jjminor I had the same problem with a R52. I had 6 reverse bars in, took 4 out left 2 in at paddle end of rotor. Also have concave clearance at 4 speed at 550, chaffer 1_2, sieve 3_8 and full wind. This seemed to fix it for me.
Thanks Newman! I did just about the same and got much cleaner grain. I also found bean dust caked to a small section of the fan and cleaned it too. That may have helped a little. I did notice a bit more pacer activity from the cylinder discharge sensor but was not sending any beans over.My service man said if conditions change try closing the separator grate a little before reinstalling any reverser bars.