I had flax (linseed for us!) last couple of year's and with all our mod's in our R62 and only a 300 Kg_Ha crop (Very poor season) I found that we had to run at about 10 mile per hour to get it full enough so as to thrash as best we could!! We had lot's of problems with trying to keep the seed in so I tried going quite fast and that made all the difference, in fact I think Tbran's 'crop trip hose"(CTH) on the front would work very well in direct headed flax, as I had some trouble with it not sliding under the table auger very well!,