
I have a 99 KDX220 that was jetted stock 42p 145main and no airbox lid
In the summertime. My pre-mix is Amsoil dominator 40:1
It ran great but the typical 220 signoff at high-mid rpm.
It has had a wiseco piston installed in the topend.
I purchased a parts bike which is a 95 KDX200, which came with a Pro Circuit 'works' pipe and what I thought was the stock carb (35mm).
I put the pipe on but kept the stock silencer and then opened up the 'stock' 35mm carb. Found out that it has been bored out to 36.5mm and rejetted.

Pilot is 50 and main is 165! The carb has no divider plate etc...
So thinking it was gonna be pig-rich and relatively safe, I put it on my bike along with the 1174 needle that came with the 200s (and on this bike).
I immediately got a wider stronger powerband, with a slight bog at about 1/4 throttle (it's 90+ degrees here with 80% humidity). I can tell it's rich at idle @ 2.5 turns out plus w/ lots of smoke throughout the whole throttle
So I replaced the pilot w/ the 42p from my old carb and bought a 155 main jet. I know these are big jumps down but from what I am reading here, this is the jetting many of you guys use on the 220.
However I swapped the 1174 needle w/ my old 1173 needle since it's a tad richer. Figure this would keep me safer with the smaller main jet.
Now the bike will not rev out past 1/2 throttle. It acts like it's way too rich on mid/top sputtering etc.
So to recap:
700ft elevation
90 degrees avg w/ 70-80% humidity
KDX 220
stock reeds
PC works pipe
stock silencer
no airbox lid
50 pilot
165 main
1174 needle 3rd clip
runs good, slight bog from 1/4 throttle
switched to
42 pilot
155 main
1173 needle 3rd clip
idles perfect runs like crap from mid-throttle on. Does the 1 size richer
needle make THAT much diff? Why are the 220s richer than the 200?
I am probably going to do an RB carb later on down the road. But I would like to play around with this carb in the meantime.
Let me know what you guys think.
TIA