{"product_id":"ncy-performance-camshaft-qmb139-1100-1250","title":"NCY Performance Camshaft 139QMB GY6 50cc","description":"\u003cp\u003eUnlock the hidden power potential of your 4-stroke scooter with the \u003cstrong\u003eNCY Performance Camshaft\u003c\/strong\u003e. Designed specifically for the GY6 139QMB engine platform, this high-lift cam profile increases valve duration and lift, allowing your engine to breathe deeper and rev higher. This is the recommended essential upgrade whenever you install a 72cc, 82cc, or 100cc big-bore cylinder kit to ensure your engine can fully utilize the increased displacement.\u003c\/p\u003e\u003cp\u003eBy optimizing the intake and exhaust timing, this camshaft shifts your power band upward, resulting in significantly improved acceleration and higher top-end performance. \u003c\/p\u003e\u003ch3\u003eProduct Features\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eOptimized Lobe Geometry:\u003c\/strong\u003e Increased lift and duration profiles significantly improve volumetric efficiency compared to restrictive OEM stock cams.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrecision-Machined Sprocket:\u003c\/strong\u003e Includes a factory-indexed 34-tooth timing sprocket for precise valve-to-piston synchronization.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHardened Steel Core:\u003c\/strong\u003e Constructed from high-strength, wear-resistant steel to withstand the sustained high-RPM heat and stress of modified performance builds.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePlug-and-Play Fitment:\u003c\/strong\u003e Designed for drop-in installation into stock 139QMB cylinder heads (no machining required).\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eIntake Lobe:\u003c\/strong\u003e 25.8mm x 21mm x 10.3mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExhaust Lobe:\u003c\/strong\u003e 25.5mm x 21mm x 10.2mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSprocket Teeth:\u003c\/strong\u003e 34\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBearings:\u003c\/strong\u003e 2 TPI #16002C3 (18x32x8mm)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSKU Reference:\u003c\/strong\u003e 1100-1250\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eComprehensive Engine Fitment Matrix\u003c\/h3\u003e\u003cp\u003eThis camshaft is a direct fit for 139QMB-based 50cc, 72cc, 82cc, and 100cc 4-stroke engines using the following factory designations:\u003c\/p\u003e\u003ctable style=\"width: 100%; border-collapse: collapse;\"\u003e\n\u003cthead\u003e\u003ctr style=\"background-color: #f8f8f8;\"\u003e\n\u003cth style=\"text-align: left; padding: 10px; border: 1px solid #ddd;\"\u003eEngine Series Code\u003c\/th\u003e\n\u003cth style=\"text-align: left; padding: 10px; border: 1px solid #ddd;\"\u003eCompatible 139QMB \/ GY6 50cc Variants\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\u003ctr\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #ddd;\"\u003e\u003cstrong\u003eCommon Codes\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #ddd;\"\u003e139QMA, 139QMB, 1P39QMB, 1P39QMA-2, YN139QMB, JJ139QMB, 139FMA-2, BD1P39QMB, BN139QMB, 147QMD\u003c\/td\u003e\n\u003c\/tr\u003e\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cdiv style=\"background-color: #fffaf0; padding: 15px; border-left: 5px solid #f0ad4e; margin: 20px 0;\"\u003e\n\u003cstrong\u003eTuning Mechanic's Advice \u0026amp; Safety Warning:\u003c\/strong\u003e When installing any high-performance camshaft alongside a big-bore kit, you \u003cstrong\u003emust\u003c\/strong\u003e manually verify valve-to-piston clearance by rotating the crankshaft by hand before attempting a startup. If you do not have adequate clearance, you risk catastrophic engine failure. Additionally, ensure your valve lash (clearance) is set to manufacturer performance specifications (typically 0.003\"–0.004\" for intake\/exhaust on modified engines) immediately upon installation.\u003c\/div\u003e\u003cp\u003e\u003cbr\u003e\u003ca href=\"https:\/\/www.p65warnings.ca.gov\" target=\"_blank\"\u003eCalifornia Prop 65 Warning\u003c\/a\u003e\u003c\/p\u003e\u003ch4 style=\"color: #983d3c;\"\u003eThis product is intended for off-road use only.\u003c\/h4\u003e\u003ch4 style=\"color: #983d3c;\"\u003eThis product is not intended for use on public roads or land.\u003c\/h4\u003e\u003ch4 style=\"color: #983d3c;\"\u003eThis product is not legal for use in California on pollution-controlled vehicles. Check local laws before installing.\u003c\/h4\u003e\u003cp\u003e\u003cstrong\u003e*Performance upgrades are considered racing parts and are not covered by warranty.\u003c\/strong\u003e\u003c\/p\u003e","brand":"NCY","offers":[{"title":"Default Title","offer_id":46756517937432,"sku":"1100-1250","price":72.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0782\/1728\/1816\/products\/1100-1250_1d7d662d-80fe-4749-b173-b03d5c034eb9.jpg?v=1695268876","url":"https:\/\/www.scooterworks.com\/products\/ncy-performance-camshaft-qmb139-1100-1250","provider":"Scooterworks USA, LLC","version":"1.0","type":"link"}