I used to have a Hex Wrench around, and would re-tighten the bar between sets when it became too much of a problem, then, the bar got grooves worn in it from the metal screw poking into it, so it built up sort of a fixed degree of rotation that way, then the darn screw wore flat, so I got a bigger screw and used that, which used a regular screw driver, then wore the end of the screw down too far.
So what I do now is buy a Tire repair kit, and cut up the rubber plugs to put a tiny section of it between the end of the screw, and the bar, the bar is moveable, but stays put, works like a charm.
