I don't think any of them are excellent, they don't have any real subject, there isn't a theme... and they are slightly boring, there is nothing that makes me want to keep looking at it.
Out of them, the scooter is the best one, it has a feel to it.
I quite like the first picture out of them all for the fact that the central focus point isn't the individuals fishing, which I find with a lot of photographers, they make the central point extremely large in their photographs cutting out any surrounding.
The disappointing thing with the third picture is that, if it is what I think it is, I can see you (the photographer) in the reflection on the bike's body. If that isn't you then my mistake . Just with photographs I like the thought of a photo making me feel as if it were my eyes that are taking the picture rather than me looking at the photo itself, and when the reflection of the photographer is seeable, it ruins the mood so to speak.
I agree with everyone else, the last one is my favorite. Something about it, just looks good. Though I'm not sure if I would put it on my desktop. Who would want to look at a scooter all day? Try to find something, exciting
I hope that helped a tad. This is supposed to be constructive criticism.