Also I take the little screw driver and press it flat and flush before tightening or the machine can possibly make more noise , yes it only slides a small amount mine does work though even if I don't use that feature much I have been running around 3.5 for a couple months I just adjusted it to max stroke the other day using a 14rl t tech, seemed to work pretty good 14rls can sometimes be a bitch anyways especially on the back of the arm