I know there's a million threads on this but I have a question regarding shimming the N65 needle.
The carb had a dynojunk kit including drilling the slide and lighter spring. Had a 45 pilot 170 main.
I got rid of the kit, bought a new slide and cleaned it up the best I could without removing it.
put the velocity tube in, 45 pilot, 180 main and N65 needle. Kept the lighter spring. Turned the AF screw out 2 full turns and she fired right up with little effort. Hot 1 backfire thru exhaust revving it. Turned it in a 1/4 and took it out for a ride.
Seemed to run a little smoother thru the whole rpm range but still got an occasional sneeze.
A few thoughts/things I've noticed.
There's a slight movement of the throttle to take up slack. Could tighten it a little. Very little
May be a little low in the idle once it's totally warned up and it only sneeze from a dead idle when warm and cracking it quickly. Not always
should I try swimming the N65?
As black and gummed up as the slide area and throat was im sure it could used being tore down. It sat all this year til i bought it 3 weeks ago
It does seem to run good tho.
I should add it has drag pipes with baffles and stock AC with a K&N filter.
I could try 2 full turns out on the A/F screw again. I attribute that backfire and little smoke to playing with the throttle before I ever started it.

 

Try turning the idle mixture back out 1/4 - 1/2 turn.

The cough/sneeze when you crack the throttle open is likely due to a lean condition which could be the idle mixture screw being adjusted too lean, or an accelerator pump not up to snuff, which leads to this:

At over 10 years old, I would recommend a carb tear-down, cleaning & rebuild.
A parts REBUILD KIT is $20.00

 

I did pick up an accelerator pump but the old one appeared to be in excellent condition so I left it.
Also, the reason I turned it in a 1/4 turn was the backfire and smoke on start up but that could've been playing with the throttle before I ever started it. I'll try backing it out that 1/4 turn.
I do plan on tearing it down soon.

 

OK, bad idea. Sluggish as all he!!. Turned it back in 1/3 and holy sh!+ what a screamer. Just have to make sure the main isn't too lean. Suppose to be able to run stock jets but I went from 170 back to the stock 180 and I'm not so sure it's enough. The pilot stock is 42 but I've got a 45 in it.
what does everyone else run with this N65C needle?

 

Put the stock 42 back in and way better. Now I can maybe richen everything just a tad as I may be just a tad lean. Before when I turned the screw out it also made the pilot richer. Too rich with the 45. Now the whole rpm range is running more evenly if that makes sense.