Honda MBX50, Руководство по ремонту

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�HONDA
� MBX50,MBX80
CYLINDER HEAD/CYLINDER/PISTON
SERVICE INFORMATION
GENERAL INSTRUCTIONS
e All cylinder head maintenance and inspection can be accomplished with the engine installed.
8
Before disassembling the engine, clean the engine thoroughly to prevent dirt and dust to fall into the cylinder and crank-
case.
@
Remove all traces of gasket material from the mating surfaces of the cylinder head, cylinder and crankcase.
e Use caution when servicing the cylinder and piston to prevent damage to them.
111 Before assembling, apply clean engine oil to all sliding surfaces of parts.
TORQUE VALUE
Cylinder head nut
Intake pipe bolt
SPECIFICATIONS
ITEM
Cylinder head warpage
Cylinder bore MBX50
MBX80
Piston 0.0. (10 mm (3/8 in)
from piston skart)
Cylinder-to-piston
clearance
Piston pin bore
Piston pin 0.0.
Piston-to-piston pin clearance
Piston ring end gap (top/second)
Connecting rod small end 1.0.
MBX50
MBX80
Compression too low, hard starting or poor
performance at low speed
1. Blown cylinder head gasket
2. Loose spark plug
3. Worn, stuck or broken piston rings
4. Worn or dmaged cylinder and piston
5. Faulty reed valve
Compression too high, overheating or knocking
1. Excessive carbon build up in cylinder head or on
piston top
18-22 N.m (1.8-2.2 kg-m, 13-16 ft-lb)
8-12 N.m (0.8-1.2 kg-m, 6-9 ft-lb)
STANDARD mm (in)
38.998-39.013 mm
(1.5354-1.5359 in)
49.407-49.523 mm
(1.9452-1.9497 in)
38.955-38.970 mm
(1.5337-1.5343 in)
49.455-49.4 70 mm
(1.9470-1.9476 in)
0.035-0.050 mm
(0.0014-0.0020 in)
12.002-12.008 (0.4 725-0.4 728)
11.994-12.000 (0.4 722-0.4 724)
0.002-0.014 (0.0001-0.0006)
0.10-0.25
(0.004-0.010)
17.005-17.017 (0.6695-0.6700)
Abnormal noise-piston
1. Worn cylinder and piston
2. Worn piston pin or piston pin hole
3. Worn connecting rod small end bearing
Abnormal noise-piston rings
1. Worn, stuck or broken piston
rings
2. Worn or damaged cylinder
SERVICE LIMIT mm (in)
0.10
(0.004)
39.062 mm ( 1.5379 in)
49.572 mm (1.9516 in)
38.920 mm (1.5323 in)
49.420 mm (1.9457 in)
0.090 mm (0.0035 in)
12.030 (0.4 736)
11.980 (0.4717)
0.040
(0.0016)
0.35 (0.014)
17.030 (0.6705)
6-2