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39mm Cylinder Block for GY6 139QMB 49cc 50cc 4-Stroke Engine

39mm Cylinder Block for GY6 139QMB 49cc 50cc 4-Stroke Engine

Regular price $32.99
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Product Overview

Replacement 39mm cylinder block for compatible GY6 139QMB 49cc and 50cc 4-stroke engines used in scooters, mopeds, ATVs, and go-karts.

Designed for standard-size 39mm cylinder applications, this cylinder block is suitable for replacing a worn, scored, damaged, or otherwise unusable original cylinder when the engine dimensions match.

Constructed with an aluminum-alloy outer body and cooling-fin design for compatible air-cooled GY6 applications.

Product Compatibility

Engine Platform Engine Size Application
GY6 139QMB 49cc / 50cc Scooter
GY6 139QMB 49cc / 50cc Moped
GY6 139QMB 49cc / 50cc ATV / Quad
GY6 139QMB 49cc / 50cc Go Kart

Specifications

Specification Details
Product Type Cylinder Block
Engine Platform GY6 139QMB
Engine Type 4-Stroke
Engine Size 49cc / 50cc
Cylinder Bore Approx. 39 mm / 1.54 in
Cooling Type Air-Cooled
Outer Construction Aluminum Alloy
Applications Scooter / Moped / ATV / Go Kart
Replacement Type Aftermarket
Condition New

Key Features

  • 39mm Cylinder Bore: Designed for compatible standard-size GY6 139QMB 49cc / 50cc applications.
  • 139QMB Engine Fitment: Suitable for selected Chinese 4-stroke scooter and small-engine platforms.
  • Cooling-Fin Design: Provides surface area for heat dissipation in compatible air-cooled engines.
  • Replacement Cylinder Block: Suitable for top-end repairs involving a worn or damaged original cylinder.
  • Dimension-Based Fitment: Designed to be confirmed by bore size, engine code, sleeve dimensions, and mounting pattern.
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