Seems these carbs do not have a one size fits all. Appreciate all advise.
Thanks.

 

I prefer to slightly enlarge the slide hole vs. the DJ diaphram spring. I found when using the the lighter rate spring, at constant, low throttle cruising I'd get some surging and poor mpg. I Figured the light spring was causing the diaphram to bounce at low, constant throttle as the vacuum signal must of been just enough to start lifting the slide, then closing, causing my surging. Swapped in the factory spring, drilled out the slide port hole and all surging is now gone and I don't notice a difference in throttle response. Mileage is s bit better. 100 miles vs 90...

 

Matty,
Did you use the DJ needle or go back to stock?
Thanks

 

DJ needle. I thought I could tune out the surge with different needle heights but nothing helped until I swapped springs.
Im running the 128 DJ main, DJ needle on the 3n.

 

The stock spring is certainly longer than the DJ spring. I did not "mic" them for differences in diameter.. I also just reinstalled the stock spring on my 2152 kit for test purposes.. My power above 7k now feels muted.. I wonder if the shorter DJ spring also allows the slide to extend farther up @ WOT..

 

Matty,

You are about sea level like me so looks like I better hold on to the old parts especially that stock spring. Just incase I get that surge.

 

I'm using the DJ kit with the slide drilled and have no fueling issues, fires right up hot or cold every time. No backfires or stutters smooth roll all the way to wot. about 175 ft above sl. When going to the high desert it's just a quick turn on the idle when climbing up to elevation. The CVK carb is a POS no doubt about that but the one advantage is they work well in high altitude from 8k and above.

I would have to rejet my KDX for above 8k or it would just die on the ridge at Kennedy meadows. One time I forgot to switch them out we came down from KM and went straight to Jawbone. I totally mind farted and burned a perfect hole in the piston.