{"product_id":"yamaha-yfz450x-98mm-478cc-big-bore-cylinder-kit","title":"Yamaha YFZ450R 98mm 478cc Big Bore Top End Kit CP Piston Cometic 13.5:1 EFI NEW!","description":"\u003cp style=\"text-align: center;\"\u003e\u003cspan style=\"font-size: 0.000001px; color: transparent;\"\u003eYamaha YFZ450R 478cc big bore top end kit with 98mm CP piston, Nikasil cylinder and Cometic gasket for race-ready power. ,21003-1, M1009, C3178, C3178-EST, 20003, M1006, C7908, 71014-5, 2S2-11181-00-00, 3VD-14613-01-00, 94591-57120-00, 2S2-11311-30-00, 4FM-12213-00, 5TG-11631-12-00, 5TG-11633-10-00, 5TG-11631-21-00, M1002, 93450-22027-00, 2S2-11351-00-00\u003c\/span\u003e\u003c\/p\u003e \u003cdiv style=\"max-width:800px;margin:0 auto;font-family:Arial,Helvetica,sans-serif;line-height:1.5;color:#222;\"\u003e \u003ch2 style=\"text-align:center;font-size:26px;margin:0 0 12px 0;\"\u003e \u003cstrong\u003eYamaha YFZ450R \/ YFZ450X 98mm 478cc Big Bore Top End Kit CP Cometic 13.5:1\u003c\/strong\u003e \u003c\/h2\u003e \u003ch3 style=\"color:#c00;margin:20px 0 6px;text-align:center;\"\u003e📖 Product Description\u003c\/h3\u003e \u003cp style=\"text-align:center;\"\u003e\u003cspan style=\"font-size:16px;\"\u003eTransform your EFI Yamaha with the \u003cstrong\u003eBPRATV 98mm 478cc Big Bore Top End Kit\u003c\/strong\u003e engineered for riders who demand aggressive power, instant throttle response, and proven durability. Built around a forged \u003cstrong\u003eCP-Carrillo piston\u003c\/strong\u003e, a performance-plated \u003cstrong\u003eBPRATV Nikasil cylinder\u003c\/strong\u003e, and a precision \u003cstrong\u003eCometic MLS gasket\u003c\/strong\u003e, this kit boosts displacement to 478cc with a race-focused 13.5:1 compression ratio for explosive performance.\u003c\/span\u003e\u003c\/p\u003e \u003ch3 style=\"color:#c00;margin:20px 0 6px;text-align:center;\"\u003e🔥 Key Features \u0026amp; Benefits\u003c\/h3\u003e \u003cp style=\"text-align:center;\"\u003e\u003cspan style=\"font-size:16px;\"\u003eDesigned as a complete, race-ready solution, this big bore kit delivers reliable power gains with OEM-plus fit and finish for high-performance riding and competition use.\u003c\/span\u003e\u003c\/p\u003e \u003cul\u003e \u003cli\u003e\u003cspan style=\"font-size:16px;\"\u003e98mm big bore increases displacement to \u003cstrong\u003e478cc\u003c\/strong\u003e for massive torque gains\u003c\/span\u003e\u003c\/li\u003e \u003cli\u003e\u003cspan style=\"font-size:16px;\"\u003e\u003cstrong\u003e13.5:1 compression\u003c\/strong\u003e for harder hit, stronger midrange, and top-end pull\u003c\/span\u003e\u003c\/li\u003e \u003cli\u003e\u003cspan style=\"font-size:16px;\"\u003e\u003cstrong\u003eCP-Carrillo forged piston\u003c\/strong\u003e for high-RPM stability and long service life\u003c\/span\u003e\u003c\/li\u003e \u003cli\u003e\u003cspan style=\"font-size:16px;\"\u003e\u003cstrong\u003eNikasil-plated cylinder\u003c\/strong\u003e for superior heat transfer and wear resistance\u003c\/span\u003e\u003c\/li\u003e \u003cli\u003e\u003cspan style=\"font-size:16px;\"\u003e\u003cstrong\u003eCometic Top End Gasket Kit with a Big Bore Cometic MLS gasket\u003c\/strong\u003e ensures reliable high-pressure sealing\u003c\/span\u003e\u003c\/li\u003e \u003c\/ul\u003e \u003ch3 style=\"color:#c00;margin:20px 0 6px;text-align:center;\"\u003e✅ Compatibility\u003c\/h3\u003e \u003cp style=\"text-align:center;\"\u003e\u003cspan style=\"font-size:16px;\"\u003ePrecision-engineered for Yamaha fuel-injected 450 sport ATVs using a direct big bore replacement top end.\u003c\/span\u003e\u003c\/p\u003e \u003cul\u003e \u003cli\u003e\u003cspan style=\"font-size:16px;\"\u003eYamaha \u003cstrong\u003eYFZ450R EFI\u003c\/strong\u003e – 2009–2026\u003c\/span\u003e\u003c\/li\u003e \u003cli\u003e\u003cspan style=\"font-size:16px;\"\u003eYamaha \u003cstrong\u003eYFZ450X EFI\u003c\/strong\u003e – All Years\u003c\/span\u003e\u003c\/li\u003e \u003cli\u003e\u003cspan style=\"font-size:16px;\"\u003eReplaces OEM top end with 98mm big bore components\u003c\/span\u003e\u003c\/li\u003e \u003cli\u003e\u003cspan style=\"font-size:16px;\"\u003eDesigned for \u003cstrong\u003erace fuel use\u003c\/strong\u003e due to high compression\u003c\/span\u003e\u003c\/li\u003e \u003cli\u003e\u003cspan style=\"font-size:16px;\"\u003eProfessional installation and EFI tuning recommended\u003c\/span\u003e\u003c\/li\u003e \u003c\/ul\u003e \u003ch3 style=\"color:#c00;margin:20px 0 6px;text-align:center;\"\u003e❓ Frequently Asked Questions (FAQ)\u003c\/h3\u003e \u003cul\u003e \u003cli\u003e\n\u003cspan style=\"font-size:16px;\"\u003e\u003cstrong\u003eQ:\u003c\/strong\u003e Do I need tuning after installing this kit?\u003c\/span\u003e \u003cp style=\"text-align:left;margin:0 0 10px 0;\"\u003e\u003cspan style=\"font-size:16px;\"\u003e\u003cstrong\u003eA:\u003c\/strong\u003e Yes. EFI fuel and ignition mapping must be adjusted for the 98mm 478cc setup.\u003c\/span\u003e\u003c\/p\u003e \u003c\/li\u003e \u003cli\u003e\n\u003cspan style=\"font-size:16px;\"\u003e\u003cstrong\u003eQ:\u003c\/strong\u003e Will this work with a stock cylinder head?\u003c\/span\u003e \u003cp style=\"text-align:left;margin:0 0 10px 0;\"\u003e\u003cspan style=\"font-size:16px;\"\u003e\u003cstrong\u003eA:\u003c\/strong\u003e Yes. It is designed to run with a healthy stock head and valves.\u003c\/span\u003e\u003c\/p\u003e \u003c\/li\u003e \u003cli\u003e\n\u003cspan style=\"font-size:16px;\"\u003e\u003cstrong\u003eQ:\u003c\/strong\u003e Can I run pump gas with this kit?\u003c\/span\u003e \u003cp style=\"text-align:left;margin:0 0 10px 0;\"\u003e\u003cspan style=\"font-size:16px;\"\u003e\u003cstrong\u003eA:\u003c\/strong\u003e No. Due to the 13.5:1 compression ratio, race fuel is required.\u003c\/span\u003e\u003c\/p\u003e \u003c\/li\u003e \u003cli\u003e\n\u003cspan style=\"font-size:16px;\"\u003e\u003cstrong\u003eQ:\u003c\/strong\u003e What warranty is included?