GY6 171cc / 172cc Builder Engine Kit (LONG CASE)

The Details ⚙️

Want to build a high-compression 171cc (172cc) GY6 engine from a fresh platform? This builder kit gives you nearly everything needed to assemble a serious performance motor — without piecing it together yourself.

This is a 12:1 compression setup built around proven components, making it ideal for high-performance street builds or aggressive setups.

Now customizable with two key options:

• 🧱 Piston Type: Cast or Forged
• 🔥 Fuel System: 28mm PWK Carb or ProBld EFI

🚀 Learn more about EFI:

👉 ProBld Plug & Play EFI System

A complete foundation for a serious GY6 build — built right from the start 🔧🔥

Choosing Your Setup 🤔

Piston Options:

• 🧱 Cast: Lower cost, solid for most builds and daily riding
• 💪 Forged: Stronger under heat and load — best for aggressive riding and high-performance setups

Fuel System Options:

• 🔥 Carb: Simple and proven, but requires tuning
• ⚡ EFI: Plug-and-play fueling, smoother running, and no rejetting

Cast = budget-friendly. Forged = max durability. Carb = hands-on. EFI = set it and forget it 💨

What's Included 📦

• 🧠 61mm 171cc Cylinder & Piston Kit (cast or forged)
• 🫁 Performance cylinder head (big port)
• ⚙️ Performance camshaft
• 🧩 Timing chain tensioner & guides
• 🔩 Complete engine hardware + top-end kit
• 🧠 Valve cover & rocker assembly
• 🧊 Cooling shrouds
• ⚡ High torque starter
• 🛢️ Engine oil
• ⚡ Spark plug

Depending on configuration:

• 🔥 PWK 28mm carb kit
• ⚡ ProBld EFI system

Final components vary based on your selected options.

Important Things to Note 🚨

• DO NOT remove the piston from the cylinder. Rings are pre-installed and measured — removing can damage them.
• This is a pre-configured builder kit — final assembly and tuning required.
• Engine comes with long axle and stock gearing.
• Additional upgrades (CVT, axle, gearing) may be required depending on your build.
• No warranty on performance engine components.

Optional upgrades:

👉 Short Axle Kit
👉 Gear Up Kit
👉 Performance CVT Kit
👉 Reveno Ultimate CVT Kit

Not sure how to spec your build? Message us — we’ll help you plan it 👍