Factual error: The motorcycle is not right for the period. It looks like a 1970's Kawasaki stripped down. Look at the rear wheel (too big), motor is 2 stroke (not one), and the exhaust has a muffler.
Suggested correction: There is no such thing as a one stroke engine.
I don't really follow the technology, but I happen to know there were at least one-stroke prototypes years ago. That aside, a "single-stroke" is possible, but may depend on how it is defined. That is, there will be an accompanying reverse "stroke" ["to" and "fro"], perhaps categorizing it as two-strokes? The "factual error" and your correction may both be correct, using different perspectives or definitions.
Factual error: All the couples on the train are modern and not correct for the period. Trackwork back then wasn't very good, considering the speed that the back end of the train is going it probably would have derailed long before it did. The caboose and the rest of the train seen to be just shunted off the track for the dramatic crash, realistically it would have flipped over and gone over the trestle.
Factual error: On their journey, Rooster is bragging about his navy colts, when actually his sidearm is a Colt .45 Peacemaker, also known as an Army Colt M1873.