2008 YAMAHA TTR50 torque

PERIODIC MAINTENANCE AND MINOR REPAIR
6-6
6 2. Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the
spark plug threads.
3. Install the spark plug with the
spark plug wrench, and then tight-
en it to the specified torque.
NOTE:
If 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.
4. Install the spark plug cap.
EAU39840
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.NOTE:Make sure that the motorcycle is posi-
tioned straight up when checking the oil
level. A slight tilt to the side can result ina 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.
NOTE:
The engine oil should be between theminimum 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.
Tightening torque:
Spark plug:
12.5 Nm (1.25 m·kgf, 9.0 ft·lbf)
1. Engine oil filler cap
2. Dipstick
3. Maximum level mark
4. Minimum level mark
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-7
6To 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.
3. Remove the engine oil filler cap
and drain bolt to drain the oil from
the crankcase.
4. Install the engine oil drain bolt, and
then tighten it to the specified
torque.5. Add the specified amount of the
recommended engine oil, and then
install and tighten the engine oil fill-
er cap.
CAUTION:
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.
1. Engine oil drain boltTightening torque:
Engine oil drain bolt:
20 Nm (2.0 m·kgf, 14 ft·lbf)
1
Recommended engine oil:
See page 8-1.
Oil change quantity:
0.80 L (0.85 US qt) (0.70 Imp.qt)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-10
6 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.3. Insert the tailpipe into the muffler,
and then install and tighten the
bolts to the specified torque.
NOTE:
Make sure to align the bolt holes wheninserting 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.CAUTION:
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.
1. Bolt
2. Tailpipe
1. Spark arrester
1
Tightening torque:
Tailpipe bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-15
63. Tighten the locknut to the specified
torque.
NOTE:
When tightening the locknut, hold the
clutch adjusting screw with a screwdriv-
er so that it does not turn together withthe locknut.
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).
WARNING
EWA10650
If proper adjustment cannot be ob-
tained as described, have a Yamahadealer make this adjustment.
Tightening torque:
Locknut:
6 Nm (0.6 m·kgf, 4.3 ft·lbf)
1. Brake lever free play
1
1. Brake lever free play adjusting nut
1
(a)
(b)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-18
6 2. To tighten the drive chain, turn the
adjusting nut at each end of the
swingarm in direction (a). To loos-
en the drive chain, turn the adjust-
ing nut at each end of the
swingarm in direction (b), and then
push the rear wheel forward.
NOTE:Using the alignment marks on each
side of the swingarm, make sure that
both adjusting nuts are in the same po-sition for proper wheel alignment.
CAUTION:
ECA10570
Improper drive chain slack will over-
load the engine as well as other vital
parts of the motorcycle and can lead
to chain slippage or breakage. To
prevent this from occurring, keep
the drive chain slack within thespecified limits.
3. Tighten both locknuts and the axle
nut to the specified torques.4. Adjust the brake pedal free play.
(See page 6-16.)
1. Brake pedal free play adjusting nut
2. Drive chain slack adjusting nut
3. Locknut
1
2
3
1. Axle nut
2. Locknut
3. Drive chain slack adjusting nut
4. Alignment marks
1(b) 4(a)
2
3
Tightening torques:
Locknut:
7.0 Nm (0.7 m·kgf, 5.1 ft·lbf)
Axle nut:
60 Nm (6.0 m·kgf, 43 ft·lbf)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-27
64. Lift the front wheel off the ground
according to the procedure on
page 6-25.
5. Remove the axle nut and washer.
6. Pull the wheel axle out, and then
remove the wheel.
EAU39801
To install the front wheel
1. Lift the wheel up between the fork
legs.
2. Insert the wheel axle from the
right-hand side.NOTE:Make sure that the slot in the brake
shoe plate fits over the retainer on thefork leg.3. Lower the front wheel so that it is
on the ground.
4. Install the washer and axle nut,
and then tighten the axle nut to the
specified torque.
5. Connect the brake cable to the
brake camshaft lever, and then in-
stall the brake cable free play ad-
justing nut on the brake cable.
6. Adjust the brake lever free play.
(See page 6-15.)7. While applying the front brake,
push down hard on the handlebar
several times to check for proper
fork operation.
8. Install each front fork leg guard by
installing the bolts.1. Wheel axle
1. Slot
2. RetainerTightening torque:
Axle nut:
35 Nm (3.5 m·kgf, 25 ft·lbf)
1
2
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-29
67. Remove the wheel.
EAU39781
To install the rear wheel
1. Install the drive chain onto the rear
sprocket, and then install the
wheel by inserting the wheel axle
from the right-hand side.NOTE:Make sure that the slot in the brake
shoe plate fits over the retainer on theswingarm.
2. Connect the brake rod to the brake
camshaft lever, and then install the
brake pedal free play adjusting nut
onto the brake rod.3. Adjust the drive chain slack. (See
page 6-17.)
4. Install the washer and axle nut,
and then lower the rear wheel so
that it is on the ground.
5. Tighten the axle nut to the speci-
fied torque.
6. Adjust the brake pedal free play.
(See page 6-16.)
EAU25850
Troubleshooting Although Yamaha motorcycles receive
a thorough inspection before shipment
from the factory, trouble may occur dur-
ing 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 procedure
for checking these vital systems your-
self. 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 inferi-
or, have a shorter service life and can
lead to expensive repair bills.
1. Slot
2. Retainer
Tightening torque:
Axle nut:
60 Nm (6.0 m·kgf, 43 ft·lbf)
U1P682E0.book Page 29 Wednesday, May 23, 2007 9:34 AM