Revealing mistake: In the day following the Rider's first ride, Cage shows up at the street that has been burned down the center. A person very close to the beginning of that scene walks on the broken up rocks and it moves as if it were a pad or a sponge. It wasn't a rock moving because the street moves with the rock. It happens a couple of times during that scene.
Revealing mistake: After the Ghost Rider escapes from jail, he is shown pulling his chain whip off of his bike and wrapping it around his torso. As he lifts his leg to mount the bike, the section of chain near his right hip can be seen to pass through his jacket, revealing that it is a CGI chain, not a real one.
Continuity mistake: In the scene near the beginning when Johnny Blaze falls from his bike and raises to look at Mephistopheles, when he lowers his cane to the ground it lands to the right of his foot yet when it flips to a frontal shot the cane is in the centre of his body with no time to move the cane.
Continuity mistake: Since Johnny is unable to move while on his motorcycle, the zippers to his jacket sleeves are down, but when he reaches the train yard they are now up. Also, before the bike drives off, Johnny's feet are attached to the sides of his bike. When the rear tire starts spinning, his feet are now planted firmly on the ground but in the next scene, when the bike drives off, his feet are now back in their original position.
Visible crew/equipment: After Johnny completes the helicopter stunt he chases the TV van down the highway. You can see the camera and crew reflected on the van sides.
Continuity mistake: In the movie where Cage is making the jump over the semi-trucks he crashes. You'll see that he skids up against the wall and hits his head. In the next shot you see that he is laying on the ground about a foot away from the wall when his crew shows up to help him.
Character mistake: After Nicholas Cage jumps the line of trucks and lands on his head, his team race over and immediately pull off his crash helmet to see if he's OK. Anyone with first aid training or experience of crash victims would know to leave a crash helmet in place, as it could cause further spinal injury to pull it off. The helmet should only be removed if the victim is not breathing, and in other cases should be left in place with just the chin strap undone.