I just received my new 551 Griptilian. It seems just a little stiff on opening and closing. How do I lube it or is there something else I need to do to make it smoother. It opens and closes fine with a little pressure. I would be fine with it on most knives but I expect more from a benchmade. I have a mini Griptilian that opens and closes silky smooth, thats what I want. How do I get there with the 551?