I would like to learn all the best ways to enlarge and contour ports in 2 cycle engines of 25cc-50cc. Can you please post links and photos. The tools used would be of great interest. Also if some of this can be done more accurate on a Mill , I would like to know that. Is stoning the sharp edges after cutting a good way to keep liner from cracking /flaking or wearing piston rings. Of other interest would be good port timing limits. I think a lot of data in one thread would be of interest for a lot of others. Thanks Very Much Capt.n