Kick Start Idle Shaft Gear (8 Spline) for GY6 49cc 50cc QMB139 Scooter ATV

Product Overview

Restore smooth and reliable starting to your scooter with the GOOFIT Heavy-Duty Kick Start Idle Shaft Gear. Designed specifically for the 4-stroke GY6 49cc/50cc (QMB139) engine, this 8-spline gear is the essential replacement part for fixing common kick-start slipping and grinding issues.

When your kick starter feels loose or fails to engage the engine, a worn idle gear is often the culprit. Our gear is forged from high-quality CNC aluminum alloy, providing the strength and rust-proof durability needed to withstand the mechanical stress of repeated starting. It is a direct fit replacement built to strict quality standards, ensuring a quick and easy DIY installation.

Product Compatibility

Direct replacement for most Chinese 4-stroke GY6 50cc scooters, ATVs, and Quads.

Engine Type	Common Vehicle Applications	Fitment Notes
GY6 49cc / 50cc	TaoTao, Ice Bear, Wolf, Peace Sports, VIP	8 Spline Only
QMB139 (4-Stroke)	Roketa, SunL, Tank, Gator, Bintelli	10mm Shaft Fit
Vehicle Types	Scooters, ATVs, 4-Wheelers, Quads	Check Spline Count

Specifications

Please carefully verify your original gear dimensions before ordering.

Feature	Detail
Spline Count	8 Spline
Shaft Diameter	10mm (0.39")
Outer Diameters	20mm (0.78") & 33.5mm (1.31")
Material	Forged CNC Aluminum Alloy
Properties	Rust-Proof, High-Strength, Anti-Wear

Key Features

• Forged Strength: Unlike standard cast gears, our idle gear is forged with high-quality CNC aluminum alloy. This process ensures a denser, stronger material that resists tooth-chipping and spline-stripping.
• 8-Spline Precision Fit: Specifically designed with an 8-spline configuration to match the factory QMB139 kick start spindle. This ensures perfect engagement and prevents power loss during the kick-starting motion.
• Rust-Proof & Durable: The advanced alloy material is naturally corrosion-resistant, protecting the gear from moisture and road grime trapped inside the CVT cover, significantly prolonging service life.
• Direct OEM Replacement: Built to meet or exceed strict quality standards. It is designed to be a "drop-in" replacement for your old or damaged gear, requiring no modifications to your transmission assembly.
• Improved Starting Response: A fresh gear with sharp splines provides instant grip, reducing the effort needed to kick-start your engine and protecting other internal transmission components from unnecessary wear.