{"product_id":"namura-na-10003k-high-compression-top-end-kit-for-honda-trx400x-and-trx400ex-sportrax","title":"NAMURA NA-10003K High-Compression Top End Kit for Honda TRX400X and TRX400EX Sportrax","description":"\u003cp\u003eThe NAMURA NA-10003K High-Compression Top End Kit is designed for select Honda TRX400X and TRX400EX Sportrax models. This complete top-end replacement kit includes a piston, piston rings, wrist pin, retaining clips, top-end bearing, and gasket kit for a convenient engine rebuild solution. The kit features an 11:1 compression ratio and a standard bore piston engineered for dependable performance and proper fitment on compatible Honda ATV applications.\u003c\/p\u003e\u003cp\u003eNAMURA uses a hypereutectic casting process to provide increased silicon content, helping reduce thermal expansion while improving wear resistance and durability under elevated cylinder temperatures. The piston skirts feature a MOS2 coating made with Teflon and molybdenum. This rolled-on coating process creates a stronger bond than conventional spray-on coatings, helping reduce friction, improve heat transfer, and minimize the risk of cold seizures during operation.\u003c\/p\u003e\u003cp\u003eThe machined smooth piston head helps reflect combustion heat and limit carbon buildup, while the anodized dome improves heat resistance and overall piston durability. These design features support consistent engine operation and long-lasting service when installed with the correct components and manufacturer-recommended procedures. The NAMURA NA-10003K fits 2012–2014 Honda TRX400X models and 1999–2005 Honda TRX400EX Sportrax models. Verify the vehicle year, model, bore specification, and engine configuration before installation.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eComplete top-end kit includes piston, rings, wrist pin, retaining clips, top-end bearing, and gasket kit\u003c\/li\u003e\n\u003cli\u003eStandard bore piston with an 11:1 compression ratio for compatible Honda ATV engines\u003c\/li\u003e\n\u003cli\u003eMOS2 Teflon and molybdenum-coated skirts help reduce friction, improve heat transfer, and minimize cold-seizure risk\u003c\/li\u003e\n\u003cli\u003eMachined smooth piston head helps reflect combustion heat and reduce carbon buildup\u003c\/li\u003e\n\u003cli\u003eAnodized piston dome improves heat resistance and durability\u003c\/li\u003e\n\u003cli\u003eHypereutectic casting process provides reduced expansion, increased wear resistance, and improved performance at higher cylinder temperatures\u003c\/li\u003e\n\u003cli\u003eFits 2012–2014 Honda TRX400X and 1999–2005 Honda TRX400EX Sportrax models\u003c\/li\u003e\n\u003cli\u003eBrand: NAMURA\u003c\/li\u003e\n\u003cli\u003eManufacturer part number: NA-10003K\u003c\/li\u003e\n\u003cli\u003eVendor part number: 186-1003\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\nFitment:\u003cbr\u003e\n1996 Honda XR400R\u003cbr\u003e\n1997 Honda XR400R\u003cbr\u003e\n1998 Honda XR400R\u003cbr\u003e\n1999 Honda TRX400EX Sportrax\u003cbr\u003e\n1999 Honda XR400R\u003cbr\u003e\n2000 Honda TRX400EX Sportrax\u003cbr\u003e\n2000 Honda XR400R\u003cbr\u003e\n2001 Honda TRX400EX Sportrax\u003cbr\u003e\n2001 Honda XR400R\u003cbr\u003e\n2002 Honda TRX400EX Sportrax\u003cbr\u003e\n2002 Honda XR400R\u003cbr\u003e\n2003 Honda TRX400EX Sportrax\u003cbr\u003e\n2003 Honda XR400R\u003cbr\u003e\n2004 Honda TRX400EX Sportrax\u003cbr\u003e\n2004 Honda XR400R\u003cbr\u003e\n2005 Honda TRX400EX Sportrax\u003cbr\u003e\n2006 Honda TRX400EX Sportrax\u003cbr\u003e\n2007 Honda TRX400EX Sportrax\u003cbr\u003e\n2008 Honda TRX400EX Sportrax\u003cbr\u003e\n2009 Honda TRX400EX Sportrax\u003cbr\u003e\n2012 Honda TRX400X\u003cbr\u003e\n2013 Honda TRX400X\u003cbr\u003e\n2014 Honda TRX400X","brand":"NAMURA","offers":[{"title":"Default Title","offer_id":67559339098347,"sku":"186-1003","price":140.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0611\/3882\/9547\/files\/e3ca-5d76d551cadf1_6855c035-9db7-4bff-b6b4-65435c306963.jpg?v=1790772130","url":"https:\/\/ctracingservices.com\/products\/namura-na-10003k-high-compression-top-end-kit-for-honda-trx400x-and-trx400ex-sportrax","provider":"Cascade Tire \u0026 Racing Services","version":"1.0","type":"link"}