Why is expensive Mallory weight always added to a crankshaft counterweight? Why couldn't the underside of a piston or the bottom of a rod cap be lightened instead? The trick is to keep it as light as possible, isn't it? Why keep adding weight? I see this on tires in the dealership. People that have had their tires balanced several times in their life. Some come in with weights all over the inside of the rim. We all know that this is laziness on the part of the tech balancing the tires. Can the same be said for crank balancing?