2008 YAMAHA TTR50 engine

OPERATION AND IMPORTANT RIDING POINTS
5-3
5
CAUTION:
ECA15460
Always close the throttle before
shifting gears, otherwise damage to
the engine and drive train may re-sult.
3. Open the throttle gradually.
4. Once the motorcycle has reached
a speed high enough to change
gears, close the throttle.
5. Shift into second gear and release
the shift pedal.
6. Open the throttle gradually.
7. Follow the same procedure when
shifting to the next higher gear.
EAU16710
To decelerate
1. Close the throttle and apply both
the front and the rear brakes to
slow the motorcycle.
2. Downshift through the gears and
shift the transmission into the neu-
tral position when the motorcycle
is almost completely stopped.
EAU39920
Engine break-in There is never a more important period
in the life of your engine than the first 5
hours of riding. It is also important to ac-
custom the rider to the motorcycle dur-
ing this time. Please read the following
information carefully.
Since the engine is brand new, do not
put an excessive load on it for the first 5
hours of operation. The various parts in
the engine wear and polish themselves
to the correct operating clearances.
During this period, prolonged full-throt-
tle operation or any condition that might
result in engine overheating must be
avoided. However, momentary full-
throttle operation under load (i.e., two
to three seconds maximum) does not
harm the engine. Each full-throttle ac-
celeration should be followed with a
substantial rest period for the engine.
To allow the engine to cool down from
the temporary buildup of heat, cruise at
a lower engine speed.
After the first 5 hours of operation, thor-
oughly check the motorcycle for loose
parts, oil leakage and any other prob-
lems. Be sure to inspect and make ad-justments thoroughly, especially cable
and drive chain slack and loose
spokes. In addition, check all fittings
and fasteners for looseness, and tight-
en if necessary.
CAUTION:
ECA10270
If any engine trouble should occur
during the engine break-in period,
immediately have a Yamaha dealercheck the vehicle.
U1P682E0.book Page 3 Wednesday, May 23, 2007 9:34 AM

OPERATION AND IMPORTANT RIDING POINTS
5-4
5
EAU17170
Parking When parking, stop the engine, remove
the key from the main switch, and then
turn the fuel cock lever to “OFF”.
WARNING
EWA10310


Since the engine and exhaust
system can become very hot,
park in a place where pedestri-
ans or children are not likely to
touch them.


Do not park on a slope or on soft
ground, otherwise the vehiclemay overturn.
U1P682E0.book Page 4 Wednesday, May 23, 2007 9:34 AM

PERIODIC MAINTENANCE AND MINOR REPAIR
6-2
6
EAU39943
Periodic maintenance chart for the emission control system NOTE:

From 7000 km (4200 mi) or 18 months, repeat the maintenance intervals starting from 3000 km (1800 mi) or 6 months.


Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools, data and technicalskills.
No. ITEM CHECKS AND MAINTENANCE JOBSINITIAL ODOMETER READINGS
1000 km
(600 mi) or
1 month or
30 hours3000 km
(1800 mi) or
6 months or
90 hours5000 km
(3000 mi) or
12 months or
150 hours
1*Fuel lineCheck fuel hoses for cracks or damage.
Replace if necessary.√√
2 Spark plugCheck condition.
Adjust gap and clean.√√
3*Valve clearanceCheck and adjust valve clearance when engine is cold.√
4*Air filter elementClean with solvent.
Replace if necessary.√√
5*Crankcase breather sys-
temCheck ventilation hose for cracks or damage and drain
any deposits.
Replace if necessary.√√√
6*CarburetorCheck engine idling speed and starter operation.
Adjust if necessary.√√√
7 Exhaust systemCheck for leakage.
Tighten if necessary.
Replace gasket(s) if necessary.√√
8 Engine oilChange (warm engine before draining).√√√
U1P682E0.book Page 2 Wednesday, May 23, 2007 9:34 AM

PERIODIC MAINTENANCE AND MINOR REPAIR
6-4
6
EAU40000
NOTE:The air filter needs more frequent service if you are riding in unusually wet or dusty areas.10*Chassis fastenersCheck all chassis fitting and fasteners.
Correct if necessary.√√√
11 Brake lever pivot shaftApply lithium-soap-based grease (all-purpose grease)
lightly.√√
12 Brake pedal pivot shaftApply lithium-soap-based grease (all-purpose grease)
lightly.√√
13 Sidestand pivotCheck operation.
Apply lithium-soap-based grease (all-purpose grease)
lightly.√√
14*Spark arresterClean.√
15*Front forkCheck operation and for grease leakage.
Replace if necessary.√√
16*Shock absorber assem-
blyCheck operation and for oil leakage.
Replace if necessary.√
17*Control cablesApply Yamaha chain and cable lube or engine oil 10W-30
thoroughly.√√√
18*Throttle grip housing and
cableCheck operation and free play.
Adjust the throttle cable free play if necessary.
Lubricate the throttle grip housing and cable.√√√ No. ITEM CHECKS AND MAINTENANCE JOBSINITIAL ODOMETER READINGS
1000 km
(600 mi) or
1 month or
30 hours3000 km
(1800 mi) or
6 months or
90 hours5000 km
(3000 mi) or
12 months or
150 hours
U1P682E0.book Page 4 Wednesday, May 23, 2007 9:34 AM

PERIODIC MAINTENANCE AND MINOR REPAIR
6-5
6
EAU19612
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).
NOTE:
If 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 checkthe vehicle.2. Check the spark plug for electrode
erosion and excessive carbon or
other deposits, and replace it if
necessary.
To install the spark plug
1. 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/CR7HSA1. Spark plug gapSpark plug gap:
0.6–0.7 mm (0.024–0.028 in)
U1P682E0.book Page 5 Wednesday, May 23, 2007 9:34 AM

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
U1P682E0.book Page 6 Wednesday, May 23, 2007 9:34 AM

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)
U1P682E0.book Page 7 Wednesday, May 23, 2007 9:34 AM

PERIODIC MAINTENANCE AND MINOR REPAIR
6-9
6
NOTE:The sponge material should be wet butnot dripping.
6. Insert the mesh and the sponge
material into the air filter case.CAUTION:
ECA15571


Make sure that the mesh and the
sponge material are properly
seated in the air filter case.


The engine should never be op-
erated without the mesh and the
sponge material installed, oth-
erwise the piston(s) and/or cyl-
inder(s) may becomeexcessively worn.
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.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 whencleaning the exhaust system.
NOTE:Make sure to select a well-ventilated
area free of combustible materials toclean the spark arrester.
1. Remove the tailpipe by removing
the bolts, and then pulling it out of
the muffler.
Recommended oil:
Yamaha foam air filter oil or other
quality foam air filter oil
1. Air filter check hose
U1P682E0.book Page 9 Wednesday, May 23, 2007 9:34 AM