{"product_id":"biglknm-top-end-gasket-kit-for-harley-evo-big-twin-1340cc-complete-upper-engine-gaskets-seals","title":"BIGLKNM Top End Gasket Kit for Harley EVO Big Twin 1340cc — Complete Upper-Engine Gaskets \u0026 Seals","description":"\u003cp\u003e\u003cstrong\u003eBIGLKNM Top End Gasket Kit for Harley EVO Big Twin 80ci (1340CC) is a complete upper-engine gasket set designed to replace head, rocker, intake, and related seals for compatible Dyna, Softail, and Touring EVO models.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eIf you're rebuilding or refreshing the top end of a 1340cc Evolution (EVO) Harley-Davidson, this kit supplies the common head gaskets, rocker cover gaskets, cylinder base gaskets, intake seals, O-rings, and backing plates needed to reseal the engine properly. Components are matched to OEM-style fitment for mid‑1980s through late‑1990s EVO Big Twin applications and come in materials chosen for heat and oil resistance.\u003c\/p\u003e\n\n\u003ch3\u003eWhich Harley models does this gasket kit fit?\u003c\/h3\u003e\n\u003cp\u003eThis BIGLKNM kit is tailored for many EVO Big Twin years and families, covering specific Dyna, Softail, and Touring models. Double-check years and model codes against your bike before ordering to ensure exact compatibility.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eDyna: 1994–1998 Low Rider, Low Rider Custom, FXDL, FXDB, and related EFI\/convertible variants.\u003c\/li\u003e\n  \u003cli\u003eSuper Glide \/ FXD family: FXDI, FXDCI EFI, FXDWG and similar late‑90s models.\u003c\/li\u003e\n  \u003cli\u003eTouring: FLT\/Ultra Glide and Classic FLTC\/FLTCUI EFI variants.\u003c\/li\u003e\n  \u003cli\u003eSoftail: 1984–1998 Softail models including FXST, FXSTC and early EVO Softail V2.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat materials are used, and why do they matter?\u003c\/h3\u003e\n\u003cp\u003eBIGLKNM uses silicone head gaskets together with NBR (nitrile rubber) O-rings and seals to balance heat resistance and oil compatibility. These materials are widely used in aftermarket engine kits because they withstand EVO operating temperatures while maintaining sealing integrity when installed correctly.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eSilicone head gaskets for consistent compression sealing.\u003c\/li\u003e\n  \u003cli\u003eNBR O-rings and seals for oil resistance and elasticity.\u003c\/li\u003e\n  \u003cli\u003eMetal backing plates and washers to secure components and maintain clamping force.\u003c\/li\u003e\n  \u003cli\u003eRocker cover gaskets (upper and lower) designed to resist valve-train oiling.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat exactly comes in the package?\u003c\/h3\u003e\n\u003cp\u003eThe kit includes the full set of upper-end gaskets and associated hardware typically needed when removing heads and rocker covers. Packaging is arranged so you can verify each item against the pictured contents to confirm a complete top-end reseal kit.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eHead gaskets and cylinder base gaskets for both cylinders.\u003c\/li\u003e\n  \u003cli\u003eUpper and lower rocker cover gaskets plus rubber seals and washers.\u003c\/li\u003e\n  \u003cli\u003eIntake manifold gaskets, backing plates, multiple O-rings and seals.\u003c\/li\u003e\n  \u003cli\u003eAssorted washers and installation seals so you can reuse existing hardware or replace as needed.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow should I use this kit during a top-end service?\u003c\/h3\u003e\n\u003cp\u003eUse the kit when removing heads, replacing valve guides, or rebuilding the top end. Clean mating surfaces thoroughly, replace all gaskets and O-rings with the kit parts, and torque fasteners to factory specifications to prevent leaks and premature failure.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eClean and inspect cylinder head and block mating surfaces before installation.\u003c\/li\u003e\n  \u003cli\u003eReplace all gaskets and O-rings included; do not reuse old sealing parts.\u003c\/li\u003e\n  \u003cli\u003eFollow Harley torque specs and tightening sequences for heads and rocker covers.\u003c\/li\u003e\n  \u003cli\u003eCheck valve-train clearances and retorque after initial run-in if specified.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho is this for: Motorcycle DIYers, independent mechanics, and restoration shops working on Harley-Davidson EVO Big Twin 1340cc engines from the mid‑1980s through the late‑1990s. If you're performing a head gasket replacement, valve work, or a top-end refresh on compatible Dyna, Softail, or Touring EVO models, this BIGLKNM kit supplies the upper-end gaskets and seals needed to complete the job with OEM-style fitment. Verify your model and year against the fitment list before purchasing to ensure a correct match.\u003c\/p\u003e\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Does this kit include head gaskets for both cylinders?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes — the kit contains head gaskets for both cylinders plus associated base gaskets and seals.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Is this gasket kit compatible with 1996 Low Rider EVO models?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes — it fits 1994–1998 Low Rider EVO variants, but verify your exact model code before purchasing.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"BIGLKNM","offers":[{"title":"Default Title","offer_id":55168490635607,"sku":"B0D967PTR3","price":47.37,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1050\/1524\/7191\/files\/biglknm-front-packaging-top-end-gasket-kit.jpg?v=1790405454","url":"https:\/\/britishgarage.co.uk\/products\/biglknm-top-end-gasket-kit-for-harley-evo-big-twin-1340cc-complete-upper-engine-gaskets-seals","provider":"British Garage","version":"1.0","type":"link"}