Kb Pistons Forged Alloy Piston - Pistons EVO 80ci 10.5:1 .005 — Harley-Davidson (1984-1999)

KB Pistons forged alloy pistons for Harley EVO 80ci engines with 10.5:1 compression ratio and .005 oversized bore. Made from 4032 forged alloy with 11% silicon content for superior crack resistance under detonation and pre-ignition, ideal for street or race builds running power adders like NOS or turbo boost.

Features

• 4032 forged alloy with 11% silicon content
• Superior crack resistance under detonation and pre-ignition
• Coated skirts on Twin Cam and Sportster applications
• Includes rings, wrist pins, and wrist pin locks
• Sold as a pair

Specifications

• Brand: KB Pistons
• Manufacturer Part #: KB921C.005
• UPC: 800745155368
• Bore Size: .005 oversized
• Compression Ratio: 10.5:1
• Engine: EVO 80ci
• Weight: 2.5 lbs per pair
• Country of Origin: Mexico

Fitment

Fits Harley EVO 80ci engines. Designed for street or race applications running power adders such as NOS or turbo boost.

Frequently Asked Questions

What's included with the piston pair?

Each pair includes all rings, wrist pins, and wrist pin locks ready for assembly. No additional internal hardware needed.

Can I use replacement rings later?

Yes — KB Pistons replacement rings are available but are special order. Contact the manufacturer for current availability.

Will these pistons work on a stock EVO or mild street build?

These 10.5:1 pistons are engineered for boosted and high-detonation applications. Standard street builds may want lower-compression options.

Do the wrist pins and locks need to be ordered separately?

No — wrist pins and locks are included with the piston pair. Note that each piston requires 2 wrist pin locks.

Are the skirts coated on all applications?

Coated skirts are included on Twin Cam and Sportster applications. Check with KB Pistons for other engine platform specifics.