spare carb laying around?

Have your dumb carb be rejetted back to a 230 main jet.
Have it set back to a 32.5 pilot jet. That is stock jetting for a blaster carb.
If you have any exhaust or any performance stuff that have to do with engine and intake etc. ask other people for where to start at!
 
if it just started doing this, it is not a jetting problem unless you have moved or something. make sure your throttle cable isnt bound up and make sure your slide is seated. dont change your main jet or your clip position, neither one affect idle in any way.