47mm Big Bore Cylinder Head with Valves & Gaskets for 4-Stroke GY6 80cc 139QMB 139QMA Engine (Non-EGR)

Product Overview

Restore your scooter's compression and power with the GOOFIT 47mm Big Bore Cylinder Head. This high-toughness replacement head is specifically designed for upgraded 80cc GY6 4-stroke engines (139QMB/139QMA). Featuring pre-installed 20mm intake and 30mm exhaust valves, this Non-EGR assembly is built to withstand high temperatures while reducing friction and air leakage, ensuring your engine runs at peak efficiency.

Product Compatibility

This is a 47mm Big Bore specific head. It is not compatible with standard 39mm (50cc) cylinders unless you have already upgraded to an 80cc bore.

Engine Type	Displacement	EGR Configuration
GY6 139QMB / 139QMA	80cc (47mm Bore)	Non-EGR Only
Compatible Vehicles	ATVs, Go Karts, Scooters	TaoTao, Wolf, Ice Bear, Bacci

Specifications

Attribute	Details
Cylinder Inner Diameter	47mm / 1.85"
Intake Valve Diameter	20mm / 0.78" (Bolt Spacing: 45mm)
Exhaust Valve Diameter	30mm / 1.18" (Bolt Spacing: 50mm)
Spark Plug Included	A7TC
System Type	Non-EGR (Standard)
Assembly Status	Completed with Valves & Springs

Key Features

• Optimized for 80cc Performance: Specifically engineered for 47mm big bore cylinders to provide the correct combustion chamber volume and air-flow for 80cc power outputs.
• Pre-Installed Valve Train: Comes fully assembled with high-quality intake and exhaust valves, saving you the time and hassle of using a valve spring compressor.
• Non-EGR Simplified Design: Perfect for standard performance setups that do not use Exhaust Gas Recirculation, reducing complexity and potential leak points.
• High-Toughness Construction: Cast from premium alloys that are rustproof and corrosion-resistant, designed to maintain structural integrity under high thermal stress.
• Improved Gas Sealing: Includes a full set of high-performance gaskets to ensure a reliable, airtight seal between the cylinder head and the engine block.