{"product_id":"wossner-8957db-76-97mm-piston-kit-14-0-1-2019-2025-yamaha-yz250f-fx-wr250f","title":"Wossner 8957DB 76.97mm Piston Kit 14.0:1 2019-2025 Yamaha YZ250F\/FX WR250F","description":"\u003cp\u003eRestore peak power and precision to your engine with the \u003cstrong\u003eWossner 8957DB Premium Series Piston Kit\u003c\/strong\u003e. Specifically engineered for \u003cstrong\u003ehigh-performance Yamaha 250cc four-strokes\u003c\/strong\u003e, this \u003cstrong\u003eSize B (76.97mm)\u003c\/strong\u003e piston is the ideal choice for riders looking for a tighter fit in a slightly worn cylinder to maintain maximum compression. At \u003cstrong\u003eMoto-House MX\u003c\/strong\u003e, we understand that \u003cstrong\u003eRacing Performance\u003c\/strong\u003e depends on exact tolerances, and this \u003cstrong\u003eforged aluminum alloy piston\u003c\/strong\u003e delivers the durability required for professional motocross competition.\u003c\/p\u003e\n\u003cp\u003eThe Wossner 8957DB features a \u003cstrong\u003edouble-bridge forging design\u003c\/strong\u003e and a \u003cstrong\u003e3D crown\u003c\/strong\u003e to withstand the high-heat environments of modern racing. This kit is optimized with a \u003cstrong\u003e14.0:1 compression ratio\u003c\/strong\u003e, providing an immediate boost in throttle response and low-end torque. Designed with \u003cstrong\u003eskirt coatings for reduced friction\u003c\/strong\u003e, this piston ensures a smoother \u003cstrong\u003eengine break-in period\u003c\/strong\u003e while the \u003cstrong\u003eenhanced piston pin oiling slots\u003c\/strong\u003e provide critical lubrication to the wrist pin under extreme RPMs.\u003c\/p\u003e\n\u003ch3\u003eTop Features: Wossner 8957DB Piston Kit\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDouble Bridge Forging:\u003c\/strong\u003e High-strength, \u003cstrong\u003elightweight forged construction\u003c\/strong\u003e for superior structural integrity.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e14.0:1 Compression Ratio:\u003c\/strong\u003e Delivers elite \u003cstrong\u003e4-stroke power gains\u003c\/strong\u003e and optimized combustion.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize B (76.97mm):\u003c\/strong\u003e Designed for \u003cstrong\u003eprecision piston-to-wall clearance\u003c\/strong\u003e to ensure a quieter, more efficient engine.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAdvanced Skirt Coating:\u003c\/strong\u003e Reduces parasitic drag and provides \u003cstrong\u003eimproved wear resistance\u003c\/strong\u003e.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eComplete Top-End Kit:\u003c\/strong\u003e Includes the \u003cstrong\u003e76.97mm piston\u003c\/strong\u003e, \u003cstrong\u003ehigh-performance rings\u003c\/strong\u003e, wrist pin, and clips for a total \u003cstrong\u003eOEM replacement upgrade\u003c\/strong\u003e.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eFitment List\u003c\/h3\u003e\n\u003ctable border=\"1\" style=\"width: 100%; border-collapse: collapse;\"\u003e\n\u003cthead\u003e\n\u003ctr style=\"background-color: #f2f2f2;\"\u003e\n\u003cth style=\"padding: 8px; text-align: left;\"\u003eYear Range\u003c\/th\u003e\n\u003cth style=\"padding: 8px; text-align: left;\"\u003eVehicle Brand\u003c\/th\u003e\n\u003cth style=\"padding: 8px; text-align: left;\"\u003eVehicle Model \u0026amp; Size\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px;\"\u003e2019-2025\u003c\/td\u003e\n\u003ctd style=\"padding: 8px;\"\u003eYamaha\u003c\/td\u003e\n\u003ctd style=\"padding: 8px;\"\u003eYZ250F\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px;\"\u003e2020-2025\u003c\/td\u003e\n\u003ctd style=\"padding: 8px;\"\u003eYamaha\u003c\/td\u003e\n\u003ctd style=\"padding: 8px;\"\u003eYZ250FX\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px;\"\u003e2020-2025\u003c\/td\u003e\n\u003ctd style=\"padding: 8px;\"\u003eYamaha\u003c\/td\u003e\n\u003ctd style=\"padding: 8px;\"\u003eWR250F\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the difference between Size A and Size B pistons?\u003c\/strong\u003e\u003cbr\u003eSize B (76.97mm) is slightly larger than Size A. It is used to maintain a \u003cstrong\u003etight piston-to-wall clearance\u003c\/strong\u003e as the cylinder bore naturally wears, ensuring better \u003cstrong\u003ering seal and oil control\u003c\/strong\u003e.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes this kit include everything needed for a top-end rebuild?\u003c\/strong\u003e\u003cbr\u003eYes, this is a \u003cstrong\u003ecomplete piston kit\u003c\/strong\u003e including the \u003cstrong\u003eforged piston\u003c\/strong\u003e, \u003cstrong\u003ehigh-tension rings\u003c\/strong\u003e, wrist pin, and retaining clips.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIs the 14.0:1 compression ratio safe for pump gas?\u003c\/strong\u003e\u003cbr\u003eThis ratio is designed for \u003cstrong\u003ehigh-performance racing\u003c\/strong\u003e; while it may run on high-quality pump premium, many racers prefer a race-gas blend to maximize the \u003cstrong\u003eperformance gains\u003c\/strong\u003e and prevent detonation.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eUpgrade Your Ride\u003c\/strong\u003e with the industry's leading forging technology. Buy the \u003cstrong\u003eWossner 8957DB Piston Kit\u003c\/strong\u003e today from \u003cstrong\u003eMoto-House MX\u003c\/strong\u003e.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eMoto-House MX\u003c\/strong\u003e – \u003cstrong\u003eChoice of Champions\u003c\/strong\u003e – is located in Clermont\/Montverde, FL. The best motocross shop in Central Florida.\u003c\/p\u003e","brand":"WOSSNER","offers":[{"title":"Default Title","offer_id":44174189559891,"sku":"8957DB","price":184.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1754\/5421\/files\/1490907.png?v=1772930888","url":"https:\/\/motohousemx.com\/products\/wossner-8957db-76-97mm-piston-kit-14-0-1-2019-2025-yamaha-yz250f-fx-wr250f","provider":"Moto-House MX","version":"1.0","type":"link"}