Replacement rods (note the round holes for oiling the wrist pin) Originals have slots. Just need to get the locks on (S&S says, "don't use them") Just more stuff to fall off and go through the motor. If the pin and nut is installed correctly, and torqued correctly - it shouldn't be a problem. Make sure the screw is clean and use lock-tite on that too. Drag racers weld the nut !