[RC-Monster Mike]

The mount itself will accomodate up to around a 47t without the need for clearance below the spur gear. Larger spurs will fit the mount, but clearance below it would be needed to accomodate the spur diameter and gearing would become limited with large spurs as well(has a pretty wide range, though). In a standard maxx truck, nothing larger than a 44t spur will fit between the chassis braces without clearance issues, but the mount itself will indeed accomodate larger gears. :)