KB PISTONS 1984-1992 Harley-Davidson FXRS Low Glide FORGED ALLOY PISTONS KB921.S

KB forged pistons are made from 4032 forged alloy with an 11% silicon content, formed in a forging press and then fully machined. Due to the material and manufacturing process these pistons have superior crack resistance under detonation or pre-ignition. They are suited for Street or Race applications with power adders such as NOS or boost. All Twin Cam and Sportster application feature coated skirts. Replacement rings are special order, please call for pricing.