im new to this page ive been trying to diagnose this quad that I recently got ill just jump into the details. so I got this 2008 baja wilderness 250cc atv from a guy on craigslist the quad is in good shape he bought 2 wilderness quads one a 90 the other the 250 anyways they have obviously been sitting for a while but do believe they were still like new because he had all the paper work and they still had the nobbies on the tires. so when i got it i cleaned the carb out i took it apart the way it should and cleaned out all the jets and put it back together ive worked on quite a few quads and dirtbikes anyways i put a new spark plug in it drained out the old gas put new gas got a battery for it then attempted to start it. after a couple of tries with the electric start button it fired up only with the choke on and it would run for about 20 seconds maybe longer at times it had a really uneven idle and it was running really crappy if i hit the throttle it wouldent rev up at all and it would try to die out, if you turn the choke off it dies almost immediately and will not start with the choke off it becomes harder to keep running as it warms up any ideas im stumped and dont know where to start