1996-2005 Suzuki DF40, DF50 Four Stroke Outboard Service Manual, Page 190Get this manual
6-47 POWER UNIT PISTON RING Piston ring end gap Measure piston ring end gap with piston ring in the lowest position of cylinder bore09900-20803: Thickness gauge Piston ring end gap Standard: st 0.10 0.25 mm (0.004 0.010 in nd 0.25 0.40 mm (0.010 0.016 in Service limitst 0.70 mm (0.028 in nd 1.00 mm (0.039 in If measurement exceeds service limit, replace piston ringPiston ring