Nicely done. I just downloaded and played the game several times. I like the groovy 8-bit track and graphics. The bright colors and sprites are well done!
It would be cool if the cop car was closer behind you to increase the tension, and if the potholes only slowed you down temporary. Right now, once you hit a pot hole, it slows you down so much that there isn't much reason to keep going (you might as well restart). If the slowdown was temporary, it would feel like you could have the ability to recover.
Anyway, nice work! I enjoyed playing your game!