These Keith Black dome top pistons are precision-engineered from forged 4032 alloy containing 11% silicon, fully machined after pressing to deliver exceptional strength and crack resistance in high-compression performance applications. Designed for Harley-Davidson Big Twin engines from 1984 through 1999, they provide a 10.5:1 compression ratio with standard 80cc combustion chambers.

Supplied as a complete matched kit, this set includes two pistons, rings, wrist pins, and clips ready for installation. They are sized for an 89.4 mm bore with a 108 mm stroke and require an additional 0.03 mm piston-to-wall clearance for optimal engine operation.

Key Features

Highlights

• Engineered from forged 4032 alloy with 11% silicon for maximum durability
• Provides 10.5:1 compression ratio with 80cc combustion chambers
• Designed specifically for Harley-Davidson Big Twin 1984-1999 models
• Includes complete assembly: pistons, rings, wrist pins, and clips

Materials & care

Constructed from forged 4032 aluminum alloy with 11% silicon content for enhanced strength and thermal stability. Follow all manufacturer instructions for setting ring end gaps and cylinder wall clearances during assembly.

Compatibility

Compatible with Harley-Davidson Big Twin Evolution models manufactured from 1984 to 1999.

What's included

• 2 x Keith Black Dome Top Pistons
• 1 x Piston Ring Set
• 2 x Wrist Pins
• 1 x Set of Retaining Clips

Downloads

• Download Product information ( PDF)