{"product_id":"49-0878-18mm-doering-spark-plug-set","title":"18mm Doering Spark Plug Set 1930 \/ 1936 VL 1930 \/ 1936 RL 1926 \/ 1929 J 1937 \/ 1947 W 1937 \/ 1948 U 1936 \/ 1947 G 1924 \/ 1930 JD","description":"\u003cp\u003e\u003c\/p\u003e\u003cp\u003eLarge hex original design for air cooled engines  #3 heat range terminal nuts and seal washers included. Includes top ventilated brass collars for cooling  as original  Doering design! Terminal nut is removable. Plug set has a round feeler gauge. Spark plugs have a 18mm thread and the large hex measures 1-3\/8   which is perfect for early restoration and riding. Set is for use with 1924 Harley models that require 7\/8  thread spark plug. *NOTE: Sold as a pair.  *NOTE: Fits early Knuckleheads  that can accept the 1-3\/8  large hex. *NOTE: Air cooled spark plug set features a nickel plated full size hex. Full size hex is for single and twin flat heads  For IOE types  with space for the large hex. Doering Spark Plug Company was founded in Brooklyn  NY in 1918  making plugs for tractors. In the later years  they made plugs for automotive applications  for motors that burned an excessive amount of oil. They are manufactured to the original standards of that era  but not in Brooklyn any longer.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFITMENT\u003c\/b\u003e\u003c\/p\u003e \u003cli\u003e1930 \/ 1936 VL  \u003c\/li\u003e\u003cli\u003e1930 \/ 1936 RL  \u003c\/li\u003e\u003cli\u003e1926 \/ 1929 J  \u003c\/li\u003e\u003cli\u003e1937 \/ 1947 W  \u003c\/li\u003e\u003cli\u003e1937 \/ 1948 U  \u003c\/li\u003e\u003cli\u003e1936 \/ 1947 G  \u003c\/li\u003e\u003cli\u003e1924 \/ 1930 JD  \u003c\/li\u003e\u003cp\u003e\u003c\/p\u003e\u003cp\u003e\u003cb\u003eTECH NOTES\u003c\/b\u003e\u003c\/p\u003e\u003cli\u003eSet gap at .025inch.\u003c\/li\u003e\u003cli\u003e*NOTE: Some head fins must be clearanced to accept the early large hex 1-3\/8inch plugs.\u003c\/li\u003e\u003cp\u003e\u003c\/p\u003e\u003cp\u003e\u003cb\u003eACCESSORY ITEMS\u003c\/b\u003e\u003c\/p\u003e\u003cli\u003e49-0880\u003c\/li\u003e\u003cli\u003e16-1387\u003c\/li\u003e\u003cli\u003e49-0980\u003c\/li\u003e\u003cli\u003e32-1231\u003c\/li\u003e","brand":"V-TWIN MANUFACTURING","offers":[{"title":"Default Title","offer_id":31491216474223,"sku":"49-0878","price":82.67,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0081\/7401\/0479\/products\/49-0878_714eec47-3c2d-4b48-88c4-2824231e581c.jpg?v=1588456430","url":"https:\/\/www.widowmakersboneyard.com\/products\/49-0878-18mm-doering-spark-plug-set","provider":"Widowmaker's Boneyard","version":"1.0","type":"link"}