If you are cutting about 50-75 acres you can get by, but go real slow and dont hurry machine. Nothing bigger than 16 foot head for sure. If you have more acres, find a spike tooth cylinder and replace rasp bar, will make a tremendous difference. Just dont try and cut corn with spike tooth in machine, it wont work. Also make sure you have extra risers or fishbacks as we call them on your walkers. Put the ones in that are short and go in center of walker. Start at front of walker and every 3 feet put them across walkers till you get 3 feet from rear. Also extend your walker pans at rear of walkers.
We used to cut rice with rasp bar 4400s w/216s back in the early 80s. Starbonnet was our variety then and we went very slow, 1st gear, about half way on the VS. I'd hate to try to cut some of todays high yield, tough straw varieties. Tom