N
90% of my riding is at my place in the UP.OP, I noticed your location of West Michigan. I have ridden MANY thousands of miles in west Michigan on numerous ATVs and motorcycles over a 25+ year period. Never had a problem with flats. I realize that doesn't help you much, but I just don't see the sand being the problem. It sounds like you have tried a lot of different things. You said you don't mind buying all new wheels and tires, and that is probably what I would do at this point. Study up on what your buddies are running then get those. And sell the old stuff to recoup some of the cost. Life is too short to keep dealing with this!