Not going to comment on the use of diesel as it seems to be covered but just a note on Harley oil. Basically, it’s crap based on independent comparison with many other brands. At our largest Harley dealer in this area, they of course carry HD oil but no one buys it. Reason is, they also carry Amsoil which has proven over and over through independent lab testing as well as real live riding to come out on top every time so that’s what bikers want. In fact Amsoil worked with HD to develop the 20-50 for the big V twin market. And no, I’m not connected to Amsoil but a long time user.