I do like the first one. The second one has promise but it seems to me that the tumbler on the cement mixer is blown out, but I think this could be fixed in post.
#1 is interesting because it contrasts the seeming calm and indifference of the spectator with what viewers know as the noise and activity of a moto race.
Composition and conversion are good. There might have been other ways to shoot this that might even improve the impression - waiting until the cycles were more in the frame and/or shooting at lower shutter speed to motion blur the cycles.
#2,3 & 4 are much less interesting because they make no points and are just decently made photos of essentially uninteresting scenes.