as long as the exhaust port stays covered at tdc it will be ok for awhile but remember it is a 2 stroke and the skirts get flexed into the ports under pumping compression on the down stroke all be it minimal because of the small displacements we are dealing with it is the cause of the majority of piston wear besides the liquid sand paper we run in them and the average piston speed at 40000 rpm is almost 4200 feet per second on a 16mm stroke just something to think about