I just finished tearing apart my old XR and I cleaned up everything, like new and I had to put in a new camshaft and rocker arms. Actually, I had them refilled or hard face welded, or whatever that is, only because the parts were not available in the country that I am living in. Anyway, the inside and outside of the motor and the rest of the bike looks perfect, now, spotless, all painted and I just finally put it all back together, again. This old tank has sat in the garage for over 4 years and I finally decided to fix it up. I cranked it up, today (started on the 3rd kick) and everything is running smooth, now, except it is smoking extremely bad and when I put my hand over the end of the muffler it sprays out oil. I am sure that I need new rings and/or possibly valve seals, as well. I would have replaced them when I had the engine all apart, but, as I said, here in Costa Rica, it is very hard to find parts, especially for older motorcycles. What do all you experts out there think I should do? Fortunately, I can have a friend bring me these parts from the U.S. when he visits me in a couple of weeks. I know that the cylinder and piston and everything else is fine. I cleaned up the rings, but, maybe they were still too worn out to work, again and I do not have a way to measure the gaps. I did not do a valve job, but, I will do that now. I adjusted the valves and had a motorcycle mechanic friend double check them, for me. I also, put in fresh, clean, Penzoil 20w50, synthetic, because that is the best I could find in the little shop here in my area. Many say synthetic and many say regular, so I am not sure about my choice with oil. Any suggestings on fixing this smoking problem? The smoke is white or grey and it is not blue or black.