Now most owners swear by a certain brand for their own reason. It's hard to say which is best, but I recently saw a test done on one of those journal shows and after numerous brands had been tested (on cars), all of them came out equal. Now some claim that motorcycle specific oils are better than regular oils and some say synthetics are the best choice. I can definitely say that synthetics are the best oil (best protection) you can get, BUT where I live, synthetic oil costs 3 or 4 times as much as regular oil. For those of you that use regular oil don't feel bad. I have been using it for 20000km and after leaving the valves for 17000km (supposed to adjust them evey 10000km) I just checked them and wear was almost non existent. I think the most important thing about oil and the oil filter is to change it when you are supposed to.