1977-2000 Suzuki DT5/6/8 Outboards Service Manual, Page 42Get this manual
ENGINE Check the gasketed surface of the cylinder and also the exhaust port side surface for flantness in the already outlined for the cylinder headUse straightedge and thickness gaugeThe limit of flatness is, as in the case of the cylinder head, 0.03 mm (0.0012 in) part of the surface as checked in the following directions as shown
Check the gasketed surface of the exhaustThe wear of cylinder wall is determined from diameter reading taken, as shown, total of 6-place with cylinder gauge