Recently saw a factory video on the new Stihl Four Stroke engine they are producing now. It is a dry sump engine & is oiled with a gas & oil mix like a two stroke. There is a by-pass tube from the intake manifold to the crankcase, when the piston goes up it pulls the mixture in to crankcase & back down ,back to the manifold & into the combustion chamber. It will most likely be in their whole line of their equipment. No weight figures yet for bare engine. >>>>>>>>>>>>big max 1935>>>>>>>>>>>>>>>>>>