2004 YAMAHA TTR90 valve clearance

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ENGCYLINDER HEAD
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.
4. Install:
Washer
Bolt 1
NOTE:
Install the bolt 1 while holding the rotor nut
with a wrench.
T R..20 Nm (2.0 m · kg, 14 ft · lb)
5. Install:
Timing chain tensioner
6. Check:
Rotor “I” mark
Align with the crankcase stationary
pointer.
Valve clearance
Out of specification → Adjust.
Refer to the “VALVE CLEARANCE
ADJUSTMENT” section in CHAPTER 3. Installation steps:
Remove the tensioner cap bolt 1 and
spring 2.
Release the timing chain tensioner one-
way cam 3 and push the tensioner rod 4
all the way in.
Install the tensioner with a new gasket 5
onto the cylinder.
T R..
Timing chain tensioner bolt:
10 Nm (1.0 m • kg, 7.2 ft • lb)
Install the spring 2 and cap bolt 1.
Tighten the bolt (with gasket) to the speci-
fied torque.
T R..
Cap bolt:
8 Nm (0.8 m • kg, 5.8 ft • lb)

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ENGCAMSHAFT AND ROCKER ARMS
CAMSHAFT AND ROCKER ARMS
Extent of removal:1 Rocker arm2 Camshaft removal
Extent of removal Order Part name Q’ty Remarks
CAMSHAFT AND ROCKER
ARMS
Preparation for removal Cylinder head Refer to “CYLINDER HEAD” section.
1 Rocker arm shaft (intake) 1
Use special tool.
Refer to “REMOVAL POINTS”.
2 Rocker arm shaft (exhaust) 1
3 Rocker arm 2
4 Camshaft bearing retainer 1
5 Camshaft 1
6 Valve clearance adjust screw
locknut2
7 Valve clearance adjust screw 2
1
2

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ENGVALVES AND VALVE SPRINGS
REMOVAL POINTS
Valve removal
1. Remove:
Valve cotters 1
NOTE:
Attach a valve spring compressor 2 between
the valve spring retainer and the cylinder head
to remove the valve cotters.
Valve spring compressor:
YM-4019/90890-04019
INSPECTION
Valve
1. Measure:
Stem-to-guide clearance
Out of specification → Replace the
valve guide. Stem-to-guide clearance =
valve guide inside diameter a –
valve stem diameter b
Clearance (stem to guide):
Intake:
0.010 ~ 0.037 mm
(0.0004 ~ 0.0015 in)
: 0.08 mm (0.003 in)
Exhaust:
0.025 ~ 0.052 mm
(0.0010 ~ 0.0020 in)
: 0.10 mm (0.004 in)
2. Measure:
Runout (valve stem)
Out of specification → Replace.
Runout limit:
0.02 mm (0.0008 in)