GOOFOUND 50CC GY6 Carburetor for 49cc-50cc Scooters — 139QMB/139QMA Fit, #78 Main Jet & Electric Choke

If your GY6-powered scooter struggles to start, idles poorly, or needs a reliable replacement part, this GOOFOUND 50CC carburetor is built to restore smooth operation. Designed for compatibility with 139QMB and 139QMA engines, the unit arrives with a #78 main jet, an electric 2-pin choke, and a full accessory kit so you can swap it in without hunting for extra components.

How does this carburetor improve starting and idling?

The GOOFOUND carburetor uses an upgraded #78 main jet and a calibrated air-fuel pathway to deliver a more consistent mixture at low RPMs. The included 2-pin electric choke helps cold starts by enriching the mixture until the engine warms up, which reduces starter strain and uneven idling.

• #78 main jet for optimized fuel flow
• Electric 2-pin choke for easier cold starts
• Tuned pilot circuit to stabilize idle
• Pre-installed components to minimize tuning needs

Will this fit my 49cc–50cc GY6 scooter or moped?

This carburetor is made to fit most Chinese-manufactured GY6 49cc and 50cc 4-stroke engines, including popular 139QMB and 139QMA platforms. Check the intake inner diameter and mounting pattern of your existing carburetor to confirm fitment before purchase.

• Intake inner diameter: 18 mm; outer diameter: 40 mm
• Compatible with GY6 139QMB and 139QMA engines
• Typical fit for many 49cc–50cc scooters and mopeds
• Verify physical measurements and plug type before installation

What comes in the package and what tools will I need?

The kit includes the carburetor, an intake manifold, a spark plug, a fuel filter, and two gaskets so you have the core parts needed for replacement. Basic hand tools and a few minutes of preparation—like labeling hoses and photographing the original setup—will make installation straightforward.

• Included: 1 carburetor, 1 intake manifold, 1 spark plug, 1 fuel filter, 2 gaskets
• Main jet size provided: #78
• Recommended: socket set, screwdrivers, pliers, and hose clamps
• Tip: photograph and label vacuum/fuel lines before removal

How simple is installation and are there tuning tips?

Installation is designed to be plug-and-play for many GY6-based scooters, with a direct-fit intake and electric choke connector. After mounting, verify choke operation, check for vacuum leaks at the manifold and gaskets, and make minor throttle or idle adjustments as needed for optimal performance.

• Plug-and-play electric choke connector for quick hookup
• Use supplied gaskets to prevent intake leaks
• Inspect and tighten hose clamps after test run
• Adjust idle and air/fuel mixture per manufacturer guidance

Who this is for: Riders, mechanics, and DIY scooter owners who need a dependable replacement carburetor for 49cc–50cc GY6 scooters and mopeds will appreciate this complete GOOFOUND kit. It’s suited for anyone replacing a worn or damaged carburetor, upgrading a poorly performing unit, or assembling a simple tune-up using parts that match common GY6 specifications. Confirm engine compatibility and measurements before ordering, and contact GOOFOUND support if you need help identifying the correct model.