i have a big bear that will only run with the choke on and about 1/2 throttle it wants to cut out and die but if i take the choke off it wont run at all. idles perfect. is it a carb issue or something like the cdi? ive had the carb apart a couple times cleaning it but it doesnt seem to help. the slide doesnt open as well as i would like almost like there is a vacuum leak somewhere. it was sitting for a couple years before i got ahold of it with gas in the carb. any ideas? im not use to the mikuni carbs