+.010in. Forged 89ci Stroker Pistons. Fits Evolution Big Twin 1984-1999 with S&S 4-5/8in. Stroker Flywheel - S&S Motorcycle Covers Equal parts shirt-jacket style and

Equal parts shirt-jacket style and functional gear

* Made of aircraft-grade Lucite in black opaque finish

Material: Ultra-durable vinyl

Certification: Certified to EN 17092-4:2020

+.010in. Forged 89ci Stroker Pistons. Fits Evolution Big Twin 1984-1999 with S&S 4-5/8in. Stroker Flywheel - S&S Motorcycle Covers Equal parts shirt-jacket style andThese forged 3 1 2" bore stroker pistons for 1984 '99 HD Evolution big twin engines are required for the S&S 89" 4 5 8" stroker flywheels. Pistons are designed to be used with stock cylinder heads or with S&S Performance Replacement heads # SS106 6064. Low silicon forged material and advanced S&S piston skirt design result in high strengh and low noise. 3 1 2" +. 010" bore. Tech Tips: * Follow Ring End Gap & Piston to Cylinder Clearances as per the