine oil is at or below the
minimum level mark, add sufficient
oil of the recommended type to
raise it to the correct level.
5. Insert the dipstick into the oil filler
hole, and then tighten the oil filler
cap.
To change the engine oil
1. Start the engine, warm it up for
several minutes, and then turn it
off.
2. Place an oil pan under the engine
to collect the used oil.
Tightening torque:
Spark plug:
13 Nm (1.3 m·kgf, 9.4 ft·lbf)
1. Engine oil filler cap
2. Engine oil dipstick
3. Maximum level mark
4. Minimum level mark
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-8
7 3. Remove the engine oil filler cap,
the drain bolt and the gasket to
drain the oil from the crankcase.
4. Install a new gasket and the en-
gine oil drain bolt, and then tighten
the bolt to the specified torque.
5. Refill with the specified amount of
the recommended engine oil, and
then install and tighten the engine
oil filler cap.
NOTICE
ECA11620


In order to prevent clutch slip-
page (since the engine oil also
lubricates the clutch), do not
mix any chemical additives. Do
not use oils with a diesel speci-
fication of “CD” or oils of a high-
er quality than specified. In
addition, do not use oils labeled
“ENERGY CONSERVING II” or
higher.


Make sure that no foreign mate-
rial enters the crankcase.
6. Start the engine, and then let it idle
for several minutes while checking
it for oil leakage. If oil is leaking, im-
mediately turn the engine off and
check for the cause.
7. Turn the engine off, and then
check the oil level and correct it if
necessary.
EAU39834
Cleaning the air filter element The air filter element should be cleaned
as follows at the intervals specified in
the periodic maintenance and lubrica-
tion chart. Clean or, if necessary, re-
place the air filter element more
frequently if you are riding in unusually
wet or dusty areas.
To clean the air filter element
1. Remove the air filter case cover by
removing the screws.
2. Pull the sponge material and the
air filter mesh out.
1. Engine oil drain bolt
2. GasketTightening torque:
Engine oil drain bolt:
20 Nm (2.0 m·kgf, 14 ft·lbf)
12
Recommended engine oil:
See page 9-1.
Oil change quantity:
0.80 L (0.85 US qt, 0.70 Imp.qt)
1. Screw
2. Air filter case cover
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-9
7
3. Clean the mesh with solvent, and
then wipe the solvent off.
4. Clean the sponge material with
solvent, and then squeeze the re-
maining solvent out. WARNING!
Use only a dedicated parts
cleaning solvent. To avoid therisk of fire or explosion, do not
use gasoline or solvents with a
low flash point.
[EWA10431]
NOTICE:
To avoid damaging the foam
material, handle it gently and
carefully, and do not twist or
wring it.
[ECA10511]
5. Apply oil of the recommended type
to the entire surface of the sponge
material, and then squeeze the ex-
cess oil out.TIPThe sponge material should be wet but
not dripping.
6. Insert the mesh and the sponge
material into the air filter case.
NOTICE: Make sure that the
mesh and the sponge material
are properly seated in the air fil-
ter case. The engine should
never be operated without the
mesh and the sponge material
installed, otherwise the pis-
ton(s) and/or cylinder(s) may
become excessively worn.
[ECA15572]
7. Install the air filter case cover by in-
stalling the screws.
To clean the air filter check hose
1. Check the hose at the bottom of
the air filter case for accumulated
dirt or water.
1. Sponge material
1. Air filter mesh
Recommended oil:
Yamaha foam air filter oil or other
quality foam air filter oil
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-10
7 2. If dirt or water is visible, remove
the hose, clean it, and then install
it.
EAU40421
Cleaning the spark arrester The spark arrester should be cleaned
at the intervals specified in the periodic
maintenance and lubrication chart.
WARNING
EWA10980


Always let the exhaust system
cool prior to touching exhaust
components.


