If you cut a lot of green stemed bean then you need a specialty rotor. But it has some threshing and separation problems and can be a little rough on things. So to fix that you can add Gordon Bars from our host to get better threshing and separation. Or as Gordon says,"get the best of both worlds." See ATTACHMENTS at the left side of the page. Plan B would be to get a modified rotor from St John Welding.