{"product_id":"namura-na-10040-4k-top-end-kit-85-97-mm-11-1-compression-for-honda-rancher-trx400fa-and-trx400fga","title":"NAMURA NA-10040-4K Top End Kit 85.97 mm, 11:1 Compression for Honda Rancher TRX400FA and TRX400FGA","description":"\u003cp\u003eThe NAMURA NA-10040-4K Top End Kit is designed for Honda Rancher all-terrain vehicles requiring an 85.97 mm, plus 1.00 mm piston with an 11:1 compression ratio. This comprehensive kit includes the piston, piston rings, wrist pin, retaining clips, top end bearing, and gasket kit for a convenient top-end rebuild. The kit is engineered for dependable fitment and performance on select 2004–2007 Honda TRX400FA Rancher AT [SRA] and TRX400FGA Rancher AT GPScape [SRA] models.\u003c\/p\u003e\u003cp\u003eThe piston features NAMURA’s MOS2, or Teflon\/Molybdenum, coated skirts. The rolled-on coating process creates a durable bond while helping reduce friction, improve heat transfer, and minimize the risk of cold seizures. Machined smooth heads help reflect combustion heat and reduce carbon buildup, supporting piston protection and consistent engine operation. Anodized domes further improve heat resistance and durability compared with non-anodized piston domes.\u003c\/p\u003e\u003cp\u003eNAMURA uses a hypereutectic casting process to provide increased silicon content, reduced thermal expansion, and improved wear resistance. This construction is suited to engines exposed to elevated cylinder temperatures and demanding operating conditions. Verify the bore size, compression specification, and engine configuration before installation. Manufacturer part number NA-10040-4K and vendor part number 186-10404 identify this application-specific top end kit.\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\u003eApplication: Designed for 2004–2007 Honda TRX400FA Rancher AT [SRA] and TRX400FGA Rancher AT GPScape [SRA] models\u003c\/li\u003e\n\u003cli\u003ePiston Size: 85.97 mm, plus 1.00 mm oversize, with an 11:1 compression ratio\u003c\/li\u003e\n\u003cli\u003eMOS2 Coated Skirts: Rolled-on Teflon\/Molybdenum coating helps reduce friction, improve heat transfer, and minimize cold-seizure risk\u003c\/li\u003e\n\u003cli\u003eMachined Smooth Head: Helps reflect combustion heat and reduce carbon buildup on the piston top\u003c\/li\u003e\n\u003cli\u003eAnodized Dome: Improves heat resistance and durability for demanding engine conditions\u003c\/li\u003e\n\u003cli\u003eHypereutectic Construction: Higher silicon content helps reduce expansion and improve wear resistance\u003c\/li\u003e\n\u003cli\u003eBrand and Part Number: NAMURA NA-10040-4K; vendor part number 186-10404\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\nFitment:\u003cbr\u003e\n2004 Honda TRX400FA Rancher AT [SRA]\u003cbr\u003e\n2004 Honda TRX400FGA Rancher AT GPScape [SRA]\u003cbr\u003e\n2005 Honda TRX400FA Rancher AT [SRA]\u003cbr\u003e\n2005 Honda TRX400FGA Rancher AT GPScape [SRA]\u003cbr\u003e\n2006 Honda TRX400FA Rancher AT [SRA]\u003cbr\u003e\n2006 Honda TRX400FGA Rancher AT GPScape [SRA]\u003cbr\u003e\n2007 Honda TRX400FA Rancher AT [SRA]\u003cbr\u003e\n2007 Honda TRX400FGA Rancher AT GPScape [SRA]","brand":"NAMURA","offers":[{"title":"Default Title","offer_id":67559268319467,"sku":"186-10404","price":140.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0611\/3882\/9547\/files\/dd77-572a583cd9540_a4f7cdbd-4bf0-4543-99e4-ea87f26b9f62.jpg?v=1790771512","url":"https:\/\/ctracingservices.com\/products\/namura-na-10040-4k-top-end-kit-85-97-mm-11-1-compression-for-honda-rancher-trx400fa-and-trx400fga","provider":"Cascade Tire \u0026 Racing Services","version":"1.0","type":"link"}