\u003c\/span\u003e \u003cp style=\"text-align:left;margin:0 0 10px 0;\"\u003e\u003cspan style=\"font-size:16px;\"\u003e\u003cstrong\u003eA:\u003c\/strong\u003e The cylinder includes a 1-year limited BPRATV warranty; other components carry manufacturer warranties.\u003c\/span\u003e\u003c\/p\u003e \u003c\/li\u003e \u003c\/ul\u003e \u003ch3 style=\"color:#c00;margin:20px 0 6px;text-align:center;\"\u003e🌟 Why Buy from BPRATV? Trusted Performance Experts 🌟\u003c\/h3\u003e \u003cp style=\"text-align:center;margin:0 20px;\"\u003e\u003cspan style=\"font-size:16px;\"\u003eAt BPRATV, our promise is unwavering: \u003cstrong\u003eThe Best Parts. The Best Performance. The Best Price.\u003c\/strong\u003e Every kit is carefully selected and built to deliver proven power, precise fitment, and race-level reliability. Trust BPRATV to keep your Yamaha YFZ450R\/X running at its best, \u003cstrong\u003eevery single time.\u003c\/strong\u003e\u003c\/span\u003e\u003c\/p\u003e \u003cp style=\"text-align:center;margin:0 20px;\"\u003e\u003cspan style=\"font-size:16px;\"\u003e\u003cbr\u003e\u003c\/span\u003e\u003c\/p\u003e \u003cp style=\"text-align:center;margin:0 20px;\"\u003e\u003cspan style=\"color:#38761d;font-size:16px;\"\u003e\u003cstrong\u003e\u003cem\u003eUpgrade your YFZ today and feel the 478cc difference on your next ride.\u003c\/em\u003e\u003c\/strong\u003e\u003c\/span\u003e\u003c\/p\u003e \u003cp style=\"text-align:center;margin:0 20px;\"\u003e\u003cspan style=\"font-size:16px;\"\u003e\u003cbr\u003e\u003c\/span\u003e\u003c\/p\u003e \u003cp style=\"text-align:center;margin:0 20px;\"\u003e\u003cspan style=\"color:#0000ff;font-size:16px;\"\u003e\u003cstrong\u003eBPRATV - The Best Parts. The Best Performance. The Best Price.\u003c\/strong\u003e\u003c\/span\u003e\u003c\/p\u003e \u003cp style=\"text-align:center;margin:0 20px;\"\u003e\u003cspan style=\"color:#0000ff;font-size:16px;\"\u003e\u003cstrong\u003eBRAPPPPPPPPPP!\u003c\/strong\u003e\u003c\/span\u003e\u003c\/p\u003e \u003cp style=\"text-align:center;font-size:10px;color:#555;margin:20px 0 0px;\"\u003e© BPRATV LLC 1-year limited warranty from the manufacturer for material or workmanship defects.*\u003cbr\u003e\u003cbr\u003e Due to the nature of high performance and racing applications, BPRATV LLC components are sold without express warranty or any implied warranty of merchantability or fitness for a specific purpose. BPRATV LLC shall not, under any circumstances, be liable for any specific, incidental or consequential damages, including, but not limited to, damage, or loss of property or equipment, loss of profits or revenue(s), cost of purchased or replacement goods, or claims of customers of the purpose, which may arise and\/or shall result from sale, installation or use of these parts. Installation of these parts may void vehicle manufacturers warranty coverage and\/or may cause the vehicle to be illegal in some locations.\u003cbr\u003e\u003cbr\u003e This product is exempt from the emission standards and related requirements of 40 C.F.R. § 1051 as provided by 40 C.F.R. § 1051.620, and California law. This product is sold only for use in connection with EPA-certified, purpose-built, nonroad competition vehicles and is not legal for use on public highways.