2003 YAMAHA TTR125 clock

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GEN
INFO
CONTROL FUNCTIONS
FUEL TANK CAP
Remove the fuel tank cap 1 by turning coun-
terclockwise.
WARNING
Do not overfill the fuel tank. Avoid spilling
fuel on the hot engine.
SIDESTAND
This sidestand 1 is used to support only the
machine when standing or transporting it.
WARNING
Never apply additional force to the side-
stand.
Hold up the sidestand before starting out.

SPEC
2 - 9
MAINTENANCE SPECIFICATIONS
Stem runout limit----0.01 mm
(0.0004 in)
Valve seat width IN0.9 ~ 1.1 mm
(0.0354 ~ 0.0433 in)1.6 mm
(0.0630 in)
EX 0.9 ~ 1.1 mm
(0.0354 ~ 0.0433 in)1.6 mm
(0.0630 in)
Valve spring:
Free length IN 32.55 mm (1.28 in) 31.2 mm
(1.23 in)
EX 32.55 mm (1.28 in) 31.2 mm
(1.23 in)
Set length (valve closed) IN 25.6 mm (1.01 in) ----
EX 25.6 mm (1.01 in) ----
Compressed pressure
(installed) IN 137.5 ~ 158.1 N
(14.0 ~ 16.1 kg, 30.86 ~ 35.49 lb)----
EX 137.5 ~ 158.1 N
(14.0 ~ 16.1 kg, 30.86 ~ 35.49 lb)----
Tilt limit * IN ---- 2.5˚/1.4 mm
(2.5˚/0.06 in)
EX ---- 2.5˚/1.4 mm
(2.5˚/0.06 in)
Direction of winding
(top view) IN Clockwise ----
EX Clockwise ---- Item Standard Limit

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INSP
ADJ
VALVE CLEARANCE INSPECTION AND ADJUSTMENT
4. Check:
Valve clearance
Out of specification → Adjust.
Valve clearance (cold):
Intake valve:
0.08 ~ 0.12 mm
(0.0031 ~ 0.0047 in)
Exhaust valve:
0.10 ~ 0.14 mm
(0.0039 ~ 0.0055 in)
Checking steps:
Turn the crankshaft counterclockwise with
a wrench.
Align the T.D.C. mark a on the rotor with
the align mark b on the crankcase cover
when piston is at T.D.C. on compression
stroke.
Measure the valve clearance using a
feeler gauge 1.
Out of specification → Adjust clearance.
5. Adjust:
Valve clearance
Adjustment steps:
Loosen the locknut 1.
Turn the adjuster 3 in or out with the
valve adjusting tool 2 until specified clear-
ance is obtained.
Turning in →
Valve clearance is decreased.
Turning out →
Valve clearance is increased.
Tappet adjusting tool:
YM-8035/90890-01311
Hold the adjuster to prevent it from moving
and tighten the locknut.
T R..
Locknut:
8 Nm (0.8 m • kg, 5.8 ft • lb)

3 - 18
INSP
ADJ
BRAKE PEDAL HEIGHT ADJUSTMENT
1. Check:
Brake pedal height a
Out of specification → Adjust.
2. Adjust:
Brake pedal height
FRONT BRAKE PAD INSPECTION AND
REPLACEMENT (TT-R125LW)
1. Remove:
Plug
2. Inspect:
Brake pad thickness a
Out of specification → Replace as a set.
Brake pedal height a:
1 mm (0.04 in)
Pedal height adjustment steps:
Loosen the locknut 1.
Turn the adjusting bolt 2 until the pedal
height a is within specified height.
Tighten the locknut.
Brake pad thickness a:
Standard
4.0 mm
(0.16 in)0.8 mm
(0.03 in)
3. Replace:
Brake pad
Brake pad replacement steps:
Remove the brake caliper support bolt 1.
Turn the brake caliper 2 counterclock-
wise a.
Replace the brake pads 3.
BRAKE PEDAL HEIGHT ADJUSTMENT/FRONT BRAKE
PAD INSPECTION AND REPLACEMENT (TT-R125LW)

