Was 2013 its last production year, or was he retired at the very beginning of 2013, or at the very beginning of 2014? If an engine was retired before being sold in the 2013-2014 single-engine packaging that was around before Revolution, then that's a huge clue that points towards these being knock-offs. I think the easiest way to find out is to confirm whether or not they were on store shelves, but I still can't find any footage or claims from anyone regarding that...
(Also, Duncan's Trackmaster or Plarail toys don't even have pistons. o: I think you're referring to his cylinders. A piston valve is something inside of a cylinder.)
(Also, Duncan's Trackmaster or Plarail toys don't even have pistons. o: I think you're referring to his cylinders. A piston valve is something inside of a cylinder.)
Creator of upcoming series "Sudrian Tales"
Amateur voice actor
Still haven't painted FFF's Daisy lol sorry my guy (i promise I'll get that airbrush kit soon)
Amateur voice actor
Still haven't painted FFF's Daisy lol sorry my guy (i promise I'll get that airbrush kit soon)