6
. CYLINDER HEAD/VALVES
6-2
DOWNTOWN 125i
SERVICE INFORMATION
GENERAL INSTRUCTIONS
•
The cylinder head can be serviced with the engine installed in the frame. Coolant in the radiator
and water jacket must be drained first.
•
When assembling, apply molybdenum disulfide grease or engine oil to the valve guide movable
parts and valve arm sliding surfaces for initial lubrication.
•
The valve rocker arms are lubricated by engine oil through the cylinder head engine oil passages.
Clean and unclog the oil passages before assembling the cylinder head.
•
After disassembly, clean the removed parts and dry them with compressed air before inspection.
•
After removal, mark and arrange the removed parts in order. When assembling, install them in
the reverse order of removal.
SPECIFICATIONS
Unit: mm
Item
Standard
IN
0.1
EX
0.1
Cylinder head compression pressure
15kg/cm²
Cylinder head warpage
⎯
IN
25.965
Camshaft cam height
EX
25.810
IN
10.0~10.015
Valve rocker arm I.D.
EX
10.0~10.015
Valve rocker arm shaft
IN
9.972~9.987
O.D.
EX
9.972~9.987
IN
4.975~4.970
Valve stem O.D.
EX
4.975~4.970
IN
5.0~5.012
Valve guide I.D.
EX
5.0~5.012
Valve stem-to-guide
IN
0.010~0.037
clearance
EX
0.030~0.057
TORQUE VALUES
Cylinder head cover bolt
0.8~0.9 kgf-m
Tensioner mounting bolt
0.9 kgf-m
Tensioner sealing bolt
0.9 kgf-m
Cylinder head cap nut
2 kgf-m
Apply engine oil to threads
Cylinder head bolt
0.7~1.1 kgf-m
Valve clearance (cold)
Cortesia de/ Courtesy of: www.batmotos.com
Cortesia de/ Courtesy of: www.batmotos.com