[HoosierDaddy]

DD does not recommend multi weight oils in 2 cycle engines. My understanding is that in order to achieve the multi weight characteristics the viscosity improvers are lineal rather than spherical as in a single weight VI. When the oil is cold the VI curl up which makes it more flowable. When the oil is hot the VI straighten and stiffen to provide higher viscosity. When in this state the VI is subject to shear which will lead to lower viscosity and inadequate lubrication. IMHO running a multi-weight oil for a short period would be ok. The problem is not knowing when the viscosity will be affected by shear. I am not familiar with synthetic oils. They may not break down the way natural oils do.