Questions about 72v 5kw water cooled BLDC Motor

[KaptainJEK]

I purchased a 72v 5kw water cooled BLDC motor about a year ago and I am noticing the power draw has gone up significantly. I tested without a load and I am pulling 300 watts full throttle. Is that about right or is that high? The shaft is not free spinning and takes a little force to turn. The only other variable is I have not been running the water coolant through the motor but have had no problems. Would this cause problems over time? I've seen no signs of over heating. Could the shaft be bent causing added resistance causing more power pull to explain the difficulty in turning the shaft? As a test, could someone power up a 72v 5kw water cooled BLDC and see what the power pull is full throttle without a load? Are there any tests I can run on my motor to test correct function? Thank you!

[Natsukawa]

Hi KaptainJEK

I don't have the same motor, but to compare to something.
72v 4Kw E-Max Hub motor full throttle 825-850 rpm 375W. (I have the tire on it and little brake pad rubbing)

I think general its a good idea to use water cooling if the motor is designed this way, I'm not saying that you will destroy your motor but shorten its life span.
If you suspicious that your power draw is higher then check the bearings, the shaft material in most cases are hardened ground steel, you need some serious power to bend or break it.

[KaptainJEK]

Thanks Natsukawa. 

I don't know if that is a good comparison or not because I know at full throttle I am @ 6000 rpm.