Brushless motor getting hot - in 30 seconds

[jcb]

After racing in the damp at the weekend I appear to have a problem with my Nosram brushless motor.

While racing it became intermitant with power delivery more like an on off swtich rather than stuttering, tonight I tried it again and have the same problem so I changed the sensor cable and that has not cured the problem. The other thing I noticed is that it gets noticeably warm within 30 seconds of use, say around the same temperature as it was coming off from racing after 5 minutes. The can did also seem to get warm quicker on one side of the can!!

I have not tried another motor with my speed controller and after taking my nosram one apart nothing seems obviously wrong and the rotor spins freely in the bearings.

Any ideas?

Oh and it sounds horrible to, not sure how to explain it but it doesn't sound right!!!