Kb Pistons Hypereutectic Cast Piston 9.6:1 .005 - Harley Evolution 80ci
About Kb Pistons
KB Performance Pistons builds hypereutectic and forged pistons for American V-twin engines, and is a long-standing choice for big-bore and stock-replacement rebuilds where budget and durability both matter.
Unleash the full potential of your Evolution 80ci engine with KB Pistons Hypereutectic Cast Pistons. Engineered for riders who demand superior thermal performance and a quieter, more efficient power plant, these pistons are designed to elevate your ride.
Why riders pick this
- 16% silicon hypereutectic alloy reduces thermal expansion
- Tight piston-to-cylinder clearances for quiet operation
- Optimized ring seal improves power and efficiency
- Ideal for stock and mild compression ratios
- Designed for air-cooled Harley Evolution 80ci engines
These hypereutectic cast pistons feature a specialized 16% silicon content alloy, drastically reducing thermal expansion. This allows for tighter piston-to-cylinder wall clearances in your air-cooled V-twin, leading to improved ring seal and a noticeable reduction in engine noise.
Engineered for Durability and Performance
- Advanced 16% silicon hypereutectic alloy for superior thermal stability
- Designed for tight piston-to-cylinder clearances to minimize blowby
- Delivers optimal ring seal for consistent power delivery
- Reduces engine noise and wear in air-cooled big twins
Optimized for Your EVO Build
Whether you're refreshing a stock Evolution 80ci or building a mild custom, these pistons are an ideal choice. The 9.6:1 compression ratio is perfect for pump fuel applications, providing reliable power without demanding exotic fuels. Ensure your cylinders are bored to the .005 over specification for a perfect fit and long-lasting performance.
Specifications
- Brand: KB Pistons
- Manufacturer Part #: KB305.005
- UPC: 800745130068
- Compression Ratio: 9.6:1
- Engine: EVO 80ci
- Length: 9.5 in
- Width: 4.8 in
- Height: 4.6 in
- Weight: 2.75 lbs
- Country of Origin: Mexico
Common questions
What compression ratio do these pistons provide?
These KB Pistons are designed for a 9.6:1 compression ratio, suitable for stock and mild builds up to 10.5:1 on pump fuel.
Will these pistons fit my Evolution 80ci engine?
Yes, these pistons are specifically designed for air-cooled Evolution 80ci engines. Please confirm the .005 overbore requirement with your cylinder measurements.
Why choose hypereutectic pistons for an air-cooled engine?
The 16% silicon content in hypereutectic pistons provides excellent thermal stability and low expansion, allowing for tighter piston-to-cylinder clearances that reduce noise and wear in air-cooled applications.
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 | Kb Pistons |
| TYPE | Piston kits & Components |
| SKU | 824-01007 |
| WEIGHT | 2.75 lb |
| 9.6 | 1 Compression |