Do not start the engine when
cleaning the exhaust system.
TIPMake sure to select a well-ventilated
area free of combustible materials to
clean the spark arrester.1. Remove the tailpipe by removing
the bolts, and then pulling it out of
the muffler.2. Tap the tailpipe lightly, and then
use a wire brush to remove any
carbon deposits from the spark ar-
rester portion of the tailpipe and in-
side of the tailpipe housing.
1. Air filter check hose
1. Bolt
2. Tailpipe
1. Spark arrester
1
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-11
73. Insert the tailpipe into the muffler,
and then install and tighten the
bolts to the specified torque.
TIPMake sure to align the bolt holes when
inserting the tailpipe.
EAU39930
Adjusting the carburetor The carburetor is an important part of
the engine and requires very sophisti-
cated adjustment. Therefore, most car-
buretor adjustments should be left to a
Yamaha dealer, who has the neces-
sary professional knowledge and expe-
rience. The adjustment described in the
following section, however, may be ser-
viced by the owner as part of routine
maintenance.NOTICE
ECA10550
The carburetor has been set and ex-
tensively tested at the Yamaha fac-
tory. Changing these settings
without sufficient technical knowl-
edge may result in poor perfor-
mance of or damage to the engine.
EAU21362
Adjusting the engine idling
speed The engine idling speed must be
checked and, if necessary, adjusted as
follows at the intervals specified in the
periodic maintenance and lubrication
chart.TIPA diagnostic tachometer is needed to
make this adjustment.1. Attach the tachometer to the spark
plug lead.
2. Start the engine and warm it up for
several minutes at 1000–2000
r/min while occasionally revving it
to 4000–5000 r/min.TIPThe engine is warm when it quickly re-
sponds to the throttle.3. Check the engine idling speed
and, if necessary, adjust it to spec-
ification by turning the throttle stop
screw. To increase the engine
idling speed, turn the screw in di-
Tightening torque:
Tailpipe bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-12
7 rection (a). To decrease the en-
gine idling speed, turn the screw in
direction (b).
TIPIf the specified idling speed cannot be
obtained as described above, have a
Yamaha dealer make the adjustment.
EAU21372
Adjusting the throttle cable
free play The throttle cable free play should mea-
sure 3.0–5.0 mm (0.12–0.20 in) at the
throttle grip. Periodically check the
throttle cable free play and, if neces-
sary, adjust it as follows.TIPThe engine idling speed must be cor-
rectly adjusted before checking and ad-
justing the throttle cable free play.1. Loosen the locknut.2. To increase the throttle cable free
play, turn the adjusting nut in direc-
tion (a). To decrease the throttle
cable free play, turn the adjusting
nut in direction (b).
3. Tighten the locknut.
1. Throttle stop screwEngine idling speed:
1600–1800 r/min
1
(a) (b)
1. Throttle cable free play
1. Locknut
2. Throttle cable free play adjusting nut
2 (a)
(b) 1
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-13
7
EAU21401
Valve clearance The valve clearance changes with use,
resulting in improper air-fuel mixture
and/or engine noise. To prevent this
from occurring, the valve clearance
must be adjusted by a Yamaha dealer
at the intervals specified in the periodic
maintenance and lubrication chart.
EAU39824
Tires To maximize the performance, durabil-
ity, and safe operation of your motorcy-
cle, 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.
WARNING
EWA15370
Operation of this vehicle with im-
proper tire pressure may cause se-
vere injury or death from loss of
control.
The tire air pressure must be
checked and adjusted on cold tires
(i.e., when the temperature of the
tires equals the ambient tempera-
ture).
Tire inspection
The tires must be checked before each
ride. If the center tread depth reaches
the specified limit, if the tire has a nail or
glass fragments in it, or if the sidewall is
cracked, have a Yamaha dealer re-
place the tire immediately.
Tire information
This motorcycle is equipped with spoke
wheels and tube tires.
Standard tire air pressure:
Fr o nt :
100 kPa (1.00 kgf/cm², 15 psi)
Rear:
100 kPa (1.00 kgf/cm², 15 psi)
1. Tire sidewall
2. Tire tread depthMinimum tire tread depth (front and
rear):
4.0 mm (0.16 in)
12
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-14
7
WARNING
EWA10461
The front and rear tires should be of
the same make and design, other-
wise the handling characteristics of
the vehicle may be different, which
could lead to an accident.After extensive tests, only the tires list-
ed below have been approved for this
model by Yamaha Motor Co., Ltd.
WARNING
EWA15541


Have a Yamaha dealer replace
excessively worn tires. Operat-
ing the motorcycle with exces-
sively worn tires decreases
riding stability and can lead to
loss of control.


The replacement of all wheel-
and brake-related parts, includ-
ing the tires, should be left to a
Yamaha dealer, who has the
necessary professional knowl-
edge and experience.


It is not recommended to patch
a punctured tube. If unavoid-
able, however, patch the tube
very carefully and replace it as
soon as possible with a high-
quality product.


Ride conservatively after
changing a tire since the tire
must seat itself on the rim prop-
erly. Failure to allow proper
seating may cause tire failure,
which may result in damage to
the motorcycle and injury to the
rider.
EAU21942
Spoke wheels
WARNING
EWA10610
The wheels on this model are not de-
signed for use with tubeless tires.
Do not attempt to use tubeless tires
on this model.To maximize the performance, durabil-
ity, and safe operation of your motorcy-
cle, note the following points regarding
the specified wheels.

The wheel rims should be checked
for cracks, bends or warpage, and
the spokes for looseness or dam-
age before each ride. If any dam-
age is found, have a Yamaha
dealer replace the wheel. Do not
attempt even the smallest repair to
the wheel. A deformed or cracked
wheel must be replaced.


The wheel should be balanced
whenever either the tire or wheel
has been changed or replaced. An
unbalanced wheel can result in
poor performance, adverse han-
dling characteristics, and a short-
ened tire life.
Front tire:
Size:
2.50-10 4PR
Manufacturer/model:
CHENG SHIN/KNOBBY
Rear tire:
Size:
2.50-10 4PR
Manufacturer/model:
CHENG SHIN/KNOBBY
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-15
7
EAU46251
Adjusting the clutch free play The clutch free play must be checked
and, if necessary, adjusted as follows
at the intervals specified in the periodic
maintenance and lubrication chart.
1. Remove the clutch adjusting
screw cover by removing the
screws.
2. Loosen the locknut.
3. Slowly turn the clutch adjusting
screw in direction (a) until resis-
tance is felt, and then turn it 1/8
turn in direction (b).4. Tighten the locknut to the specified
torque.
TIPWhen tightening the locknut, hold the
clutch adjusting screw with a screwdriv-
er so that it does not turn together with
the locknut.5. Install the clutch adjusting screw
cover by installing the screws.
EAU22130
Adjusting the brake lever free
play The brake lever free play should mea-
sure 10.0–20.0 mm (0.39–0.79 in) as
shown. Periodically check the brake le-
ver free play and, if necessary, adjust it
as follows.
To increase the brake lever free play,
turn the adjusting nut at the brake shoe
plate in direction (a). To decrease the
brake lever free play, turn the adjusting
nut in direction (b).
1. Screw
2. Clutch adjusting screw cover
1. Locknut
2. Clutch adjusting screwTightening torque:
Locknut:
6 Nm (0.6 m·kgf, 4.3 ft·lbf)
1. Brake lever free play
1
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