Benelli TNT125 - Preparation Information; Technical Parameters; Torque Value

Preparation Information
●Function of Cylinder Head:
Cylinder head is used to seal the cylinder and it
forms a combustion chamber
with the piston to
withstand the high temperature and high pressure gas.
And it can also complete the intake and exhaust
through the valve mechanism.
●Operation Precautions:
In order to ensure the sealing of cylinder head and
upper box, the
cylinder head withstands great bolt
locking force. Pre-tightening force: 12
N·m, locking
force: 19-23 N·m.
Before the inspection and measurement, all parts
shall be cleaned and blown with high-pressure air.
Technical Parameters
Table of standard value and allowable limit of benchmark items Unit: mm
Item Standard Use limit
Planeness of cylinder head 0.05 0.05
Valve
valve guide
Valve clearance:
Inlet
0.08-0.1
＿
Outlet 0.08-0.1
＿
Outer diameter of valve stem:
Inlet
4.48-4.49
4.45
Outlet
4.465-4.475
4.44
Inner diameter of valve guide:
Inlet 4.5-4.512 4.55
Outlet 4.5-4.512 4.54
Clearance between valve stem
and valve guide
Inlet 0.01-0.032 0.1
Outlet 0.025-0.047 0.1
Width of valve seat:
Inlet
1-1.2
1.5
Outlet 1-1.2 1.5
Valve spring Free length
Inlet 38.5 37.7
Outlet
38.5
37.7
Camshaft Height of camshaft
Inlet 29.5626 29.5426
Outlet 29.5576 29.5376
Torque Value
Cylinder head screw
19-23N•m
Stud bolt of air inlet duct 10-12N•m
Stud bolt at exhaust side 10-12N•m
Bolt at sprocket cavity
10-12N•m
Spark plug 12-15N•m
Sprocket bolt
20-24N•m
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