The game's main character is a racer who must travel on his motorbike from Los Angeles to New York while avoiding many cars who try to crash into the rider.
Screenshot of the arcade version.
Interestingly, every level has two parts:
The first part is an overhead game with the aforementioned gameplay. Cars overtaken during this part of the level cause the player's rank to increment by 1 per car. The current rank is shown in the bottom right hand corner of the game screen during each stage.
The second part has the player watching the biker from behind his back. The player must try not to crash into the opposite cars while a background relative to the city he's travelling to is shown (i.e.: if the player is reaching Las Vegas, then a few casinos can be seen in the background). Oncoming cars passed do not increase the player's rank.
There are five different stages that the player encounters on their way to the final destination (NY) before the game starts back at stage one as outlined below. These stages alternate from tarmac on stages one, three and five, to unsealed (dirt) roads on stages two and four. On the tarmac stages bonus fuel can be picked up by running over the gas can icon. There is also a "wheelie" section which when run over causes the rider's bike to do a wheelstand and gain bonus points. On the dirt road stages both fuel and points can be gained by running over the gas cans or the score amounts indicated on the playfield. On the dirt road stage there are several log bridges that cross water and a "jump" section on some bridges - riding over the jump icon results in a score bonus. On all stages there are puddles of water which, if ridden through, render the bike unable to steer for a short period of time and a tyre squealing sound is played briefly.
Crashing into cars, road edges, bushes/trees, rocks or missing a bridge and riding into the water on a dirt road stage results in the motorcycle stopping and losing an amount of fuel. Running out of fuel causes the game to end. Crashing can also result (especially in later levels) in being overtaken by cars which decreases the player's rank.
As the player reaches each city the rank achieved results in a bonus amount being added to the score and extra fuel added to the player's total. The higher the position achieved the more points and fuel awarded.
When the player reaches NY, a sign saying "Viva NY" will be shown while the Statue of Liberty waves its hand and the Star Spangled Banner is played. After this cut-scene, the game starts again with an increased difficulty and the player has a higher capacity motorcycle (with correspondingly faster top speed).
Source: Wikipedia, "Zippy Race", available under the CC-BY-SA License.