Honda BF20A-BF25A, BF25D-BF30D Outboard Motors Shop Manual., Page 123Get this manual
HONDA BFSOAeSSA
4INSPECTION
For pistons, crankshaft, and cylinder inspection, measure the followingIf needed, replace them
PISTON SKIRT O.DMeasure and record the piston O.Da point 10 mm (0.4 in) from the bottom, and 90 to the piston pin boreSTANDARD 57.970- 57.990 mm (2.2823- 2.2831 in) SERVICE LIMIT 57.92 mm (2.280 in) 10 mm (0.4 in)
PISTON PIN HOLE I.D
STANDARD 14.00214.008 mrn (0.5513-0.551 in)