Had someone over the other day for a couple of quick games and noticed a bit of a drag on a couple of the shooter rods. I must say I hadn't really payed any attention but both compared to TWD they feel a bit juddery on the pull back and release. At one point, oiling it up slightly was mentioned and this made me think as I am sure any oil or grease near a pin is a no no. So all, how do you maintain your rods?