ok thank you, i took the whole carb apart when i got it a month ago, but the guy i got it from didnt know anything about them so i didnt really know what i was getting into. Plus this is my first JD sled and i love it! I was playing around with it a few hours ago and the main jet needed leaned out, ...

I have a 78 spitfire and i have the mikuni butterfly carb. It will idle fine and take off fast but only reaches about 25 MPH. if i take the air jet out, on the tob of the carb, it wont idle but will start and run fine in the higher rpm's, just dies when i stop unless i put the choke on then it idles...