{"product_id":"athena-p400485100032-290cc-big-bore-cylinder-kit-83mm-bore-high-performance-forged-piston-upgrade-converts-250cc-to-290cc-compatible-with-yamaha-wr250r-wr250x-2008-2021","title":"Athena P400485100032 290cc Big Bore Cylinder Kit (83mm Bore) - High-Performance Forged Piston Upgrade, Converts 250cc to 290cc, Compatible with Yamaha WR250R \u0026 WR250X (2008-2021)","description":"UPGRADE YOUR RIDE TO THE NEXT LEVEL OF PERFORMANCE Extract massive power, aggressive low-end torque, and unmatched acceleration from your 250cc four-stroke engine with the Athena Big Bore Cylinder Kit (Part No. P400485100032), a premium race-proven package engineered in Italy to seamlessly convert your factory dual-sport setup into a high-revving, high-output 290cc powerhouse. Entirely cast from high-grade aluminum and treated with a specialized Motor-Nicksil (Nickel-Silicon) coating, this cylinder guarantees exceptional thermal dissipation, minimal friction, and optimal wear resistance to deliver a substantial increase along the entire power curve while maintaining strict original-equipment reliability. This complete bolt-on kit comes loaded with everything required for a flawless installation—including a widened water-jacket aluminum cylinder, a high-performance forged piston coated with molybdenum, premium rings, wrist pin, clips, and a specific high-tightness multi-layer gasket set—allowing you to dramatically increase street, trail, and track performance without requiring any complex machining or structural modifications to your factory crankcase.","brand":"Athena","offers":[{"title":"Default Title","offer_id":52666019971359,"sku":"P400485100032","price":1251.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0813\/2195\/1519\/files\/P400485100032-1.jpg?v=1783601434","url":"https:\/\/massdepot.com\/products\/athena-p400485100032-290cc-big-bore-cylinder-kit-83mm-bore-high-performance-forged-piston-upgrade-converts-250cc-to-290cc-compatible-with-yamaha-wr250r-wr250x-2008-2021","provider":"Mass Depot","version":"1.0","type":"link"}