I have used a 2nd motor with a regen capable controller to tune a motor under load. Idk how much you will want to spend on it or how precise it needs to be but its a quick and dirty dyno if you have lots of motors and controllers laying around.
Most hub motors have a brake flange you can attach sprockets to. Running a chain between the 2 motors gives you a poor man's dyno.
You also have to contend with people accusing you of trying to build a perpetual motion generator.
I have used a 2nd motor with a regen capable controller to tune a motor under load. Idk how much you will want to spend on it or how precise it needs to be but its a quick and dirty dyno if you have lots of motors and controllers laying around.
Thanks. Here was my version. The 80100 RC outrunner is being loaded by a 9c hub motor doing regen. Made me feel a little better to send at least some of that power back to the battery. Its way easier to tune this way than to look at the display while riding.
I have also thought about making a similar device with a pump, fan, or an old exercise bike. Seems like an all electrical version is less trouble and most efficient.