{"product_id":"mitas-4-00-4-50-12-inner-tube-136-138","title":"Mitas 12\" Heavy Duty Bent Valve Inner Tube","description":"\u003cp\u003eKeep your 12-inch wheels rolling with confidence using the \u003cstrong\u003eMitas 4.00\/4.50-12 Inner Tube\u003c\/strong\u003e. Molded from high-density butyl rubber and engineered in Europe to rigorous performance standards, this heavy-duty tube resists seam splits, pinch flats, and thermal breakdown — delivering exceptional pressure retention under prolonged loads. An ideal replacement for wide 12-inch fat-tire scooters, mini-motos, and sidecars.\u003c\/p\u003e\u003ch3\u003eKey Features\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePremium Butyl Rubber:\u003c\/strong\u003e Uniform wall thickness and high elasticity reduce natural air migration and resist ozone degradation over time.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e90° Bent Metal Valve Stem:\u003c\/strong\u003e Pre-angled JS87\/DIN7777-style metal valve provides easy inflation access on tight 12-inch wheel hubs and split rims.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eReinforced Valve Base:\u003c\/strong\u003e Extra-thick vulcanized rubber pad absorbs rotational stress and prevents pull-shear flats at the stem.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThermal Stability:\u003c\/strong\u003e Withstands high internal rim temperatures generated during prolonged braking on smaller wheel platforms.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eRim Diameter:\u003c\/strong\u003e 12 inch\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSupported Tire Widths:\u003c\/strong\u003e 4.00\" to 4.50\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eValve Stem Type:\u003c\/strong\u003e 90° Bent Metal (JS87 \/ DIN7777)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e High-density butyl rubber\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSKU:\u003c\/strong\u003e 136-138\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eSize \u0026amp; Fitment Guide\u003c\/h3\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth style=\"text-align: left;\"\u003eImperial Size\u003c\/th\u003e\n\u003cth style=\"text-align: left;\"\u003eMetric Equivalents\u003c\/th\u003e\n\u003cth style=\"text-align: left;\"\u003eApplication\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e4.00-12 \/ 4.00x12\u003c\/td\u003e\n\u003ctd\u003e110\/90-12, 120\/70-12\u003c\/td\u003e\n\u003ctd\u003eStandard 12\" scooter front\/rear rims\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e4.25-12 \/ 4.25x12\u003c\/td\u003e\n\u003ctd\u003e120\/80-12, 130\/60-12\u003c\/td\u003e\n\u003ctd\u003eMid-profile urban commuters\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e4.50-12 \/ 4.50x12\u003c\/td\u003e\n\u003ctd\u003e130\/70-12, 130\/80-12, 140\/70-12\u003c\/td\u003e\n\u003ctd\u003eFat-tire variants and custom mini-bike setups\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch3\u003eInstallation Tips\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eAlways inspect the inside of your tire carcass for sharp debris, wire remnants, or burrs before inserting the new tube.\u003c\/li\u003e\n\u003cli\u003eDust the inside of the tire casing with talcum powder before sliding the tube in — this prevents rubber-to-fabric sticking and reduces the risk of pinch flats.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eAbout Mitas\u003c\/h3\u003e\u003cp\u003eMitas is a leading European tire manufacturer with decades of experience producing high-quality tires and tubes for motorcycles, scooters, and specialty vehicles. Their products are engineered to meet strict European performance and safety standards, making them a trusted choice for riders worldwide.\u003c\/p\u003e\u003cp\u003e\u003ca href=\"https:\/\/www.p65warnings.ca.gov\" target=\"_blank\" rel=\"noopener noreferrer\"\u003eCalifornia Prop 65 Warning: www.p65warnings.ca.gov\u003c\/a\u003e\u003c\/p\u003e","brand":"Mitas Tire","offers":[{"title":"Default Title","offer_id":49985980891416,"sku":"136-138","price":14.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0782\/1728\/1816\/files\/824293.jpg?v=1744827243","url":"https:\/\/www.scooterworks.com\/products\/mitas-4-00-4-50-12-inner-tube-136-138","provider":"Scooterworks USA, LLC","version":"1.0","type":"link"}