thanks for calling me on that one, good eyes there. that is a calculated output based on actual outputs measured at much lower rpms. my guess is that we would NEVER see 250 watts from that motor at any speed. bet we would top out at 100 watts or so with a 12 volt nominal set up and then start going down from there until it burnt itself up.
the volts per rev on these things is only 0.7volt per 100 rpms. (measured value) and the restance internal while running as a generator is 1.7ohms. (the calculated value based on actual readings)
i have had the same little motor, but the 450 watt version running at those speeds though and have seen 280 watts at ~7,300 rpm (speed of armature)for short intervals. (measured values)
the 36 volt version does only slightly better at 0.9volt per 100 rpms (measured value).
these are fun little motors and are fine as motors but the low volt per rev when used as a generator is the real killer here unless we can over drive the darn things...which we can with a pedal machine and gearing easily, but not so easy with any kind of wind application.
it's all good clean fun :)
kind regards, dave