Interpretation piston to cylinder bore clearance

Jens

Member
According to the WSM: the A type piston dimension (diameter I guess) must be 0.018-0.033 mm smaller the the cylinder (bore dimension/diameter of 88.90mm).
Is this the total clearance or the clearance left and right with the piston in the middle of the cylinder ? so total clearance should be twice the value of 0.018-0.033mm.

Example: a 88.77mm piston diameter gives a clearance of cylinder bore diameter of 88.90 minus 88.77=0.13mm.
Do I have to compare 0.13mm with the WSM tolerance of 0.018-0.033mm or to compare with half the value of 0.13mm = 0.065mm with the tolerance of 0.018-0.033mm ?
 
If the piston diameter is 0.018-0.033 smaller than the bore, the radial clearance around the piston will be in the range 0.009 - 0.0165mm
 
clearance is actual bore diameter, less Actual piston diameter as measured across bottom of piston skirt.
 
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