Hello to everyone first of all as I am new here and new to ATV's. I bought this ATV from someone who bought it from someone else and according to ID numbers, it was made Jan. 2008.the air filter housing had no, filter in it so I took some sponge type similar to what's used on the front of a window unit air conditioner except thicker maybe 1/2". I have yet to find out exactly, what I have yet but it looks like the TAOTAO 250D. the carb says TAO on it but, on the left side of the carb. while sitting on it appears to have two screws threaded into it part way like someone tried to block off the holes and one looks like a wood screw lol! and the other is finer type thread and larger diamater but,it's plain to see it doesn't belong was told that's where the choke was hooked up but didn't work right? on the right side of the carb there is one long screw with spring which looks like it belongs. my son inlaw told me the one with the spring is the idle speed screw but, doesn't act like it just know that turning it too far either way will kill the engine. he also told me the air/fuel screw was on bottom of carb and required an offset screwdriver being so close to the exaust doe's this sound right? it starts but doesn't want to idle real steady sometimes pops a little when revved and seems to idle too slow. any help would sure be appreaciated maybe a link to a photo showing the carb. screws I will have to get the ID info off it again tomorrow as I can't find the paper it was wrote on and I will post that info.  Thanks!    UPDATE! I found the name ZHEJIANG on the bike.  

yes it is a tao tao  zhejiang in a different production company for tao tao.
jialing is the same company as well.

the fuel/air screw can be located on the bottom but most of the time you find them on the side of the carburetor on the chinese models.

the screw with the spring is the idle screw but if it won't do anything but  make the atv die then you mostlikely do have a an issue with the fuel/air ratio.

turning the fuel/air screw to the left will increase the amount of fuel in the mix,  turning it to the right will decrease the amount of fuel in the mix.

however the choke being removed could cause some serious problems with tuning the carburetor or even hoping to get the fuel/air ratio right.  

Thanks verry much for the info! I don't see but the one silver screw with the spring on that side of the carb that is adjustable but, I did notice a small copper or brass screw on bottom of carb maybe the air fuel adj.I'm going to check out the choke section if I can figure it out first and see if anything can be done to get it working then, check the screw which I think might be the air/fuel adj. hopefully, I won't have to try and get another carb due to funds right now and the trouble of finding the right replacement. If I don't need new gaskets,etc. I might try taking the carb off and giving it a good cleaning out for the heck of it once the weather cools down some as I can't take the heat like I used to due to health problems.  Thanks Again!      

Well, I found the choke linkage it seems the bracket has two holes in the metal part one, a screw goes through and the other slips over a post which sticks out from the carb and looks right. The plastic piece which has the choke cable going through it has no where to connect? also when I took the air filter housing off I could not see a choke plate anywhere? I assume there was a linkage comming out the hole where the foreign bolt with a shoulder on it is and also,the choke plate should  be connected to this linkage. does this seem to make sense? The carb says TAO on it and says made in Japan along with some numbers which I guess I will need if I have to order a new carb. later on. I will have to get an offset screw driver of proper size as I found out the screw on bottom of the carb is in fact, the air/fuel adj. with exaust cool and motor off, I backed the screw out a little got it to idle better and the idle speed adj. seems to work more proper now once fully warmed up with no choke. also I noticed a little crud in the gas tank any tips on how to get that out?  

I can just about bet that your jet is clogged in the carb.  Clamp the fuel line, remove the carb, remove the bowl, remove the jet next to the main jet, check the main jet, have only ever seen one that was clogged. Look through the jet to see if you can see light at the other end, if you can't, its clogged.  I take a very fine wire (one strand from an old throttle cable works) and drill it through the crud in the jet,,,then I soak it for 10 or 15 minutes in parts cleaner, blow it out with air hose, reinstall.  Usually you dont have to worry about replacing the carb gasket.   When you re insert the throttle control in the top of the carb, just make sure the round slide goes all the way down.  There are groves on the side one short and one all the way up and down.  They have to line up with guide pins down inside the throat. the short grove lines up with the pin at the bottom of the throat.  The long grove on the slide lines up with the pin that is further up in the throat.   You can tell if its in wrong the first minute you crank it up, it will run WIDE OPEN.   Cranks up and normal throttle, your done, adjust your idle.  The screw with the spring is the idle screw.  The fuel/air usually to the left of that and usually offset at an angle.  The screw at the very bottom of the bowl is just a drain screw.  If you do have a f/a screw adjust it to your best throttle response, then adj your idle.  Hope this helps...have fun.  

sell the piece of *** learn your lesson, and never get one of them zong shen chinese quads again.