GY6 49cc 50cc 126mm Gearbox Output Final Drive Shaft for 139QMB 139QMA Rear Drum Brake 4-Stroke Scooter Moped ATV Go-Kart Parts

Engineered for 139QMB/139QMA 4-stroke engines with drum brake systems. Precision-machined gear interface ensures smooth power transfer with minimal energy loss. Forged alloy steel with special heat treatment provides exceptional torsional strength. Case-hardened surface enhances wear resistance for demanding operating conditions. Balanced shaft design reduces high-speed vibration. Improved spline tooth profile guarantees secure hub engagement for responsive acceleration. Direct replacement for worn components during transmission overhaul. Effectively addresses gear slippage and abnormal noise issues. Maintains exact factory dimensions for bearing and mounting alignment. Includes step-by-step guide for straightforward installation by professionals or DIYers.

Manufacturer: ‎LMchUY Brand: ‎LMchUY Model: ‎LMchUY18 Item Weight: ‎1.76 ounces Package Dimensions: ‎0.39 x 0.39 x 0.39 inches Item model number: ‎LMchUY18 Manufacturer Part Number: ‎LMchUY18 ASIN: B0F6XZQJ71 Date First Available: April 30, 2025