{"product_id":"namura-na-50001-2k-top-end-kit-80-45-mm-0-50-mm-11-1-for-polaris-trail-boss-350l","title":"NAMURA NA-50001-2K Top End Kit 80.45 mm +0.50 mm 11:1 for Polaris Trail Boss 350L","description":"\u003cp\u003eRestore top-end performance with the NAMURA NA-50001-2K Top End Kit, designed for select Polaris Trail Boss 350L 2X4 and 4X4 models. This kit features an 80.45 mm piston with a +0.50 mm oversize specification and an 11:1 compression ratio. It includes the piston, rings, wrist pin, retaining clips, top-end bearing, and gasket kit for a comprehensive engine rebuild solution.\u003c\/p\u003e\u003cp\u003eThe piston uses a hypereutectic casting process to provide increased silicon content, reduced expansion, improved wear resistance, and reliable performance at higher cylinder temperatures. MOS2, or Teflon\/Molybdenum, coated skirts are applied using a rolled-on process that creates a strong bond while helping reduce friction, improve heat transfer, and minimize the risk of cold seizures. The machined smooth head reflects combustion heat and helps reduce carbon buildup, supporting piston protection and efficient engine operation.\u003c\/p\u003e\u003cp\u003eAn anodized dome increases heat resistance and durability, providing added protection during demanding riding conditions. The NAMURA NA-50001-2K Top End Kit fits 1990, 1991, 1992, and 1993 Polaris Trail Boss 350L 2X4 models, as well as 1990, 1991, 1992, and 1993 Polaris Trail Boss 350L 4X4 models. Verify the cylinder bore, required oversize, compression ratio, and engine application 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\u003e80.45 mm +0.50 mm piston: Provides the specified oversize fit for compatible Polaris Trail Boss 350L applications\u003c\/li\u003e\n\u003cli\u003e11:1 compression ratio: Supports the intended performance configuration for the listed engine fitments\u003c\/li\u003e\n\u003cli\u003eMOS2-coated skirts: Helps reduce friction, improve heat transfer, and minimize cold-seizure risk\u003c\/li\u003e\n\u003cli\u003eMachined smooth head: Reflects combustion heat and helps reduce carbon buildup on the piston crown\u003c\/li\u003e\n\u003cli\u003eAnodized dome: Improves heat resistance and durability under demanding operating conditions\u003c\/li\u003e\n\u003cli\u003eHypereutectic casting: Provides reduced expansion, increased wear resistance, and improved high-temperature capability\u003c\/li\u003e\n\u003cli\u003eFitment: Fits 1990-1993 Polaris Trail Boss 350L 2X4 and 4X4 models\u003c\/li\u003e\n\u003c\/ul\u003e\u003cbr\u003e\nFitment:\u003cbr\u003e\n1990 Polaris Trail Boss 350L 2X4\u003cbr\u003e\n1990 Polaris Trail Boss 350L 4X4\u003cbr\u003e\n1991 Polaris Trail Boss 350L 2X4\u003cbr\u003e\n1991 Polaris Trail Boss 350L 4X4\u003cbr\u003e\n1992 Polaris Trail Boss 350L 2X4\u003cbr\u003e\n1992 Polaris Trail Boss 350L 4X4\u003cbr\u003e\n1993 Polaris Trail Boss 350L 2X4\u003cbr\u003e\n1993 Polaris Trail Boss 350L 4X4","brand":"NAMURA","offers":[{"title":"Default Title","offer_id":67558791151851,"sku":"186-50012","price":128.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0611\/3882\/9547\/files\/dd77-572a583cd9540_b53cd573-f1de-45b7-8cae-4bf5ef39622e.jpg?v=1790768981","url":"https:\/\/ctracingservices.com\/products\/namura-na-50001-2k-top-end-kit-80-45-mm-0-50-mm-11-1-for-polaris-trail-boss-350l","provider":"Cascade Tire \u0026 Racing Services","version":"1.0","type":"link"}