Differences between CB model engines

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My 993cc Hijet has engine problems and I am considering rebuilding it using the best parts of the two engines I have, however without a workshop manual I am at a loss as to the required tolerances. Does anyone know if the workshop manual for the CB-23 engine(includes CB-60 & CB-80 I think) can be used to rebuild the CB-42 engine with regards to torque settings and tolerances Unknw

Torque settings etc for CB-42

N-m
Cylinder head x Spark plug 14.7 - 21.6
Cylinder head x Cylinder block 53.9 - 63.7
Cylinder head cover x Cylinder head
M8 7.8 -11.8
M6 2.9 - 4.9
Timing belt cover 2.0 - 3.9
Crankshaft bearing cap x Cylinder block 53.0 - 64.7
Cylinder block x Oil pan 3.9 - 6.9
Cylinder block x Balance shaft thrust plate 9.8 -14.7
Connecting rod x Connecting rod cap 23.5 - 30.4
Flywheel x Crank shaft 39.2 - 49.0
Crankshaft pulley x Crankshaft 88.3 - 98.0
Camshaft timing belt pulley x Camshaft 29.4-44.1
Timing belt tensioner x Balance gear cover 33.3-44.1
Cylinder block x Oil pump 14.7 - 21.6
Water pump x Water pump pulley 5.9 - 8.8
Cylinder head x Intake manifold 14.7 - 21.6
Cylinder head x Exhaust manifold 14.7-21.6
Balance shaft gear cover x Cylinder block 9.8 - 15.7
Balance shaft weight x Balance shaft 29.4-44.1
Oxygen sensor x Exhaust manifold 29.4 - 39.2
Coolant temperature sensor x Cylinder head 24.5 - 34.3
Intake air temperature sensor x Intake manifold 29.4 - 39.2
Coolant temperature sender x Intake manifold 9.8- 17.6
Delivery pipe x Intake manifold 14.7-21.6

Timing belt pulley Wear limit (Minimum limit-
Camshaft 119.9 mm (4.270 inch)
Crankshaft 59.2 mm (2.331 inch)

Camshaft
Oil clearance
Front STD 0.04 - 0.14 mm (0.0016 - 0.0055 inch)
Center STD 0.09 - 0.19 mm (0.0035 - 0.0075 inch)
Rear STD 0.06 - 0.16 mm (0.0024 - 0.0063 inch)
Reference Journal diameter
Front 31.960 - 31.980 mm (1.2583 - 1.2591 inch)
Center 47.385 - 47.410 mm (1.8656 - 1.8665 inch)
Rear 48.415 - 48.440 mm (1.9061 - 1.9071 inch)
Cam lobe height
Intake Minimum limit 39.8 mm (1.5669 inch)
Exhaust Minimum limit 39.8 mm (1.5669 inch)

Runout [Bend] 0.03 mm (0.0012 inch)

Uneven wear of camshaft journal Maximum limit 0.02 mm (0.0008 inch)
Cylinder head Flatness
Cylinder block side 0.1 mm
Intake manifold side 0.1mm
Exhaust manifold side 0.1mm

Valve seat angel Intake 45° Exhaust 45deg

Valve guide bushes
Oil clearance
Intake 0.040 - 0.075 mm (0.0016 - 0.0030 inch)
Exhaust 0.045 - 0.080 mm (0.0018 - 0.0031 inch)

Valves Contact width with valve seat 1.0 - 1.8 mm (0.0394 - 0.0709 inch)

Valve face angle 45.5°

Valve stock thickness
Intake 0.9 -1.5 mm (0.035 - 0.059 inch)
Exhaust 1.2 -1.8 mm (0.047 - 0.071 inch)

Valve stem outer diameter
Intake 6.945 - 6.960 mm (0.2734 - 0.2740 inch)
Exhaust 6.940 - 6.955 mm (0.2732 - 0.2738 inch)

Overall length
Intake 101.65 mm (4.002 inch)
Exhaust 101.65 mm (4.002 inch)

Vaive spring Free length 43.3 mm (1.7047 inch)

