I did this with my LX26 and use it for light muni. The frame will hold a 2.4" tire width, but it doesn’t have adequate height clearance for a large volume MTB tires (Continental Trail King, for example), so I had to use c-shaped shims between frame and bearings. Home Depot sells thin aluminium stock which works nicely – easy to cut, sand, and bend.
And if you are handy you can also install a cheap sidepull brake, which works fine.