Most say there are no real disadvantages to bogging but some of the things I found are:
Breaking very expensive partsChanging tires to often from wear and tearUse more fuel when using more engine powerTakes a toll on engine performance out of the mud.Its not cheap to lift and modify suspension
Gladwin BogDozers BogThe MoundsFowlerville BogPerkins BogDelany BogOutlaws BogMonsters of Mud BogThere are many more these are just a few
