{"product_id":"syiono-primary-cover-gasket-seal-kit-for-harley-twin-cam-1999-2006-complete-o-ring-mainshaft-inspection-gaskets","title":"Syiono Primary Cover Gasket \u0026 Seal Kit for Harley Twin Cam 1999–2006 — Complete O‑ring, Mainshaft \u0026 Inspection Gaskets","description":"\u003cp\u003e\u003cstrong\u003eSyiono Primary Cover Gasket Clutch Inspection Seal Kit is a complete replacement gasket and seal set engineered to reseal the primary cover and inspection ports on 1999–2006 Harley-Davidson Twin Cam FLH\/T Touring and Electra Glide\/Road Glide\/Road King models.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eThis kit gathers every commonly replaced O-ring, oil seal, mainshaft seal and primary\/inspection gasket you need when servicing the primary cover on Twin Cam Touring Harleys from 1999 through 2006. Rather than hunting multiple part numbers, the Syiono kit provides the seals and gaskets matched to the original fitment so you can restore a leak-free primary case and properly protect the clutch assembly from oil intrusion. Each component in the package is molded from durable material selected to match OEM sealing properties and to withstand the heat and oil exposure common in primary housings.\u003c\/p\u003e\n\n\u003ch3\u003eWhich specific parts are included in the kit?\u003c\/h3\u003e\n\u003cp\u003eThe Syiono kit consolidates the common replacement pieces required for a primary cover service on supported Harley models. It contains O-rings, oil seals, mainshaft seals and several gaskets used around the derby, inspection cover and primary cover.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e11147 O-Ring for specified sealing points\u003c\/li\u003e\n  \u003cli\u003e12052A oil seal and 12066 mainshaft seal\u003c\/li\u003e\n  \u003cli\u003e25416-99C derby\/clutch cover gasket\u003c\/li\u003e\n  \u003cli\u003e34906-85 series inspection gaskets and 34901-94 series primary gaskets plus locating screw gasket\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow does this kit help when replacing a leaking primary cover?\u003c\/h3\u003e\n\u003cp\u003eReplacing worn seals and gaskets is the standard way to stop leaks and restore correct oil containment in the primary housing. Using fresh, correctly fitted seals reduces the chance of oil seeping into the clutch or dripping externally, which helps maintain clutch function and keeps the bike cleaner.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eReplaces degraded or flattened gaskets that no longer compress properly\u003c\/li\u003e\n  \u003cli\u003eFits OEM-style grooves and bolt patterns to ensure proper seating\u003c\/li\u003e\n  \u003cli\u003ePrevents oil migration into the clutch or onto the ground\u003c\/li\u003e\n  \u003cli\u003eAllows you to reuse a good primary cover instead of buying expensive replacement covers\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWill these seals fit my Harley model and engine year?\u003c\/h3\u003e\n\u003cp\u003eThe kit is specified for 1999–2006 Touring models equipped with the Twin Cam engine family, including FLH and T-series baggers and common variants like Electra Glide, Road Glide and Road King. Cross-check the part numbers in the list with your service manual or existing parts to confirm fitment before installation.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eCompatible with Harley-Davidson FLH\/T Twin Cam Touring models 1999–2006\u003c\/li\u003e\n  \u003cli\u003eIncludes part numbers used on Dyna, FXD and FLSTF\/FXST Twin Cam bagger applications\u003c\/li\u003e\n  \u003cli\u003eNot intended for non-Twin-Cam or significantly modified primary housings\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat should I expect during installation and service intervals?\u003c\/h3\u003e\n\u003cp\u003eInstall the kit during a primary cover service when you replace clutch plates, inspect the chain\/torque assembly, or whenever you discover oil leaks. Proper cleaning of mating surfaces and using correct torque on fasteners are essential for a long-lasting seal. If you find corrosion or warpage on the mating surface, consider machining or replacing the cover before fitting new gaskets.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eClean mating surfaces and remove old gasket material before installation\u003c\/li\u003e\n  \u003cli\u003eApply proper sealants only where specified by the manual; avoid over-application\u003c\/li\u003e\n  \u003cli\u003eTorque bolts to factory specs and recheck after initial heat cycles\u003c\/li\u003e\n  \u003cli\u003eInspect seals periodically for damage during routine maintenance\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho is this for: The Syiono Primary Cover Gasket Clutch Inspection Seal Kit is aimed at DIY mechanics, independent motorcycle technicians and restoration shops working on 1999–2006 Harley-Davidson Twin Cam Touring bikes. If you are planning a primary cover service, clutch job, or troubleshooting oil leaks around the primary housing, this kit supplies the common replacement seals and gaskets to complete the repair with OEM-compatible parts.\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 fit all 1999–2006 Harley Touring Twin Cam models?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes, it covers common Twin Cam FLH\/T Touring models 1999–2006, but verify part numbers against your bike before purchasing.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Are these OEM parts or aftermarket replacements?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: These are aftermarket replacement seals and gaskets designed to match OEM fit and function for primary cover service.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"Syiono","offers":[{"title":"Default Title","offer_id":48086026616990,"sku":"B0FDGWLGXS","price":49.98,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0781\/2041\/9486\/files\/syiono-primary-cover-kit-box-front.jpg?v=1785882152","url":"https:\/\/northtrailauto.ca\/products\/syiono-primary-cover-gasket-seal-kit-for-harley-twin-cam-1999-2006-complete-o-ring-mainshaft-inspection-gaskets","provider":"North Trail Auto","version":"1.0","type":"link"}