I picked up a 93' XR200 that needed some work. Upon getting deeper into the engine I found out that the head was pretty much toast (valve guide on the exhaust side is wallowed out and the valves were pretty much hosed). I opted to just order a whole replacement head and valves. I found one for 96 XR200 on eBay for $120 that came from a reputable seller. I installed it today with new gaskets and new piston rings but now with everything bolted together the engine does not turn over at all. It has absolutely ZERO rotation. The strange thing is, once you take the valve train/cover off the top of the head everything rotates perfectly in the engine. This makes not sense to me..