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So I thought I would pop in and give an update. I got all the parts in and put the new radiator cap on. I burped it several times and got the fan to kick on. Everything seemed to be working well. I took it for a spin around my neighborhood. It didn't seem to go above half on the heat gauge so I thought I was done. Well, then it happened. It just all of a sudden spiked again and started blowing fluid out the reservoir and of course then the fan didn't kick on. Back to square 1.
The only thing left was the head gasket which I was glad I ordered. I found a great manual, thanks to JR, on my scooter and started in on it. I got the head gasket off and sure enough it's pretty shot. Here's a pic of the old gasket

Next on the agenda is to clean the residue for the old head gasket off, install the new one and put it all back together. I'm going to do a valve adjustment while I have it out. Once I get everything back together it should run like new. I'll keep you all posted.

So I finally got the time to sit down and place the order for my radiator cap. Here's my plan. As soon as it comes in, I'm going to put it on and hope it finally takes care of the issue. I am hopeful. I went ahead and ordered a head gasket just in case. My thought was if the radiator cap still doesn't solve it, the only other thing I can think of is a head gasket. Somehow too much pressure is building up in the engine. I decided to go ahead and order it so that it will be here just in case. It was only about $15 so it's worth it. I might not have to install it but at least I'll have it here just in case.
Does anyone have a good video or instructions on how to change the head gasket on the Linhai mp250a. I've seen the video regarding replacing the head gasket on the vertical 250cc engine. I believe mine is a horizontal 250cc engine. Is the process pretty much the same or is it different? I'd like to take a look at it to get an idea what's at stake.

Sorry in advance for the length of this post.
OK so I made some headway today finally. I had a friend of mine that recently bought a Jonway and we were doing a coolant flush and installing a couple other accessories on his. While we were waiting for his to cool (part of burping it) we started to work on mine. The thermostat came in and I installed that. I also went to Advance auto and bought some cooling system clean and flush. We went through that whole process with the radiator cap off. I actually saw the fluid circulating this time and actually got the fan to come on. I ran it for about 20 minutes and it never went above half on the temp gauge. It just continuously flowed. The thermostat was opening and closing as it should. I could actually tell when that was happening. We drained everything and put coolant back in and had the same success with the coolant in again the radiator cap was off. Thought it was all done. I put the radiator cap on and left it running. Within 5 minutes of doing that fluid starting back flowing out the reservoir and then the temp guage went all the way to the top and the fan quick working since it was now low on fluid.
My friend mentioned to me that he thought my radiator cap was bad. He had the same situation with his car and it had the same symptoms. He thought the spring on my radiator cap was too easy to compress. It makes sense actually. When I put the cap on, the system builds up normal pressure and the cap spring just lets the pressure off back through the reservoir. Once that happens, it is low on fluid and then overheats. I have a good feeling about this. I think we solved it. I'm going to order a radiator cap and we should be all set. In the end I think it was a combination of several things - crud in the system, bad thermostat, and also a bad radiator cap. I'm hopeful it will get back on the road soon. I hope this is helpful. If anyone has any other suggestions, let me know.

That small hose coming from the top of the radiator is the only logical thing that would possibly circulate when I open the radiator cap. When looking at the radiator from behind, there is 1 large hose in the upper left (goes to the radiator cap connector), 1 large hose in the upper right (goes to the thermostat housing on the engine block), 1 large hose in the lower right (goes to the water pump), and the really small hose coming out of the top middle of the radiator (goes to the back of the radiator cap connector). That small hose seems to be the only possible place to see coolant circulating from. I still can't understand how there would be fluid circulating. I'm baffled.

OK so I have removed the thermostat (I have ordered another one and am waiting for it to arrive) and am not any further along than before. I still do not see any circulating. In looking at the radiator connector, I am not sure where it would circulate from. Here's a link to one just to show you what I am referring to. .roketapartsdept.com/products/ROKETA_MC_54B_250_RADIATOR_CONNECTOR-18316-612.html" rel="nofollow" target="_blank">.roketapartsdept.com/products/ROKETA_MC_54B_250_RADIATOR_CONNECTOR-18316-612.html
The main hose (about 1" in diameter) going out the bottom of the cap goes to the top left of the radiator. There's another hose that goes to the overflow tank (about 1/2" in diameter). There is a small hose (about 1/4") that goes from the back of the connector to the top middle of the radiator. That is the only thing I could think would actually flow. I saw some air bubbles come out of that but that was pretty much it. I got one of those oil siphon pumps you use to drain oil from a lawn mower and hooked it up to it and pumped some fluid out just to make sure nothing was clogging that line. I did get some hard black chunks come through that hose. I just replaced all the hoses connected to the radiator except for the one coming out of the bottom of the radiator going to the water pump. I replaced that one about a year ago. Does anyone have any ideas where to go from here?

I have burped it about 5 or 6 times and I'm not getting anywhere. It still runs hot. The fan kicks on but when the temperature is about 3/4's. It's kind of random. It is acting like there is still air in the system. When I run it with the cap off, there are continuous bubbles of air that keep coming up. That still happens every time I burp it. At some point the air bubbles should stop unless it is indeed a head gasket and compression is backflowing through the system. I have removed the thermostat and tested it in boiling water and it opens all the way. The water pump looked good when I took it off and inspected it. The wierd thing is I haven't seen any black spots in the coolant which I would expect if the head gasket was blown. The black spots I saw before were in the reservoir so I am thinking they were just little pieces of rubber from the reservoir cap. I'm not sure what else to do. I have done everything that I know to do. Any other ideas?