Piston Kit for Athena Big Bore Cylinder 4-Stroke

Upgrade or refresh your 4-stroke big-bore setup with a forged piston kit built for performance and reliability. This Athena piston kit is made specifically for Athena Big Bore cylinders, combining a precise 82.96 mm bore fit with a high 13.5:1 compression ratio to help bring back strong throttle response and consistent power. It’s a smart choice for riders doing a proper top-end rebuild who want a complete, ready-to-install kit.

Because the kit includes the key wear components (rings, pin and clips), it simplifies ordering and helps reduce downtime—so you can focus on getting the engine back together correctly and back on the track or trail.

Key features:

• ✅ Complete kit – includes rings, clips and wrist pin
• ✅ Forged construction – forged 2618 aluminum piston for durability under load
• ✅ Big-bore compatibility – engineered for Athena Big Bore 4-stroke cylinders

Benefits of use:

• 🔹 Reliable rebuild results thanks to a matched piston/ring package
• 🔹 Strong performance potential with 13.5:1 compression
• 🔹 Easier installation with included step-by-step instructions

Technical specifications:

• 📌 Product: Piston Kit (Kit)
• 📌 Engine type: 4-Stroke
• 📌 Displacement: 250 cc
• 📌 Bore size: 82.96 mm
• 📌 Compression ratio: 13.5:1
• 📌 Piston material: Forged 2618 Aluminum
• 📌 Piston size/type: Standard Size B / Type B
• 📌 Brand: ATHENA
• 📌 Vendor part number: S5F08300005B

Why choose this product?

• ⭐ Purpose-built for Athena Big Bore cylinder applications for correct fitment
• ⭐ Forged piston material for demanding riding and rebuild durability
• ⭐ Complete package with instructions to make your top-end job smoother