Piston assembly (complete with piston, rings, gudgeon, circlips) to suit Norton ES2 , Model 18, OHV 1948 to c1962. 79mm + 0.40 oversize. Italian made by Gandini (GPM) #7915-100. Can be used for pre 1948 motors with large flywheels if the skirt length is reduce by machining. Compression height 35mm. This raises the compression from 6.6:1 to 7.1:1 for engines 1948 to 1956.Original Norton part number:3790 - Piston assembly with gudgeon pinA3/160; A3/161; A3/162; A3/163; A3/164C3/702; L4/702; 19776 - Piston complete with rings, gudgeon pin and circlips
