Piston Kit

Restore like-new compression and crisp throttle response with this PROX Piston Kit—manufactured in Japan as an OEM-replacement solution for 2-stroke 85cc engines. It’s cast from a high-silicon-content aluminum alloy and CNC-machined to extremely close tolerances, helping you achieve reliable fitment and consistent performance after a top-end refresh.

If your bike is showing signs of wear (loss of compression, harder starting, reduced power), a quality piston kit is one of the most effective ways to bring the engine back to life and protect the cylinder from further damage.

Key features:

• ✅ OEM-replacement quality – designed to meet or exceed OEM specifications
• ✅ Japan-made, precision-machined – high-silicon cast aluminum, CNC finished to tight tolerances
• ✅ Complete kit – includes piston, ring kit, wrist pin and circlips

Benefits of use:

• 🔹 Reliable rebuild results with correct fit and dependable sealing
• 🔹 Improved starting and power by restoring compression on worn top ends
• 🔹 Convenient all-in-one kit—no need to source small parts separately

Technical specifications (if needed):

• 📌 Displacement: 85 cc
• 📌 Engine type: 2-Stroke
• 📌 Bore size: 48.50 mm
• 📌 Piston size: 48.46 mm
• 📌 Type: Standard Size B
• 📌 Compression ratio: Standard
• 📌 Skirt coating: Non-coated
• 📌 Brand: PROX (Vendor part number: 01.4124.B)

Why choose this product?

• ⭐ Built to OEM standards for dependable fit and long-term durability
• ⭐ Precision manufacturing helps deliver consistent performance after installation
• ⭐ Complete kit contents make top-end service faster and simpler