There isn’t a huge amount of load on the belt, but this motor has a bearing front and rear and is for driving pullies so there isn’t an issue with side load. The bearings may wear out eventually but not quickly enough for me to be concerned about it. Will last longer than a drill motor, outlived 2 drills I used before upgrading to the motor.Nice neat setup, but I wonder about the side load on the drive shaft bearing/sleeve, which is not an issue with a drill.
How tight does the belt have to be to prevent slippage?
Alternators have a small ball bearing and seem to last forever at quite high tensions but a lot of mills have bushes, something to keep an eye on maybe.