The advantage Zash has on the metal wheel controlled by the maniac is being able to do sharp turns. The disadvantages are it being much faster and much more willing to cause copious amounts of property damage by just swerving into a wall.
Also by throwing small localised grenades at Zash, which he can shoot out of the air but which still slow him down. The bomber's destination is obvious, and unfortunately for Zash, the bomber gains and gains and gains on him and just... loses him. Even though his destination is obvious, he is still much faster.