nighthawk750.freeforums.org

I successfully tried this mod to increase carburetor richness because I was running lean due to K&N air filter and Vance & Hines exhaust: http://www.nighthawk750.com/mods/carbneedlemod.html

Total cost of mod: $0.80 for eight #4 stainless steel washers!

I ran into only one snafu; the star needle retainer (SNR) would not go into place until I slightly trim with a razor blade the tit that holds the SNR spring in place. Then it went together perfectly.

Now, my '03 NH750 really wants to run!

This is useful information. I just tried to put 2 washers on the needle and could not get the star fastner to turn, so I only put one under it. The real number is 1mm spacing (.5mm per washer).
I really think the true problem is the pilot jets should be 38s or 40s ( they are 35s). I think the older CB750s were actually even larger. They must have been under a lot of pressure by Calif. to mod the bike for emissions.
I plan on trying the 38s and ordered them from a guy on ebay.

poncho

I got my 93 with clogged jets all around so I bumped the pilots to 38's I have a V&H 4:1 and I still have popping during closed throtle decelleration, I guess it's time to shim the needles too, huh?
I also went up 2 sizes on the main jets to 118 if I remember correctly, runs nice at all speeds, just pops on decell.