This does not adjust fuel pressure, this adjusts fuel volume that is injected. Raising fuel injection pressure above normal will do little to nothing for performance if the injectors are operating properly.
So yeah i noticed that the retaining cap is flanged and recessed into a seat around the screw, which means the dang thing will turn all day long without coming off. What I did and what I would recommend, is a combination of a medium sized flat head screwdriver or a small cold steel chisel, and a pair of vice-grip or locking groove pliers to basically deform the flange of the cap enough to pry it off. You might scratch up the paint a bit, but the engine block is cast-iron so I wouldn't worry about hurting it.
This was my former employer Burke Mountain, a ski resort. In this video I was climbing the mid-lodge lower slope to test the adjustment. The poles are snowmaking guns, they line either side of the slope.
Tilt the bed up, take out the seats and storage bins. And on the front of the engine easily accessible is a screw that is covered with a retaining cap that has a painted on reference line to mark screw position. I gave this screw 4 half turns (I always work in half turns, just me). That was enough to get it from gutless to a little bit of black smoke at WOT. There is no way to get this protection cap off without destroying it. I didn't need to worry about warranty. YMMV.
@@shickenchits8123 counterclockwise for more fuel clockwise for less fuel, he turned it four half turns counterclockwise which would be two full turns counterclockwise
For a youtube video on how to actually find the screw to adjust the fuel pressure on the RTV-X900 check out this link - ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Mz6Rb9wBwf8.html