The 500 pound bike is the "elephant in the room". Marketing departments ( and that movie with Charlie and Ewan ) have sold the bejeezus out of the idea of taking a large heavy bike into situations which might prove difficult. BMW and other manufacturers have sold large numbers of bikes to people who bought into this notion. Some people have found out the hard way that a 500 pound bike is a poor choice for riding off road. Some riders are coming to the realization that a bike that weighs well under 400 pounds ( or even better, well under 300 pounds ) is a better tool for the job of riding off road. A lighter bike is more fun, safer, less likely to snap your leg bones if it falls on your leg, easier to pull back onto the trail if things go wrong, etc. I suggest your apparent trepidation regarding riding the large heavy bike is your common sense and wisdom making itself heard. If possible you may want to add a smaller lighter bike to your collection. There are many great light weight bikes you could choose, and riding them off road will probably bring back those nice memories you have from your youth.