RPM's of a typical Plarail motor? That would be a hard question to answer as there are many and with variables. The best way would be to test the the speed of an existing little motor removed from its gearbox and tested with a battery hooked up directly.
The variables would be in the gear boxes themselves as each specific configuration of gearing housed between the little motor and the axle can affect the speed of the wheels either higher of lower. Its a coincidence that you have brought this up now as I was just thinking about testing testing a whole bunch of little motors I have loose because I would want to slow down the newly released Tokyo Sakura Trolley because they look to be too fast for a Trolley imo. I picked up a couple of these Hotwheel Speed Reader cars a few years ago for this very reason after viewing Ucwepn's video below. BTW: don't we all miss his videos? Its important to note that I don't believe you can take the actual number reading of this speed test as literal. I would just use the results as a number relative to each test I do on each little motor in order to list them from slow to fast. I would also suggest using a AA battery holder with alligator clips for getting accurate test results compared to each other and using the same battery.
There is also a video below from ToysTrainsThings that shows the side by side comparisons of some of the different replacement motors available a few years ago which are probably still available today.
Hope any of this helps
![[Image: 413p-NMq-Zi-SL.jpg]](https://i.postimg.cc/py1dv5xr/413p-NMq-Zi-SL.jpg)
The variables would be in the gear boxes themselves as each specific configuration of gearing housed between the little motor and the axle can affect the speed of the wheels either higher of lower. Its a coincidence that you have brought this up now as I was just thinking about testing testing a whole bunch of little motors I have loose because I would want to slow down the newly released Tokyo Sakura Trolley because they look to be too fast for a Trolley imo. I picked up a couple of these Hotwheel Speed Reader cars a few years ago for this very reason after viewing Ucwepn's video below. BTW: don't we all miss his videos? Its important to note that I don't believe you can take the actual number reading of this speed test as literal. I would just use the results as a number relative to each test I do on each little motor in order to list them from slow to fast. I would also suggest using a AA battery holder with alligator clips for getting accurate test results compared to each other and using the same battery.
There is also a video below from ToysTrainsThings that shows the side by side comparisons of some of the different replacement motors available a few years ago which are probably still available today.
Hope any of this helps