Brixton BX125 - Service Data

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Service data 10.1
Fault Diagnosis 10.2
Cylinder head/Valve 10.3
10.1 Service Data
Function of cylinder head:
It is used to seal cylinder and form the combustion chamber along with the piston in order to
withstand high-temperature and high-pressure combustible gas. Through the valve system, the
cylinder head intakes and discharges gas.
Precautions:
To ensure seal between the cylinder head and cylinder body, the head withstand large locking tension force
from bolt. Locking-tension value: 30Nm.
All parts must be cleaned before being checked, and purged with high-pressure air.
Standard Value and Allowable Limit of Reference Items Unit: mm
Item
Standard
Allowable limit
Valve
Valve guide
Valve stroke
Intake
0.04-0.06
-
Discharge
0.09-0.11
-
OD, valve rod
Intake
4.975-4.990
4.955
Discharge
4.955-4.970
4.958
OD, valve rod
Intake
5-5.012
5.03
Discharge
5-5.012
5.03
Clearance of valve rod and
valve guide
Intake
0.01-0.037
0.065
Discharge
0.03-0.057
0.082
Width, valve base
Intake
1.1-1.3
1.6
Discharge
1.0-1.2
1.6
Valve spring
Free length
Intake
41.8
39.5
Discharge
41.8
39.5
Camshaft
Stroke of camshaft and cylinder head
0.02-0.054
0.08
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