Wiseco 1340 EVO Big Twin 10:1 Compression Piston Kit - Harley Evolution
About Wiseco
Wiseco has forged pistons in Mentor, Ohio since 1941, supplying everything from factory race teams to big-bore street builds. Forged construction is what lets a V-twin survive higher compression and more cylinder pressure than the stock cast piston was designed for.
Upgrade your 1340cc Harley EVO Big Twin engine with this Wiseco Piston Kit, engineered for a potent 10:1 compression ratio. These forged pistons are built from high-silicon, low-expansion aluminum, ensuring superior strength and durability under demanding conditions. Experience a noticeable improvement in engine response and power delivery.
Why riders pick this
- Achieves a powerful 10:1 compression ratio
- Forged high-silicon aluminum for extreme strength
- Precision diamond-turned finish for exact fit
- Compatible with all common cylinder bore types
- Reduces weight and improves heat transfer
When building a high-performance 1340 EVO, every component matters. Wiseco's forged piston kits are a cornerstone of reliable power, offering significant advantages over stock cast pistons in terms of strength, weight reduction, and heat management. This kit provides the robust foundation needed for an aggressive engine build.
Robust Design for Power Builds
- Forged high-silicon, low-expansion aluminum construction for extreme durability
- Diamond-turned finish with no size variation ensures a perfect fit and seal
- Compatible with diverse cylinder bores, including cast iron, chrome, nikasil, and boron composite
- State-of-the-art computerized manufacturing for consistent quality and performance
Unlocking EVO Performance
The 10:1 compression ratio is a proven way to extract more power from your 1340 EVO Big Twin. To maximize the benefits of this piston kit, consider a comprehensive approach that includes a performance camshaft, a free-flowing exhaust, and a custom dyno tune. This synergy of parts will ensure your engine runs efficiently and delivers peak performance.
Specifications
- Brand: Wiseco
- Manufacturer Part #: K1665
- Engine: 1340cc EVO Big Twin
- Compression Ratio: 10:1
- Weight: 2.7964 lbs
Common questions
What fuel type is recommended with a 10:1 compression ratio?
A 10:1 compression ratio typically requires premium octane gasoline to prevent pre-ignition and ensure optimal engine health. Always confirm with your engine builder or tuner.
Are these pistons designed to be a direct drop-in replacement?
While designed for the 1340cc EVO Big Twin, proper piston installation often requires checking cylinder bore clearances and potentially honing or boring the cylinders. Professional installation is recommended.
Can I use this kit if my cylinders have been re-sleeved?
Yes, Wiseco offers oversized options to accommodate cylinders that have been re-sleeved or bored to a larger diameter. Please confirm your specific cylinder dimensions before ordering.
Ordering from Vtwinbikers
- Brand new, sourced through authorized US distribution — never used, never grey-market.
- Not sure it fits? Use Shop by Bike to filter by your year and model, or email us and we will confirm before you order.
- Harley-Davidson and Indian Motorcycle is all we do, so you are talking to people who ride what you ride.
| BRAND | Wiseco |
| TYPE | Piston kits & Components |
| SKU | K1665 |
| WEIGHT | 2.8 lb |
| 10 | 1 Compression |
