• 39mm Piston Kit Assembly for 50cc 4-Stroke Horizontal Engine - goofitmoto
  • 39mm Piston Kit Assembly for 50cc 4-Stroke Horizontal Engine - goofitmoto
  • 39mm Piston Kit Assembly for 50cc 4-Stroke Horizontal Engine - goofitmoto
  • 39mm Piston Kit Assembly for 50cc 4-Stroke Horizontal Engine - goofitmoto
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GOOFIT

39mm Piston Kit Assembly for 50cc 4-Stroke Horizontal Engine

39mm Piston Kit Assembly for 50cc 4-Stroke Horizontal Engine

$9.99
$9.99
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Product Overview

This premium 39mm Piston Kit is a complete top-end rebuild solution designed for 4-stroke 50cc horizontal engines. Engineered for precision and durability, it restores optimal compression and engine performance to your ATV, Dirt Bike, or Go Kart.

Product Compatibility

This kit is compatible with most Chinese-manufactured 4-stroke horizontal engines (typically found in "Monkey Bike" style layouts).

Vehicle Type Common Compatible Brands/Models
ATV / Quad TaoTao, Buyang, Coolsport, Kazuma, Sunl, Roketa (50cc Models)
Dirt Bike Honda CRF50/XR50 Replicas, SSR, Coolster, Piranha
Go Kart 50cc 4-Stroke Kids Go Karts
Engine Style 50cc Horizontal Engine (Kick Start or Electric Start)

Specifications

Component Measurement
Piston Diameter 39mm ($1.53"$)
Wrist Pin Diameter 13mm ($0.51"$)
Wrist Pin Length 31mm ($1.22"$)
Engine Type 4-Stroke Horizontal
Material High-Grade Alloy & Spring Steel Rings

Key Features

  • Precision Engineering: 39mm bore size ensures a perfect seal and restored factory compression levels.
  • Durable Construction: Piston rings are crafted from special spring steel for superior heat resistance and longevity.
  • Complete Rebuild Kit: Includes the piston, wrist pin, circlips, and a full ring set for a hassle-free installation.
  • Universal Fitment: Designed to fit a wide range of Chinese 50cc ATVs, Dirt Bikes, and Pit Bikes with horizontal layouts.
  • Reliable Performance: Manufactured to meet or exceed OEM standards for smooth engine operation and reduced vibration.
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Fitment FAQ

Will this part fit my specific model and year?

This cylinder piston kit is intended for This kit is compatible with most Chinese-manufactured 4-stroke horizontal engines (typically found in "Monkey Bike" style layouts).; Vehicle Type; Common Compatible Brands/Models; ATV / Quad; TaoTao, Buyang, Coolsport, Kazuma, Sunl, Roketa (50cc Models); Dirt Bike; Honda CRF50/XR50 Replicas, SSR, Coolster, Piranha. Key physical/spec details from the product data include Piston Diameter: 39mm ( $1.53"$ ), Wrist Pin Diameter: 13mm ( $0.51"$ ), Wrist Pin Length: 31mm ( $1.22"$ ). 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 cylinder piston kit, also compare the bore diameter, piston-pin size, gasket pattern, stud spacing, engine code, stroke type, and cylinder height. This is especially important for Honda/Roketa/TaoTao CRF50/XR50 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 cylinder piston kit for machines outside the listed compatibility, or for units with different bore sizes, piston-pin diameters, stroke lengths, stud spacing, or gasket patterns. 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 bore diameter, piston-pin size, gasket pattern, stud spacing, engine code, stroke type, and cylinder height. Recheck listed specs such as Piston Diameter: 39mm ( $1.53"$ ), Wrist Pin Diameter: 13mm ( $0.51"$ ), Wrist Pin Length: 31mm ( $1.22"$ ). If any connector, mounting point, size, or year detail is different, confirm fitment before installation.