try 500-600 rpm on the drum, concave 25-35mm
Top sieve 13 +/- 2mm
Bottom sieve 6 +/- 1mm
Open the disawning plates, so that you don't move to much material to the walkers.
Make sure u have the slotted pre-concaves without keystocks (too aggressive)
Give it a try. If it is showing losses, make a killstall to really check if there are any. It is a bit tricky in canola!