First or third one are great. The black one (IMO) is atrocious. I guess it wouldn't be so bad if it weren't for the orange from the a post on up. It looks so lazy and half-assed. Same with the fourth one with the random bar door to door across the front.
Of the 4 choices as is I would have to go with the 1st option. The 2nd would work with a white version for day races and the black for night races with white numbers on both. The 3rd would be better if the barely visible stripes on the side actually matched the colors of the owl instead of the silver. The 4th is just stupidly random like it was done by a 10 year old.