Fallon
Super Member
I concur. I ran a 7' Ford 917 behind a L3200 (25hp PTO). It was a bit slow in grass but would keep up with a 5' rotary given the extra width. Actually tall heavy green grass was worse than a lot of brush. The grass just had more mass & fibrous material. Brush was more woody, but on a cubic foot basis, less dense & tended to cut reasonably cleanly. It did good up to a little over finger sized material.You have enough HP to run a 7' flail to mow normal height grass and weeds. But cutting brush with it is very questionable. It will require all the HP you got, and maybe more. One option when running an oversize flail in tough conditions is to scoot over after the first pass and only cut a lesser width.
I run a 10' Vrisimo flail with 60 PTO hp in grass and when I do the first cutting in the spring if the grass has gotten a little too long I have to significantly reduce ground speed or take a narrower cut after the first pass.