You-All 18mm CVK PD18J Carburetor w/ Accelerator Pump

You-All 18mm CVK Carburetor - OEM PD18J Replacement

Eliminate hesitation and restore consistent power to your 50cc scooter with the You-All 18mm CVK Carburetor (PD18J). As our #1 selling carburetor, this unit is engineered to outperform standard OEM replacements by combining a larger venturi with a mechanical accelerator pump. Whether you are daily commuting on a Chicago Scooter Co. model or tuning a Honda Ruckus, this carburetor provides the precise fuel atomization needed for crisp throttle response and a rock-solid idle.

Performance & Reliability Features

• Mechanical Accelerator Pump: Features a dedicated fuel-squirt circuit that eliminates "bogging" and hesitation during rapid throttle transitions.
• High-Flow Venturi: A larger-than-stock venturi increases flow and fuel atomization.
• Black-Top CVK Dome:  The black-top CVK dome and improved idle circuit deliver superior engine idle to prevent unstable idle surging and stalling found on many OEM 50cc carburetors.
• Precision Jetting: Pre-installed with an #81 Main Jet and #33 Idle Jet, calibrated for immediate "bolt-on" performance on most 50cc-80cc engines.

Comprehensive Fitment Guide

This carburetor is the definitive replacement for 139QMB / GY6 50cc scooters and ATVs, including:

*Technical Tip: If your engine code includes "QM" or "FM", this part is compatible with your vehicle.

Technical Specifications

• Model: PD18J (CVK Type)
• Intake Bore: 18mm
• Air Filter Mount (OD): 40mm
• Main Jet: #81 / Idle Jet: #33

Mechanic's Note: After installation, ensure your Throttle Cable has a small amount of play to allow the accelerator pump to reset fully between twists!  Installation Tip: To prevent immediate clogging of the precision jets, we strongly recommend installing a new Fuel Filter and draining your old gas tank. 

SKU: 1300-1115
Vendor: You-All

This product is intended for off-road use only.

This product is not intended for use on public roads or land.

This product is not legal for use in California on pollution-controlled vehicles. Check local laws before installing.

*Performance upgrades are considered racing parts and are not covered by warranty. 

Brands: Amstar, Amigo, Ascend, Baotian, Bashan, Blade, Boom, Chicago Scooter Company, Dongfang, Roketa, Baotian, Bashan, BMS, Cool Sports, E Ton, Fly Wing, Eagle, Fly, Italica, Riya, Ice Bear, Jackel, Jet Moto, JCL, Taotao, Peace, JM Star, Jonway, Kazuma, Keeway, KMD, Kymco, Lance, Lifan, Linhai, Loncin, Longbo, Fuxin, Jiajue, Tao Tao, Tao Motors, Trailmaster, Maxtrade, Meitien, Motofino, Motorino, NST, Panterra, Panther, Qlink, Yiben, Red Streak, Redcat, Roketa, Schwinn, Strada, SYM, Tank, Terminator ,Tomberlin, TNG, United Motors, Vento, Vitacci, Wildfire, Wolf, X-Treme, X-Pro, Yongfu, ZNEN, Zhongneng , Zhilong, Geely, Wangye, ZH and more Manufactured by: Taizhou Zhongneng Motorcycle Co.; Jiangsu Zhongneng Motorcycle Co.; Jiangsu Meijunte Technology Co.; Taizhou Qianxin Vehicle Co.; Ningbo Dongfang Lingyun Vehicle Made Co.; Taizhou Zhilong Technology Co.; Zhejiang Jiajue Motorcycle Manufacturing Co.; Zhejiang Gelly Ming Industrial Co.; Taizhou City Senglong Motorcycle Manufacture Co.; Jiangsu Sacin Motorcycle Co.; Jiangsu Linhai Power Machinery Group Co.; Zheijiang TaoTao Vehicles Co.; Zhejiang Senling Motorcycle Co.; Sanmen County Yongfu Machine Co; Taizhou Jiaojiang Zhiwei Motorcycle Manufacture Co.; Huzhou Daixi Zhenhua Technology Trade Co.; Taizhou Zhongneng Motorcycle Co.; Zhejiang Riya Motorcycle Co.; Ningbo Longjia Motorcycle Co.; Taizhou Zhongneng Motorcycle Co.; and more