I started harvesting wheat yesterday with our new 7088. Plenty of power but I cant get it to keep from throwing wheat out the back.Both rotor and of the sives. My current settings are small wire concaves, 8 on the clearance setting, sloted grates,  vanes in the mid position, top sieve .25" front, .50" to the back, bottom sieve .25", Fan 1100 rpm, Rotor 900 rpm.  I have tried most every combonation and nothing makes to much of a difference.The only thing I havent done is speed up the vanes. What am I missing?