Always use good quaility two stroke oil in the fuel mix, however two stroke oil should not be used in the chain oil tank, this should be a non fling oil, or a bio chain oil, which will stick to the chain even on the bottom of the bar, light oil will just throw off the end of the bar and not lubricate where must cutting is done.
DO NOT USE SAE 30 IN THE FUEL MIX.
Husqvarna man, February 2010