Maxima K2 is my two-stroke oil of choice, it also has a bit of the castor scent to it (not full castor like the 927 however). In most applications I run it at 40:1 and 50:1. In the Goped 46cc HP engines I run it at 25:1 because you just have to if you want your engine to last because of the super thin chrome plating on the cylinders and being a single ring piston turning 14-22,000rpm.