{"product_id":"namura-na-40006k-top-end-kit-83-mm-standard-11-1-for-yamaha-yfm400fa-kodiak-and-yfm400fb-big-bear","title":"NAMURA NA-40006K Top End Kit 83 mm Standard 11:1 for Yamaha YFM400FA Kodiak and YFM400FB Big Bear","description":"\u003cp\u003eRestore top-end performance with the NAMURA NA-40006K Top End Kit, designed for select Yamaha YFM400FA Kodiak 4WD and YFM400FB Big Bear 4WD models. This 83 mm standard-bore, 11:1 compression kit includes the essential components needed for a reliable top-end rebuild: piston, piston rings, wrist pin, wrist-pin clips, top-end bearing, and gasket kit. It is engineered for direct fitment on the applicable Yamaha ATV applications listed below.\u003c\/p\u003e\u003cp\u003eThe piston uses a hypereutectic casting process that increases silicon content to help control expansion, improve wear resistance, and withstand elevated cylinder temperatures. Its MOS2, or Teflon\/molybdenum, coated skirts use a rolled-on application process for a strong coating bond. This finish helps reduce friction, improve heat transfer, and minimize the risk of cold seizures during operation. The machined-smooth piston head helps reflect combustion heat and reduce carbon buildup, while the anodized dome improves heat resistance and durability.\u003c\/p\u003e\u003cp\u003eFitment includes 1993–1995 Yamaha YFM400FA Kodiak 4WD with SRA and 2000–2006 Yamaha YFM400FB Big Bear 4WD with SRA. Verify the year, model, bore specification, and compression ratio before installation. Manufactured by NAMURA, this top-end kit is a practical replacement solution for rebuilding the upper engine assembly and supporting dependable ATV performance.\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, clips, top-end bearing, and gasket kit\u003c\/li\u003e\n\u003cli\u003e83 mm standard-bore piston with an 11:1 compression ratio for applicable Yamaha ATV engines\u003c\/li\u003e\n\u003cli\u003eMOS2 Teflon\/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 dome increases heat resistance and piston durability\u003c\/li\u003e\n\u003cli\u003eHypereutectic casting process provides controlled expansion, wear resistance, and improved high-temperature capability\u003c\/li\u003e\n\u003cli\u003eFits 1993–1995 Yamaha YFM400FA Kodiak 4WD with SRA\u003c\/li\u003e\n\u003cli\u003eFits 2000–2006 Yamaha YFM400FB Big Bear 4WD with SRA\u003c\/li\u003e\n\u003cli\u003eBrand: NAMURA\u003c\/li\u003e\n\u003cli\u003eManufacturer part number: NA-40006K\u003c\/li\u003e\n\u003cli\u003eVendor part number: 186-4006\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\nFitment:\u003cbr\u003e\n1993 Yamaha YFM400FA Kodiak 4WD [SRA]\u003cbr\u003e\n1994 Yamaha YFM400FA Kodiak 4WD [SRA]\u003cbr\u003e\n1995 Yamaha YFM400FA Kodiak 4WD [SRA]\u003cbr\u003e\n1996 Yamaha YFM400FA Kodiak 4WD [SRA]\u003cbr\u003e\n1997 Yamaha YFM400FA Kodiak 4WD [SRA]\u003cbr\u003e\n1998 Yamaha YFM400FA Kodiak 4WD [SRA]\u003cbr\u003e\n1999 Yamaha YFM400FA Kodiak 4WD [SRA]\u003cbr\u003e\n2000 Yamaha YFM400 Big Bear 2WD [SRA]\u003cbr\u003e\n2000 Yamaha YFM400FB Big Bear 4WD [SRA]\u003cbr\u003e\n2001 Yamaha YFM400 Big Bear 2WD [SRA]\u003cbr\u003e\n2001 Yamaha YFM400FB Big Bear 4WD [SRA]\u003cbr\u003e\n2002 Yamaha YFM400 Big Bear 2WD [SRA]\u003cbr\u003e\n2002 Yamaha YFM400FB Big Bear 4WD [SRA]\u003cbr\u003e\n2003 Yamaha YFM400 Big Bear 2WD [SRA]\u003cbr\u003e\n2003 Yamaha YFM400FB Big Bear 4WD [SRA]\u003cbr\u003e\n2004 Yamaha YFM400 Big Bear 2WD [SRA]\u003cbr\u003e\n2004 Yamaha YFM400FB Big Bear 4WD [SRA]\u003cbr\u003e\n2005 Yamaha YFM400FB Big Bear 4WD [SRA]\u003cbr\u003e\n2006 Yamaha YFM400FB Big Bear 4WD [SRA]\u003cbr\u003e\n2007 Yamaha YFM400FBI Big Bear 4WD [IRS]\u003cbr\u003e\n2008 Yamaha YFM400FBI Big Bear 4WD [IRS]\u003cbr\u003e\n2009 Yamaha YFM400FBI Big Bear 4WD [IRS]\u003cbr\u003e\n2010 Yamaha YFM400FBI Big Bear 4WD [IRS]","brand":"NAMURA","offers":[{"title":"Default Title","offer_id":67559046545643,"sku":"186-4006","price":122.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0611\/3882\/9547\/files\/92b5-5e99b68d19a74.jpg?v=1790769871","url":"https:\/\/ctracingservices.com\/products\/namura-na-40006k-top-end-kit-83-mm-standard-11-1-for-yamaha-yfm400fa-kodiak-and-yfm400fb-big-bear","provider":"Cascade Tire \u0026 Racing Services","version":"1.0","type":"link"}