The snake-hunting old desert rat (Dean Jagger) mangles the name of the saguaro cactus as a tourist might do, pronouncing it "sag-where-ah." In reality, the "g" is silent and correct pronunciation is "se-war-oh"- - something a person who made his living off the desert, as he did, would certainly know.
Motorcycle chase by the Colorado River: Second motorcycle cop crashes through a wooden barrier while chasing Kowalski. The barrier has three yellow and black striped horizontal boards; the cop clearly breaks all three boards in the crash, but when the shot returns to the cop sitting in the dirt, the top board is intact.
At 21:49, after Super Soul receives the first radio report about Kowalski, the Challenger goes up a hill into shadow with a large mound of earth on the left side of the road, then the road curves right at the top of the hill. A few seconds later, after a cut showing Kowalski driving, the car is on the road down the hill before the shadow, ready to climb the same hill again.
When naked girl motorcycle rider is talking to Kowalski near passenger side of car, her arms are at her side and she is a step back from the car. In the next shot, she is leaning against the car with her arms on the roof.
When Kowalski is taunted by the driver in the Jaguar, they up end racing one another, side by side. As they approach the narrow bridge, the Jaguar blows a tire and is sent off the road. The car roles over an embankment and upside-down into a massive puddle of mud. When Kowalski runs back to see if the guy is all right, the guy emerges from the wreckage clean from head to toe (with the exception of his legs which are wet up to his knees), even though he landed upside-down in mud.
When the bulldozers drop the blades, the blades overlap by about a foot, there is no gap between them. The next shot, a frontal camera shot, shows a gap between the blades, and there's a gap between them in every shot after that.
After the first motorcycle cop crashes, Kowalski flashes back to a motorcycle race. Two riders are shown crashing, and then one whom is assumed to be Kowalski. The rider is wearing a white jacket with black sleeves and a full face helmet, but after he crashes, he is shown getting up wearing an open helmet with goggles and a dark greenish-blue jacket with stripes. Curiously, the numbers are all the same, 28.
When the Kowalski drops off the biker who helps him get through the roadblock you can clearly see that one headlight is shattered. However, in the next scene when he picks up the female hitchhiker at night, all four headlights are working perfectly.
Just two seconds before the seventeen minute mark, when Kowalski is being chased by the two motorcycle cops, fifteen to twenty production vehicles can be seen parked in the background. A vehicle blocking normal road traffic can be seen in the background as well.
Cisco, California is approximately due south from milepost 165 on I-80 and is approximately 30 miles directly west of the California/Nevada border. It is also firmly in the Sierra Nevada mountains. The Cisco in the movie is actually, Cisco, Utah.
When the older cop (Robert Donner) tells the young cop (Paul Koslo) that Super Soul is monitoring police radio, the young cop says that that is illegal, and the older cop agrees. In fact, the courts have ruled that it is not illegal to listen to police radio, but it is illegal to use the information you gain from it to evade or break the law. (So presumably Super Soul passing the information to Kowalski IS illegal.)
The 19-inch racks in Super Soul's radio station with large tape reels (in one scene seen fast moving) are not audio equipment. These tape drives were used in computer systems in the 1970s to store data on tape.
In the opening sequence, when the Challenger makes the bootleg turn in front of the bulldozers, you can see that the driver is apparently wearing a curly wig (to match Barry Newman's hair) over a helmet, making his head look ridiculously oversized.