Plot hole: Mr. Foyt spies on J.J. and Victor to find out more about the Cannonball, yet fails to recognize them when they stop to pick him up.
Continuity mistake: In the scene where the pickup truck jumps over the train, you can see the passenger's cowboy hat fall off on impact, but in the very next scene he is shown still wearing it.
Continuity mistake: Roger Moore is in the crowd at the finish line as Dom Deluise and Burt Reynolds are talking to each other. A few seconds later you see Roger Moore's car driving to the finish line.
Visible crew/equipment: When the Sheik arrives at the hotel he gets out of his car and is talking. On the ground is a clear shadow of the boom microphone.
Continuity mistake: A cop pulls up beside the two guys driving the GMC, and the driver yells to the cop that he has no brakes, so the cop moves along. The two guys laugh about it as next shot suddenly shows train tracks 1,000 feet ahead of them with a bunch of people working on a railcar, and a roadblock sign out front.
Visible crew/equipment: At the construction site, J.J. trades insults with Sammy Davis Jr. and Dean Martin. As Sammy says his line "A LOT of them!" you can see the boom mic and camera crew reflected in his glasses.
Other mistake: When the Japanese car passes the troopers sitting by the road, they're going 125 miles per hour by their speedometer. The trooper says that they're doing 125, but the radar readout says 20.