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ENGCYLINDER HEAD
REMOVAL POINTS
Cylinder head
1. Align:
“I” mark
(with stationary pointer)
Checking steps:
Turn the crankshaft counterclockwise with
a wrench.
Align the “I” mark a on the rotor with the
stationary pointer b on the crankcase
cover. When the “I” mark is aligned with
the stationary pointer, the piston is at the
Top Dead Center (T.D.C.).
NOTE:
In order to be sure that the piston is at Top
Dead Center, the match mark c on the
camshaft sprocket must align with the sta-
tionary pointer d on the cylinder head as
shown in the illustration.
2. Loosen:
Camshaft sprocket bolt 1
NOTE:
Remove the bolt while holding the rotor nut
with a wrench.
3. Remove:
Bolt (timing chain tensioner cap) 1
Bolt (timing chain tensioner) 2
Timing chain tensioner 3

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ENGCYLINDER HEAD
3. Install:
Timing chain
Camshaft sprocket
4. Install:
Washer
Bolt (camshaft sprocket)
NOTE:
Temporarily tighten the bolt (camshaft sprocket)
at this point. Installation steps:
Turn the crankshaft counterclockwise with
a wrench.
Align the “I” mark a on the rotor with the
stationary pointer b on the crankcase
cover.
Align the match mark c on the camshaft
sprocket with the stationary pointer d on
the cylinder head.
Fit the timing chain 1 onto camshaft
sprocket 2 and install the camshaft
sprocket on the camshaft.
NOTE:
When installing the camshaft sprocket, keep
the timing chain as tense as possible on the
exhaust side.
CAUTION:
Do not turn the crankshaft during instal-
lation of the camshaft. Damage or
improper valve timing will result.
Remove the safety wire from the timing
chain.

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ENGCYLINDER HEAD
5. Install:
Timing chain tensioner
6. Turn:
Crankshaft
Counterclockwise several turns
7. Check:
Rotor “I” mark
Align with the crankcase stationary
pointer.
Camshaft match mark
Align with the cylinder head stationary
pointer.
Out of alignment → Adjust. Installation steps:
While pressing the tensioner rod lightly
with fingers, use a thin screwdriver and
wind the tensioner rod up fully clockwise.
With the rod fully wound, install the gasket
1 and the chain tensioner 2, and tighten
the bolts 3 to the specified torque.
T R..
Bolt (chain tensioner):
10 Nm (1.0 m • kg, 7.2 ft • lb)
Release the screwdriver, check the ten-
sioner rod to come out and tighten the
gasket 4 and the cap bolt 5 to the speci-
fied torque.
T R..
Cap bolt (timing chain tensioner):
8 Nm (0.8 m • kg, 5.8 ft • lb)
8. Tighten:
Bolt 1
NOTE:
Tighten the bolt while holding the rotor nut with
a wrench.
T R..20 Nm (2.0 m · kg, 14 ft · lb)

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ENGCLUTCH AND PRIMARY DRIVEN GEAR
Clutch
1. Install:
Conical spring washer 1
Thrust plate 2
Primary driven gear 3
Thrust plate 4
Clutch boss 5
2. Install:
Lock washer
Nut (clutch boss) 1
NOTE:
Use the clutch holding tool 2 to hold the clutch
boss.
ÅFor USA and CDN
ıExcept for USA and CDN
3. Bend:
Lock washer tab
Clutch holding tool:
YM-91042/90890-04086
New
T R..60 Nm (6.0 m · kg, 43 ft · lb)
Å
ı
4. Install:
Friction plate 1
Clutch plate 2
NOTE:
Install the clutch plates and friction plates
alternately on the clutch boss, starting with a
friction plate and ending with a friction plate.
Apply the engine oil on the friction plates and
clutch plates.
Be sure to install a clutch plate with projec-
tion a offset approximately 90˚ from previ-
ous plates projection. Continue this
procedure in a clockwise direction until all
clutch plates are installed.