\u003c\/p\u003e\n\u003cp style=\"text-align:center;font-size:10px;color:#555;margin:20px 0 0px;\"\u003e\u003c\/p\u003e \u003c\/div\u003e \u003c!-- EBAY TITLES (79–80 CHARACTERS) 1. Yamaha YFZ450R 98mm 478cc Big Bore Top End Kit CP Piston Cometic 13.5:1 2. YFZ450R YFZ450X 478cc Big Bore Kit 98mm CP Piston Cylinder Cometic 3. Yamaha YFZ450R EFI 98mm Big Bore Top End 478cc CP 13.5:1 Kit 4. YFZ450X YFZ450R Big Bore 98mm 478cc Top End CP Piston Kit 5. Yamaha YFZ450R 478cc Big Bore Cylinder Kit 98mm CP Cometic 6. YFZ450R EFI 98mm Big Bore Top End Rebuild Kit CP Carrillo 7. Yamaha YFZ450X 478cc Big Bore 98mm Top End CP Piston Kit 8. YFZ450R Racing 98mm Big Bore Top End 478cc CP Cometic Kit 9. Yamaha YFZ450R Performance 478cc Big Bore 98mm Top End Kit 10. YFZ450R YFZ450X CP 98mm 478cc Big Bore Cylinder Top End Kit EBAY KEYWORDS yfz450r big bore kit yfz450x 478cc 98mm big bore yfz450r cp piston yfz450r yfz450r top end kit yfz450 big bore cylinder yfz450r racing engine kit yfz450r rebuild kit yfz450x big bore yfz450r 98mm SEO KEYWORDS Yamaha YFZ450R 478cc big bore kit YFZ450R 98mm CP piston kit YFZ450X big bore top end YFZ450R performance engine upgrade YFZ450R racing big bore kit YFZ450 EFI big bore YFZ450R cylinder piston kit YFZ450R high compression piston YFZ450R engine rebuild kit YFZ450R race motor parts META TITLES Yamaha YFZ450R 478cc Big Bore Top End Kit 98mm CP 13.5:1 YFZ450R \/ YFZ450X 98mm 478cc Big Bore Kit CP Piston YFZ450R EFI Big Bore 478cc Top End Performance Kit Yamaha YFZ450R 98mm Big Bore Racing Top End Kit YFZ450R 478cc Big Bore Cylinder CP Piston Kit META DESCRIPTIONS Yamaha YFZ450R 478cc big bore top end kit with 98mm CP piston, Nikasil cylinder and Cometic gasket for race-ready power. Upgrade your YFZ450R or YFZ450X with a 98mm 478cc big bore kit delivering high compression performance and durability. Race-proven YFZ450R big bore top end kit featuring CP piston, Cometic MLS gasket and Nikasil cylinder. Get massive torque and throttle response with this Yamaha YFZ450R 98mm 478cc big bore top end kit. High compression 13.5:1 YFZ450R big bore kit built for competition and serious performance riders. URL HANDLES yamaha-yfz450r-98mm-478cc-big-bore-top-end-kit yamaha-yfz450x-98mm-478cc-big-bore-cylinder-kit yfz450r-cp-piston-98mm-478cc-top-end-kit yfz450r-yfz450x-478cc-big-bore-performance-kit yamaha-yfz450r-efi-98mm-big-bore-racing-kit --\u003e","brand":"CP-Carrillo","offers":[{"title":"Default Title","offer_id":45644254118085,"sku":"287080466719\/21003\/M1085\/C3178\/JT","price":444.44,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0593\/1083\/3861\/files\/yfz450r-yfz-450r-98mm-98-478cc-cp-cometic-big-bore-top-end-cylinder-kit_e89b0400-f31b-4d16-b5b9-9fd9a88f9ef6.png?v=1768610959","url":"https:\/\/bpratv.com\/products\/yamaha-yfz450x-98mm-478cc-big-bore-cylinder-kit","provider":"BPRATV","version":"1.0","type":"link"}