A sieve adjustment mechanism including a rack gear, a pivot handle, and an actuator, to mitigate lost motion/play in pivot link sieve assembly. The rack gear is movable between a first and a second position and connectable to a first sieve segment for moving the first sieve segment between a first sieve position and a second sieve position. The pivot handle includes a pinion gear at a first end of the pivot handle for operatively engaging the rack gear for moving the rack gear between the first and second positions and a second end opposite the first end. The pinion gear is rotatable about a first axis. The actuator is connected to the second end of the pivot handle for pivoting the pivot handle about the first axis to move the rack gear between the first and second positions.