Yamaha BR250F Service Manual page 137

a
MAINTENANCE SPECIFICATIONS
Engine
Model
Cylinder head:
Volume (With spark plug)
Warp Limit
Cylinder:
Material
Bore Size
Taper Limit
Out-of-Round Limit
Piston:
Piston Size (D)/Measuring Point (a)
o
/~~-
D
' 7
Clearance between Piston & Cylinder
Oversize 1st
2nd
3rd
4th
Piston Pin Hole Off- Set
BR250T
J
33.1 -- 33.7 cm' (2.02 -- 2.06 cu.in)
Aluminum alloy with special cast iron sleeve
70.000 -- 70.020 mm (2.756 ""' 2.757 in)
<
0.05 mm (0.0020 in)
>
<
0.01 mm (0.0004 in)
>
69.950 -- 69.980 mm (2.754 -- 2.755 in)/
10 mm (0.394 in)
0.045'" 0.050 mm (0.0018'" 0.0020 in)
72.25 mm (2.845 in)
72.50 mm (2.854 in)
1.0 mm (0.04 in) Exhaust side
Piston Pin:
Outside Diameter x Length
Piston Ring:
Sectional Sketch
End Gap (Installed)
Side Clearance
Coating
Top Ring
2nd Ring
Top Ring
2nd Ring
Top Ring
2nd Ring
Top Ring
2nd Ring
...
24-
18 x 55 mm (0.71 x 2.71 in)
" - .." _._ _- .. - - - - . - - -..- - - - - i
Keystone
B 1.2 mm (0.047 in)
T:::: 2.8 mm (0.110 in)
Plain
B:::: 1.2 mm (0.047 in)
T 2.8 mm (0.110 in)
0.20 -- 0.40 mm (0.0079'" 0.00157 in)
0.20 -- 0.40 mm (0.0079 -- 0.00157 in)
0.03 -- 0.07 mm (0.0008 -- 0.0024 in)
0.02"" 0.06 mm (0.0008"" 0.0024 in)
Parkerizing
Parkerizing