I use castrol 2t in all my bikes,25 to 1 in my 125/400 and at 50to1 in my ktm ,ktm hasn't had a rebuild in four and a half years,when we were kids all our bikes ran at 20to1 like the factory manual said,they used to keep on keeping on,I think as we get older we tend to analyse everything instead of just riding and having fun
Cheers scotty