To assure consistent valve train operation under all conditions, S&S^® adjustable pushrods are manufactured from rigid chromoly steel tubing. OEM pushrods may be cut to permit removal without rocker disassembly. These pushrods fit 1999-'16 HD^® big twin engines with stock, 4.937" cylinders. 1984-'99 style pushrods covers required. You will need to remove the tappets blocks so you don’t have to remove the rocker boxes