Well as some of you know I have a 91 XR250R that I had the entire engine rebuilt,Cylinder Head,Cylinder Head Cover,All internal parts,Cylinder and Sleeve. When I got it back together it was burning oil, Well the ones of you that read the post a good while back wanted to know what happened so it ended up being the Piston Rings, The thing is I haven't had the new rings put in yet because I have been waiting for them to arrive at my Dealer, What I want to know is this-ok you know when you change rings you have to be very carefull because the slightest bend can break them? Well you can take the rings that were on my bike and twist them like a twist tie you put on bread,potato chips etc and they won't break!! What could have happened, My dad said if the bike overheated then it would make that happen. But all my riding was during the cold months and I wasn't riding any tight trails so I know it didn't overheat from not having enough air blowing across the fins, Remember that I discovered that the right side exhaust Valve wasn't operating properly and was forcing most of the gases out the left one, Could this had let the bike get to hot by not letting it breath enough or something? I want to know what most likely caused it before I get it back together and then have to tear it down again because it happens again. So do any of you know what caused this? Thanks Matt