Bob sez:

 I currently have a 175 main, 45 low. The tube the main jet
is in has holes along the side of it. I also have a tube with no holes in
it. The 180 jet I have fits into this tube only. The 180 jet has larger
diameter threads. This tube doesn't seem to screw into the carb as far. The
float bowl goes on fine though.
What are the purposes of the holes in the tube? Should I find a 180 jet for
this tube?
I can't remember exactly what needle I have in there. I know it's one with
the notches on top for adjustment. I noticed that I can move the needle up
and down a little (1/16") independent of the slide.

oooooooooooooooooooooooooooooooo

The notched needle, you have the infamous dynojet kit installed. Some
people love em, some people hate em. The dynojet emulsion tube takes
mikuni jets, not keihn jets.

Skinny Kenny