I run a 30ft flex. I can run 3.5-4.5 in green stem beans 50to60 bu. I started with a rochele rotor, rebuilt rock trap with serrated bars,heavy vanes in cone and new rasp bars on the front of the rotor. My 2388 had 1100 separator hours and the elephant ears,wear bars, vanes and rock trap were worn out. lots of soybeans and sand have been through this machine. It had been turned up to about 300hp, or so I was told. It runs so smooth in the tough stuff, as you know, that I forgot about the HP until I blew a rotor belt and then a PTO clutch. The PTO was due to a selenoid kicking in and out and probably the HP had nothing to do with it. I turned the HP down one half turn and don't notice any difference. Fall panican, wet corn stalks still make her grunt but I would not look back on the Axceller. If you need to do as much as I did it is well worth the money. I did my own work so the project was affordable. If I had your 1688 I would give the screw a half turn or so to the right. It's only $3.00 fuel. Make some noise and smile. My next project will be to update the rotor drive to the 500lb spring.
