S&S Cycle 2007+ BT 4-1/8in DD Piston Set

S&S 4 1/8" Bore Forged Piston Kit For 1984-'16 Hot Set Up Kit. These pistons are machined to close tolerances. Early production pistons with no micrometer window make measurements difficult. Hone cylinders to nominal diameter +/- 0.0001" for correct clearance. Current production pistons have micrometer windows to allow accurate measurements. These can be installed by honing cylinder to nominal diameter +/- 0001" or by measuring piston and honing cylinder to achieve .002" - .0025" close clearance for street applications or .0032" - .0045" loose clearance for immediate competition use. Includes set of pistons, rings, wristpins, and clips.