Rotella synthetic 5W40. Good protection, reasonably priced at WalMart. It may be a "truck" oil, but I'm unaware of significant differences in "truck" internal combustion engine demands vis-a-vis oil. Also, see below. Besides, change your oil & filter frequently, and does it really matter anymore, providing you're not using the cheapest stuff out there. I try to stay with the SF & SG oils (older designations) as they do not have the "friction modifiers" which screw up wet clutches. For the BSA's, any non-synthetic, SF/SG oil. Change the oil frequently (every race weekend), and what does not leak out or get burned up is carrying enough metal filings to require change out (no paper oil filter - only steel screen to keep the big bits out). Oil used to be cheap - it is now a significant cost. Still, it is cheaper than rebuilds.
For everyday cooking, I use olive oil. For deep frying, it's hard to beat peanut oil. Mobile 1 Racing 4T.
Switched to Repsol from Motul and noticed a positive change in the shifting of the bike. Could be in my head. But Repsol stays in my bike now....
Mongo, If you changed the polling feature so it was limited to say 15-20 items instead of 10 items--I could have listed other oil brands.
Amsoil, got a corporate account set up and it saves me a little money! Also did some research and found how good they really are.