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GOOFIT

Kick Start Idle Shaft Gear (7 Spline) for GY6 49cc 50cc 80cc QMB139 Scooter ATV

Kick Start Idle Shaft Gear (7 Spline) for GY6 49cc 50cc 80cc QMB139 Scooter ATV

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Regular price $8.99
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Product Overview

Eliminate starting friction and restore your engine's ignition efficiency with the GOOFIT High-Strength 7-Tooth Idle Shaft Gear. Engineered specifically for 4-stroke GY6 49cc to 100cc (QMB139) Chinese-made engines, this gear is the heart of a smooth kick-start system.

Standard gears often fail due to the intense mechanical shock of kick-starting. Our gear features heat-treated steel to maximize surface hardness and abrasion resistance. Whether you are maintaining a TaoTao, Baja, or Roketa, this precision component reduces resistance during the start-up stroke, ensuring your scooter or ATV fires up reliably every time.

Product Compatibility

Direct replacement for 4-stroke QMB139 series engines. Please verify your spline count (7 teeth) before ordering.

Engine Type Compatibility Popular Brands
GY6 4-Stroke 49cc, 50cc, 80cc, 100cc TaoTao, Baja, Roketa
Engine Code QMB139 / P139QMB Ice Bear, Peace Sports, Wolf
Vehicle Types Scooters, Mopeds, ATVs Various Chinese 4-stroke Imports

Specifications

Precision measurements for guaranteed fitment.

Feature Detail
Spline Count 7 Teeth (7 Spline)
Gear Diameter 26mm (1.02")
Material Heat-Treated Hardened Steel
Process Hardened Surface for Anti-Abrasion
Package Includes 1x Kick Start Idle Shaft Gear

Key Features

  • Optimized 7-Tooth Design: Specifically manufactured for engines requiring the 7-spline configuration. The precise tooth geometry ensures a tight bite with the kick start spindle, preventing slippage and energy loss.
  • Heat-Treated for Longevity: The high-grade steel undergoes a rigorous heat-treatment process. This significantly increases hardness and wear resistance, allowing the gear to withstand thousands of start cycles without deforming.
  • Reduced Starting Resistance: By optimizing the gear's rotational balance and surface finish, this part improves starting efficiency, making the kick-start motion feel lighter and more responsive.
  • Strict Quality Control: Every component is subjected to professional performance testing. We ensure that the gear meets optimum standards for stability and impact resistance, reducing the need for frequent maintenance.
  • Universal Fit for QMB139: A perfect "drop-in" solution for most Chinese-made 4-stroke scooters and ATVs. It directly replaces damaged factory gears to restore original vehicle performance.
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Fitment FAQ

Will this part fit my specific model and year?

This replacement part is intended for Direct replacement for 4-stroke QMB139 series engines. Please verify your spline count (7 teeth) before ordering.; Engine Type; Compatibility; Popular Brands; GY6 4-Stroke; 49cc, 50cc, 80cc, 100cc; TaoTao, Baja, Roketa. Key physical/spec details from the product data include Direct replacement for 4-stroke QMB139 series engines. Please verify your spline count (7 teeth) before ordering., 7 Teeth (7 Spline), Gear Diameter: 26mm (1.02"). Use the compatibility table and product photos together before ordering.

Do I need to match the OEM part number?

Yes. If your original part has a stamped OEM or manufacturer number, match that number first before ordering. For this replacement part, also compare the OEM number, dimensions, connector or mounting style, engine/model year, and product photos. This is especially important for GY6/Baja/Roketa GY6/QMB139 models because similar model names can use different parts by year or trim.

What models or situations does this part not fit?

Do not order this replacement part for machines outside the listed compatibility, or for units with different OEM numbers, dimensions, mounting points, connectors, or year-specific configurations. Do not rely only on the model name or engine size.

What should I check before ordering?

Before ordering, compare your original part with the photos and check the OEM number, dimensions, connector or mounting style, engine/model year, and product photos. Recheck listed specs such as Direct replacement for 4-stroke QMB139 series engines. Please verify your spline count (7 teeth) before ordering., 7 Teeth (7 Spline), Gear Diameter: 26mm (1.02"). If any connector, mounting point, size, or year detail is different, confirm fitment before installation.