Generic Race 50, Service Manual

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162
XIII. Air cylinder/piston
Preparation data------------------------
13.1
Piston------------------------------
13.4
Fault diagnosis ------------------------
13.2
Installation of the piston---------
13.5
Cylinder body -------------------------
13.3
13.1 Preparation data
Matters needing attention in operation
All parts should be cleaned before inspection and test and should be blow dry with high pressure air.
Function of the cylinder body
：
The cylinder body provides space for the compression, burning and expansion of
air and plays a steering function to piston motion.
It also transmits part of the heat in the air cylinder to the surrounding cooling media.
Function of piston
：
Bearing the pressure caused by burning of combustible mixture gas and pass the pressure to the connecting rod,
driving the rotation of the crankshaft.
Shaping a combustion chamber with the cylinder cover and others.
Timingly press the fresh mixed gas from the crankcase into the cylinder and timely exhaust waste gas out of the
cylinder after combustion.
Preparation standard Unit
：mm
Item Standard value
Allowable
limi
internal diameter
39.995-40.015 40.05
bend
- 0.05
cylindricity
0.006 0.05
Air
cylinder
flatness
0.03 0.05