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Periodic maintenance an d a djustment
7-12
7 2. If dirt or water is visible, remove
the hoses, clean them, and then
reinstall them.
EAU40422
Cleanin g the spark arrester
The spark arrester should be cleaned
at the intervals specified in the periodic
maintenance and lubrication chart.
WARNING
EWA10981
Always let the exhaust system
cool prior to touchin g exhaust
components.
Do not start the en gine when
cleanin g the exhaust system.
TIP
Make 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
arrester portion of the tailpipe and
inside of the tailpipe housing.
1. Air filter check hose
1
1. Tailpipe
2. Tailpipe bolt
21
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Periodic maintenance an d a djustment
7-13
7
3. Insert the tailpipe into the muffler,
and then install and tighten the
bolts to the specified torque.
TIP
Make sure to align the bolt holes when
inserting the tailpipe.
EAU39931
Adjustin g the car buretor
The carburetor is an important part of
the engine and requires very sophisti-
cated adjustment. Therefore, most
carburetor adjustments should be left
to a Yamaha dealer, who has the nec-
essary professional knowledge and ex-
perience. The adjustment described in
the following section, however, may be
serviced by the owner as part of rou-
tine maintenance.
NOTICE
ECA10551
The car buretor has b een set and ex-
tensively teste d at the Yamaha fac-
tory. Chan gin g these settin gs
without sufficient technical knowl-
e dge may result in poor perfor-
mance of or d amage to the en gine.
1. Spark arrester
Ti ghtening torque:
Tailpipe bolt: 10 N·m (1.0 kgf·m, 7.4 lb·ft)
1
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Periodic maintenance an d a djustment
7-14
7
EAU21363
A djustin g the en gine i dlin g
spee d
The engine idling speed must be
checked and, if necessary, adjusted as
follows at the intervals specified in the
periodic maintenance and lubrication
chart.
TIP
A 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.
TIP
The engine is warm when it quickly re-
sponds to the throttle.
3. Check the engine idling speedand, if necessary, adjust it to
specification by turning the throt-
tle stop screw. To increase the en-
gine idling speed, turn the screw in
direction (a). To decrease the en-
gine idling speed, turn the screw in
direction (b).
TIP
If the specified idling speed cannot be
obtained as described above, have a
Yamaha dealer make the adjustment.
1. Throttle stop screw
(a) (b)
1
En gine i dlin g spee d:
1600–1800 r/min
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Periodic maintenance an d a djustment
7-15
7
EAU21386
Checkin g the throttle grip free
play
Measure the throttle grip free play as
shown.
Periodically check the throttle grip free
play and, if necessary, have a Yamaha
dealer adjust it.
EAU21403
Valve clearance
The valves are an important engine
component, and since valve clearance
changes with use, they must be
checked and adjusted at the intervals
specified in the periodic maintenance
chart. Unadjusted valves can result in
improper air-fuel mixture, engine
noise, and eventually engine damage.
To prevent this from occurring, have
your Yamaha dealer check and adjust
the valve clearance at regular intervals.
TIP
This service must be performed when
the engine is cold.1. Throttle grip free play
Throttle g rip free play:
4.0–6.0 mm (0.16–0.24 in)
1
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Periodic maintenance an d a djustment
7-16
7
EAUW3500
Tires
Tires are the only contact between the
vehicle and the road. Safety in all con-
ditions of riding depends on a relatively
small area of road contact. Therefore, it
is essential to maintain the tires in good
condition at all times and replace them
at the appropriate time with the speci-
fied tires.
Tire air pressure
The tire air pressure should be
checked and, if necessary, adjusted
before each ride.
WARNING
EWA10442
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 a djuste d on col d
tires (i.e., when the temperature
of the tires equals the am bient
temperature).
The tire air pressure must be
a d juste d in accor dance with the
ri din g speed and with the total
wei ght of ri der, car go, an d ac-
cessories approved for this
mo del.
WARNING
EWA10512
Never overloa d your vehicle. Opera-
tion of an overloa ded vehicle coul d
cause an acci dent.
Tire inspection
The tires must be checked before each
ride. If the center tread depth reaches
the specified limit (minimum tire tread
depth), 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 model is equipped with tube tires.
Tires age, even if they have not been
used or have only been used occasion-
ally. Cracking of the tread and sidewall
rubber, sometimes accompanied by
carcass deformation, is an evidence of
ageing. Old and aged tires shall be
checked by tire specialists to ascertain
their suitability for further use.
