I was stationed in Hawaii when I was in the service. We went to Maui and rode the old, rough road to Hana and rode to Lahina, but not the full loop. They have now properly paved the road to Hana, but it sounds like the road around the west loop is still gravel in places. When we went back a few years ago, we drove. Taking a bike was too much hassle. If I go again, I will try to do some riding, but I am not a big fan of hills.