At work, we have an old Carrier air handling unit and are replacing the fan shaft. The original steel fan shaft was hollow where the (2) fan cages attached. Our replacement steel fan shaft is solid steel and consequently weighs much more than the original shaft. Perhaps 80 lbs. compared to 15 lbs. Does this increase in shaft weight present any problems with operation? The bearings are flange ball bearings mounted to a reinforced steel cabinet wall.