30x30 esc typical fan temperature
 

Just noticed this on 2 of my maclan mmax picos, my muchmore 30x30 esc fans get very noticeably warm, bordering on hot to the touch, just from turning the car on

BEC is 7.4V and the fans spin just fine, measuring around 26-40 Celcius at different spots of the fan. Is this something I should worry about? The manufacturer says the fan is powered directly from the battery

You should be measuring the temp of the ESC, not the fan, be sure to enable the auto cutoff temp limit that is provided by the ESC, if you experience thermaling with cutoff enabled, then it may be time to replace/upgrade the fan. Generally you can control thermal issues by gearing:

• What gearing for upgraded electronics?

It wasn't the esc getting hot, it was the fan getting unusually hot. Turned out to be 8.4V to a non-HV fan