Jims Machine JM-2404 Adjustable Pushrods for Panhead 53-65Use on Big Twin 1953 65. Pushrods have 32 threads per inch, with a 7 16# ball rocker end and a 1 4# ball tappet end. Made from aerospace quality aluminum tubing and heat treated steel ends. These lightweight pushrods provide maximum durability and long life. No disassembly of the top end or removal of the cam is required. JIMS# pushrods replace the stock steel rods and still retain the stock hydraulic unit.