I remember hearing that the gear noise is high on these but will break in and quiet down. I ran mine on the street for a minute just to make sure everything was rolling right and it was unbelievably loud. Louder than the Tekno's that I have seen at the track. Is that indicating improper mesh (motor pinion/c-diff spur is fine)?

Should I check the shimming of the diff gears? I assembled per the manual with one shim on each left and right side of the diff outdrive bearing inside the housing.