S&S +.010in. Forged 89ci Stroker Pistons. Fits Evolution Big Twin 1984-1999 with S&S 4-5/8in. Stroker Flywheel

Description

These forged 3-1/2in. bore stroker pistons for 1984-’99 HD® Evolution® big twin engines are required for the S&S 89in. 4-5/8in. 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. 3-1/2in. +.010in. bore.

Tech Tips:-

* Follow Ring End Gap & Piston to Cylinder Clearances as per the supplied ManufacturersInstructions.

* Pull the engine down first & measure the existing bore to determine if oversize pistons are required PRIOR to purchase, we do not take back piston kits. The onus is on the assembling technician to validate the cylinders & required pistons.