Is it truly a corn sieve (1-5/8 open slat) or just 1-5/8 cloz slat? If it is the open slat or corn sieve, i doubt it will work well in wheat. Beans, I don't know? I use 1-5/8 cloz slat for wheat and beans, then put in corn sieve for corn. I always run 1-5/8 bottom sieve and pre cleaner, but am sure it would help in wheat to run 1-1/8 all around. Hopefully someone else adds their two cents as well. Good luck.