Honda CB250N Shop Manual page 157

CB250
Addendun
r—
:
Cylinder
Head
Item Standard
Unit:
mrn
(in
Service Limit
Cylinder
compression
{kPa (kgf/cm
z
,
psi)/500
- 600
mim
1
(rpm)l
Cylinder compression difference
{kPa (kgf/cm z
,
psi)/500
- 600 min-
1 (rpm)}
Valve clearance
IN
EX
Cylinder
head warpage
Cam
lobe
height©
IN
EX
Camshaft runout
Camshaft
oil
clearance
A
B
©
Camshaft
journal O.D.
A
B
Camshaft bushing
I.
D.
Camshaft
holder
l.D.
A
B
Valve
stem
O.D. IN
EX
Valve guide
l.D.
IN
EX
Stem-to-guide clearance IN
EX
Valve guide projection
above
cylinder
head
IN
EX
Before
guide
installation:
1,
Chill
the valve guides
in
the freezer section of
the
refrigerator for
about an hour
2.
Heat the
cylinder
head
to
100-
150°C (212 -
300-F)
Valve seat
width
VstVe soring free length' IN
EX
inner IN
inner
EX
outer
IN
-
outer
EX
Rocker
arm
l.D.
IN
EX
Sub-rocker
arm
l.D.
IN
EX
Rocker
arm
shaft O.D.
IN
EX
Sub-rocker
arm
shaft
O.D. IN
EX
Rocker arm-to-rocker
arm
shaft clearance
Sub-rocker arm-to-rocker
arm
shaft
clearance
Valve
lifter
O.D.
Valve
lifter
bore
l.D.
Hydraulic
tash adjuster assist
spring
free length'
'
Hydraulic
lash adjuster
compression
stroke with
kerosene
1,373-
1.471
(14-
15.
199-213)
98
(1,
14}
"'
.
0.D6-0.10
(0.002
- 0.004)
0.06-
0.10
(0.002-
0.004)
27.383-27.543
(1.0781
-
1.0844)
27.209
-27.369
(1.0712 - 1.0775)
19.967-
19.980 [0.7861
-0.7866!
20.063 - 20.083 (0.7899
-
0.7907)
5.450 - 5.465 (0.2146
-
0.2152)
5.430
-
5.445 (0.2138
-
0.2144)
5.475-
5.485
(0.2156-0.2159)
5.475-5.485 (0.2156-
0.2159)
0.010
- 0.035 (O.0004 - 0.001
4)
0.030-
0.055 (0.0012
-
0.0022}
1.0-
1.1
(0.039-0.043)
29.9
(1.18)
29.9(1.18)
38.2
(1.50}
38.2(1.50)
-
-
1Q.O00
-
10.015 (0.3937
-
0.3943)
10.000- 10.015 (0.3937-0.3943)
9.978
-
9.987
(0.3928-0.3932)
9.978 - 9.987 (0.3928-
0.3932)
0.013-
0.037 (0.0005 - 0.0015)
785
(8,
114)
0.10
(0.004)
27.2
(1.07)
27.0
(1.06)
0.05
(0.002)
19.92 (0.784)
20.20
(0.795)
5.42 (0.213)
5.40 (0.213)
5.50
(0.217)
5.50 (0.217)
0.08 (0.003)
0.10
(0.004)
1.8 (0.07)
29.0
(1-.14)
29.0
(1.14)
37.0
(1.46).
•
37.0
(1.46)
10.10 (0.398)
10.10 (0.398)
9.91 (0.390)
9.91 (0.390)
0.Q5
(0.002)
<
;
19-5