My body weight may not be much, but I use what I got.Prestretching Kevlar and Zyex. I don't think you can get much of a prestretch of Ash Kev using the door knob body weight pull. You need a tie off point and winch. If you cant't have that then just pull tension 3 times and accept what you get. Body weight prestretching Zyex is easy. Ash Kev not so much.