I'd avoid using lubricant, if at all possible. If you must use a lube, I'd suggest something designed specifically for the purpose, such as this.
Help! Will lubricant affect spkr.cables?
My H.Tech. Pro-9 bi-wire speaker cables are a very tight fit when trying to slide them up inside my B&W speaker stands. If I put some lubricant on the outside cover to help slide them through would it affect the sound of the wires? Any recommendations? I don't want to damage the casing in case of future resale.