{"product_id":"mcs946454","title":"Hastings 2-3\/4\" Bore Piston Ring Set. +.020\" – 1950–1973 45\" (750cc) Flathead; All…","description":"\u003ch2\u003eHastings 2-3\/4\" Bore Piston Ring Set. +.020\" – 1950–1973 45\" (750cc) Flathead; All…\u003c\/h2\u003e\n\u003cp\u003eUsed with late style 1950-1973 type pistons with 1\/16\" gray iron parkerized compression rings and the 3-piece flex-vent style chrome oil rings. Also fits 52-56 K; KH; KHK 55\" (900cc) Flathead models. Std Bore: 2.745\" (69.723mm). 1st ring: 1.6mm. 2nd ring: 1.6mm. oil ring: 4.75mm. Note: OEM 1929-1949 pistons are equipped with 3\/32\" (2.3mm) 1st. \u0026amp; 2nd rings and 1\/8\" (3.2mm) oil ring; for these Hastings rings see 1950-1973 Flathead model years. These rings will not fit the 1929-1949 early type pistons. 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.)\u003c\/p\u003e\n\u003ch2\u003eFitment\u003c\/h2\u003e\n\u003cp\u003e50-73 45\" (750cc) Flathead; all 52-56 K 45\" (750cc) and KH; KHK 55\" (900cc) Flathead models (NU)\u003c\/p\u003e\n\u003ch2\u003eProduct Details\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Hastings\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e MOTOR PARTS \u0026gt; PISTON RINGS\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUnit:\u003c\/strong\u003e 2CY\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct code:\u003c\/strong\u003e 946454\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Hastings","offers":[{"title":"Default Title","offer_id":57378718318979,"sku":"MCS946454","price":43.27,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1329\/4265\/files\/946454k_4f895102-ac20-4ecf-89bb-87371ced4b03.jpg?v=1775575451","url":"https:\/\/hogparts.com\/products\/mcs946454","provider":"Hogparts UK Ltd","version":"1.0","type":"link"}