I have been riding bikes for over 58 years. I have been repairing them for most of that time also. For the last 20 or so years, I have been using Shell Rotella oil in all the bikes that I service, 5 or more a week, with great results. If my customer wants synthetic oil, I recommend T 6, or Mobil 1, for their bikes. I feel that I have a vast amount of experience with oils, and motorcycles. Again, it is not "just what I think" like you, it is from years of experience.I have also used Blackstone , to check the life of oils on many bikes with really good results. So, besides "your opinion" what do you have to back it up. I am out of this thread, because facts speak louder than opinion's