Ask 100 people you'll get 100 different answers. I'm partial due to my involvement, but we've tested nearly every oil that is commonly used, and many times there are things in every oil that you won't like. Valvoline is a good oil, but make sure you get the vr1 with zinc, many times the oil on the shelf isn't the stuff you want in a racecar.

Other companies use high doses of zinc and other additives, but the particle size is so huge you'll filter the good stuff out in no time.

TJ Racing oil was built with reliability in mind, made for alcohol, and made to work with your bike transmission. We won a ton of races in the 600cc engines along with the larger engines.