Stan dar d tire pressure:
Front: 100 kPa (1.00 kgf/cm², 15 psi)
Rear:
100 kPa (1.00 kgf/cm², 15 psi)
1. Tire sidewall
2. Tire tread depth
Minimum tire trea d d epth (front an d
rear): 4.0 mm (0.16 in)
1
2
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Periodic maintenance an d a djustment
7-17
7
WARNING
EWA10462
The front an d rear tires shoul d b e of
the same make an d d esi gn, other-
wise the han dlin g characteristics of
the vehicle may be different, which
coul d lea d to an acci dent.
After extensive tests, only the tires list-
ed below have been approved for this
model by Yamaha.
WARNING
EWA14391
Have a Yamaha dealer replace
excessively worn tires. Operat-
in g the motorcycle with exces-
sively worn tires decreases
ri din g sta bility an d can lead to
loss of control.
The replacement of all wheel-
and b rake-related parts, includ-
in g the tires, shoul d b e left to a
Yamaha dealer, who has the
necessary professional knowl-
e dge an d experience.
It is not recommen ded to patch
a puncture d tu be. If unavoid -
a b le, however, patch the tu be
very carefully an d replace it as
soon as possi ble with a hi gh-
quality prod uct.
EAU21944
Spoke wheels
WARNING
EWA10611
The wheels on this mod el are not
d esi gne d for use with tu beless tires.
Do not attempt to use tu beless tires
on this mo del.
To maximize the performance, durabil-
ity, and safe operation of your motor-
cycle, note the following points
regarding the specified wheels.
The wheel rims should be
checked for cracks, bends, warp-
age or other damage, and the
spokes for looseness or damage
before each ride. If any damage is
found, have a Yamaha dealer re-
place 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:
2.50-14 4PR
Manufacturer/model: CHENG SHIN/C-803
Rear tire: Size:3.00-12 4PR
Manufacturer/model: CHENG SHIN/C-803
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Periodic maintenance an d a djustment
7-18
7
EAU44664
A djustin g 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. Loosen the locknut.
2. Slowly turn the clutch adjusting screw in direction (a) until resis-
tance is felt, and then turn it 1/8
turn in direction (b).
3. Tighten the locknut to the speci- fied torque.
TIP
When tightening the locknut, hold the
clutch adjusting screw with a screw-
driver so that it does not turn together
with the locknut.
EAU44886
Adjustin g the brake lever free
play
Measure the brake lever free play as
shown.
Periodically check the brake lever free
play and, if necessary, adjust it as fol-
lows.
1. Slide the rubber cover back.
2. Loosen the locknut at the brake le- ver.
3. To increase the brake lever free play, turn the brake lever free play
adjusting bolt in direction (a). To
decrease the brake lever free play,
turn the adjusting bolt in direction
(b).
TIP
Skip steps 4–7 if the specified brake le-
ver free play could be obtained as de-
scribed above.
4. Fully turn the adjusting bolt at thebrake lever in direction (a) to loos-
en the brake cable.
1. Locknut
2. Clutch adjusting screw
Tightenin g torque:
Locknut:
8 N·m (0.8 kgf·m, 5.9 lb·ft)
1 2
(a)(b)1. Rubber cover
2. Brake lever free play adjusting bolt
3. Locknut
4. Brake lever free play
Brake lever free play:
10.0–20.0 mm (0.39–0.79 in)
3
21
(b)
(a) 4
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Periodic maintenance an d a djustment
7-19
7
5. Loosen the locknut at the brake
shoe plate.
6. To increase the brake lever free play, turn the adjusting bolt at the
brake shoe plate in direction (a).
To decrease the brake lever free
play, turn the adjusting bolt in di-
rection (b).
7. Tighten the locknut at the brake shoe plate.
8. Tighten the locknut at the brake lever, and then slide the rubber
cover to its original position.
EAU44673
Adjustin g the brake pe dal free
play
Measure the brake pedal free play at
the brake pedal end as shown.
Periodically check the brake pedal free
play and, if necessary, adjust it as fol-
lows.
To increase the brake pedal free play,
turn the brake pedal free play adjusting
nut at the brake rod in direction (a). To
decrease the brake pedal free play,
turn the adjusting nut in direction (b).
WARNING
EWA14821
After a djustin g the d rive chain
slack or removin g an d installin g
the rear wheel, always check
the brake ped al free play.
If proper a djustment cannot b e
o b taine d as descri bed , have a
Yamaha dealer make this a d-
justment.
1. Locknut
2. Brake lever free play adjusting bolt
2
1
(b)
(a)
1. Brake pedal free play adjusting nut
2. Brake pedal free play
Brake pe dal free play:
10.0–20.0 mm (0.39–0.79 in)
UB5185E0.book Page 19 Monday, June 17, 2019 9:04 AM