The game would be a race from A to B through several checkpoints. I think there are two approaches for the concept of time.
The game starts with some time and player has to make it to the finish before it runs out. Extra time is granted at the checkpoints. Time left at the finish is counted as a score.
The time at the start is 00:00 and the stopwatch is halted at the finish. Player still has to go through checkpoints.
Opinions about these? I think the option 1 is more common but I find it frustrating for beginners.