Factual error: When Wilbur tosses Lewis onto the time machine, he should have broken or hit the glass covering the back half. And he is on all fours when the machine becomes visible, which shows he would have had his face hitting the driver seat, yet he scrambles back into the passenger seat without a problem, then is seen barely leaning forward to talk to Wilbur in the future.
Factual error: Goes along with the other factual error about the time machine: when Lewis falls, he falls into the bottom of the time machine, but when it becomes visible, a bit of roof is over his head. How could he go through the back half of the roof, but not all the way through the time machine? (00:20:35)