{"product_id":"4-valve-cylinder-head","title":"4 Valve Cylinder Head","description":"\u003cp\u003e\u003c\/p\u003e\u003ch2\u003eKOSO 4 Valve Cylinder Head — High-Flow Performance Upgrade\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eUpgrade your Koso 170cc Big Bore kit\u003c\/strong\u003e with the KOSO 4 Valve Cylinder Head. Engineered for increased airflow and combustion efficiency, this 4-valve design delivers noticeable gains in both power and torque for Honda Grom® applications fitted with the Koso big bore kit.\u003c\/p\u003e\n\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHigh-flow 4-valve layout\u003c\/strong\u003e for improved intake and exhaust efficiency\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eForged piston\u003c\/strong\u003e included for enhanced strength and durability\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eStainless steel valves\u003c\/strong\u003e: 24 mm intake and 20 mm exhaust for reliable performance\u003c\/li\u003e\n  \u003cli\u003eSpecifically designed to fit the \u003cstrong\u003eKoso 170cc Big Bore kit\u003c\/strong\u003e\n\u003c\/li\u003e\n  \u003cli\u003eOptimized combustion chamber for increased torque and throttle response\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eImportant Notes\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eLegal:\u003c\/strong\u003e Not legal for use in California on pollution-controlled vehicles; race use only in California — waiver available.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eInstallation:\u003c\/strong\u003e Requires the use of an iridium spark plug. Professional installation recommended to ensure correct tuning and fitment with the Koso 170cc kit.\u003c\/p\u003e\n\n\u003cp\u003eIdeal for riders seeking a reliable performance upgrade for track or off-road competition, the KOSO 4 Valve Cylinder Head pairs seamlessly with Koso big bore components to unlock the engine’s potential.\u003c\/p\u003e","brand":"KOSO","offers":[{"title":"Default Title","offer_id":52243567706430,"sku":"27-5822-51s","price":819.55,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0801\/0373\/5614\/files\/cceb-5fa1d109a7738.jpg?v=1758387221","url":"https:\/\/thed-zone.myshopify.com\/products\/4-valve-cylinder-head","provider":"thed.zone","version":"1.0","type":"link"}