Anyone who hikes around in these areas you speak of, will clearly see ( unless blind ) that motorcycles and other off road vehicles run freely where ever they wish to go. The fences, and local laws related to these OHV,s and the approved routes is no barrier to those ( lawless ones within the OHV community of riders ) that have no respect for such things. There are those of us who would prefer to walk through these wildlands and not constantly come across the damage the OHV's constantly do to the terrain. Then there are those, who view these lands as a place where they can indulge in thier interest of riding thier machines through a variety of landscapes, without barriers to stop them. Since there are realistically no meaningful negative repercussions for these OHV riders to consider ( at this time ), thier prospects of being caught highly unlikely because of the fact that enforcement in the area only shows itself on rare occasions, they will continue to proliferate through these lands seeking thier form of fun, at the expense of ( in the minds of many ) the natural bueaty that resides in those special lands.