Installed tension at 34.9 mm
STD 29.9 kg
Minimum limit 25.7 kg

Valve rocker arm and valve rocker shaft
Oil clearance between rocker arm and rocker shaft 0.016 - 0.09 mm (0.0006 - 0.0035 inch)
Valve rocker arm inner diameter 16.000 -16.018 mm (0.6299 - 0.6306 inch)
Vaive rocker shaft outer diameter 15.958 -15.984 mm (0.6283 - 0.6293 inch)
Valve rocker arm spring Minimum free length 33 mm (1.299 inch)
Cylinder block Flatness cylinder head gasket attaching surface STD 0.1 mm (0.0039 inch)
Maximum limit 0.1mm

Cylinder
Oil clearance between piston-to-cylinder
STD 0.03 - 0.12 mm (0.0012 - 0.0047 inch)
Maximum limit 0.12 mm (0.0047 inch)

Cylinder bore diameter (When over size piston is used)
STD 76.00 - 76.03 mm (2.9921 - 2.9933 inch)
O/S 0.25 76.25 - 76.28 mm (3.0020 - 3.0031 inch)
O/S 0.50 76.50 - 76.53 mm (3.0118 - 3.0130 inch)

Piston, piston pin and piston rings
Piston ring groove-to-piston ring side clearance
No. 1 0.03 - 0.07 mm (0.0012 - 0.0028 inch)
No. 2 0.02 - 0.06 mm (0.0008 - 0.0024 inch)

Piston ring thickness
No. 1 1.47 -1.49 mm (0.0579 - 0.0587 inch)
No. 2 1.47 -1.49 mm (0.0579 - 0.0587 inch)

Piston ring end gap
No. 1 0.20 - 0.70 mm (0.008 - 0.028 inch)
No. 2 0.20 - 0.70 mm (0.008 - 0.028 inch)
Oil 0.20 -1.10 mm (0.008 - 0.043 inch)

Piston, piston pin and piston rings
Piston-to-piston pin oil clearance
Maximum limit 0.03 mm (0.0012 inch)

Piston pin-to-connecting rod interference fit
0.012 - 0.019 mm (0.0005 - 0.0019 inch)

Connecting rod
Big end thrust clearance
0.150 - 0.30 mm (0.0059 - 0.0118 inch)
Maximum bend 0.05 mm (0.0020 inch)
Maximum twist 0.05 mm (0.0020 inch)

Crankshaft
Crankshaft bend 0.06 mm (0.0024 inch)
Uneven wear of main journal and crankpin journal 0.01 mm (0.0004 inch)
Main and crankpin journal oil clearance 0.020 - 0.070 mm (0.0008 - 0.0027 inch)
Crankshaft thrust clearance 0.02 - 0.30 mm (0.0008 - 0.0118 inch)

Balance shaft
Balance shaft thrust clearance 0.03 - 0.20 mm (0.0012 - 0.0078 inch)
Balance shaft bearing oil clearance 0.025 - 0.1 mm (0.0010 - 0.0039 inch)

Timing belt pulley
Camshaft timing belt pulley outer diameter Minimum limit 119.9 mm (4.270 inch)
Crankshaft timing belt pulley outer diameter Minimum limit 59.2 mm (2.331 inch)

Fly wheel Runout Maximum limit 0.10 mm (0.0039 inch)

Crankshaft main journal bearing Bearing
center thickness
Replacement STD bearing 1.986 - 2.006 mm (0.0782 - 0.0790 inch)
Undersize 0.25 bearing 2.111 -2.131 mm (0.0831 - 0.0839 inch)
Undersize 0.50 bearing 2.236 - 2.256 mm (0.0880 - 0.0888 inch)

Crankpin journal bearing (Connecting rod bearing)
Bearing center thickness Replacement STD bearing 1.486 -1.506 mm (0.0585 - 0.0593 inch)
Undersize 0.25 bearing 1.611 -1.631 mm (0.0634 - 0.0642 inch)
Undersize 0.50 bearing 1.736 -1.756 mm (0.0683 - 0.0691 inch)

Crankshaft thrust bearing
Bearing center thickness
STD 1.940 - 1.990 mm (0.0764 - 0.0783 inch)
Oversize 0.25 bearing 2.065 - 2.115 mm (0.0813 - 0.0833 inch)
Oversize 0.50 bearing 2.190 - 2.240 mm (0.0862 - 0.0882 inch)

If I have missed anything, let me know!

Engine Specs

Thankyou for the information you have provided, hopefully I can now rebuild my 993cc unit. Out if interest where did you get these specifications that have evaded me for so long Unknw