Part Description
Hastings, 3-5/16" piston rings. STD
3-5/16" piston ring set with 3/32" (.09375") gray iron parkerized compression and 3/16" (.186") chromed 3-piece oil rings. Fits 37-48 74" (1200cc) 'U' model Flatheads and 48-52 61" (1000cc) E; EL Panhead models. Std bore: 3-5/16" (84.138mm). 1st ring: 2.38mm (3/32"). 2nd ring: 2.38mm (3/32"). oil ring: 4.75mm (3/16"). Tech tip: Piston grooves vs piston rings. It's not difficult to determine if a Hastings piston ring set will fit a certain piston. You should measure the height of the piston groove in the piston itself. The 2 top grooves will be for compression rings; the lower groove will be for the oil ring. In most cases Hastings oil rings are of the low tension 3-piece flex vent type. Ring heights are listed for reference. Tech tip: Piston oversizes. For each oversize cylinder diameter will increase with .010" (0.254mm). The standard bore of the cylinder is listed for reference. (Tech tip information provided by Hastings Manufacturing Company; Inc.)
