Kb Pistons Hypereutectic Cast Piston - Pistons EVO 80ci 9.6:1 .010 — Harley-Davidson (1984-1999)

KB Pistons Hypereutectic cast piston for EVO 80ci engines at 9.6:1 compression ratio, sized .010 over. Cast from a 16% silicon alloy that resists thermal expansion and delivers tight piston-to-cylinder clearances, reducing blowby and engine noise while minimizing wear in air-cooled applications.

Features

• 16% silicon hypereutectic alloy
• Low thermal expansion rate
• Tight piston-to-cylinder clearance
• Optimal for stock and mild compression ratios
• Reduced engine noise
• Designed for air-cooled engines

Specifications

• Brand: KB Pistons
• Manufacturer Part #: KB305.010
• UPC: 800745130075
• Engine: EVO 80ci
• Compression Ratio: 9.6:1
• Oversized: .010 in
• Length: 9.6 in
• Width: 4.8 in
• Height: 4.6 in
• Weight: 2.8 lbs
• Country of Origin: Mexico

Fitment

Fits air-cooled EVO 80ci Harley engines. Ideal for stock and mild compression builds up to 10.5:1 running on pump fuel.

Frequently Asked Questions

What compression ratio is this piston designed for?

9.6:1, suitable for stock or mild builds up to 10.5:1 compression on pump fuel.

Why hypereutectic instead of forged?

The 16% silicon content provides excellent thermal barrier properties and low expansion, making it ideal for air-cooled engines. Hypereutectics work best at stock to mild compression ratios.

Is this .010 over or stock size?

.010 inch oversized. You will need to bore your cylinders .010 over to fit these pistons.

Will these reduce engine noise?

Yes. The tight piston-to-cylinder clearance from low thermal expansion helps minimize piston slap and reduces overall engine noise.