Recommended jets for 92 KDX 200

Joined
May 23, 2007
Messages
23
Likes
0
#1
Hello all, I am new to the KDX forum and just got a 92 KDX 200 in excellent condition. Problem is, I don't know anything about them. Could someone please let me know what the recommended jetting is with an opened up airbox? Also, it has an aftermarket pipe without silencer and I need a stock one, will a pipe off a newer bike work? Any info is good info.
Thanks guys! :nod:
 
Joined
Aug 31, 2006
Messages
76
Likes
0
#2
No, you need a pipe from 90-94. The stock one is super quiet which is great IMO. I just went through the whole jetting baseline process, and here's what I found to work: (I hope I'm remembering this accurately)

Main 148
Pilot 38
needle CGK in the fourth position
Air screw 1 and 7/8th turn out

I may try the 35 pilot this summer. Overall, this improved performance everywhere, but especially down low.

I would work your way leaner slowly so as not to blow anything up. It's worth it in the end to spend time getting this dialed in.
 
Joined
May 23, 2007
Messages
23
Likes
0
#3
Thanks, my other bike is a crf250x, and I know all about that bike, but this is going to be my spare that I will leave with my buddy in KY. I want to get it mostly dialed in before I take it down there.
- TheCowboy
 
Joined
May 23, 2007
Messages
23
Likes
0
#4
I didn't have a 148 main, but I had a 150 and I didn't have a 38 Pilot, but I had a 40, so I removed the 155 main and 55 pilot and dropped the needle and the bike runs awesome. I opened up the airbox and cleaned the exhaust. I can't wait to take it on a real trail ride, just ripping around my yard just isn't enough. Thanks for the help!
 
Joined
Aug 31, 2006
Messages
76
Likes
0
#5
Get the CGK needle. It's really good. Glad you got it going in the right direction.
 
Joined
Aug 31, 2006
Messages
76
Likes
0
#7
It's a different needle taper/diameter from stock. Search it. There's a few threads on it. I got mine at Pat's Small Engine Parts online, but I don't see the carb stuff on their site anymore???

Looking at my notes, I see I also ended up at 150 main, 40 pilot.
 
Joined
Nov 9, 2000
Messages
89
Likes
0
#8
I have a 92 kdx 200 which I bought new and after 14 years of riding with a race here and there, it's still chugging along. I have only made a couple of mods, a pro circuit pipe and fmf ram valve and I also dropped from a b8es to a b7es plug and picked up a big gain in off the bottom snap. The basic short coming of the bike is the soft and mushy suspension which can be up dated with after market springs but mine is stock. She smokes a little but I have only cleaned the power valve once in 14 years. I know-shame, shame, shame. I deserve the flames but when I have time to clean it, I go ride instead. Invest in a shop manual also. It's not a ktm or a crf but it's the best little trail bike I have found in 40 years of riding. moto
 
Joined
Aug 31, 2006
Messages
76
Likes
0
#11
Wow! An update, I finally got the 38 pilot, dropped teh CGK needle to the second clip, and put in a 148 main and this motor is incredible. Smooth from bottom to top and it really pulls AND spins up quick. (90 bike, stock pipe, airbox opened up)

Plus, no more smoke or spooge!!!
 

G. Gearloose

Pigment of ur imagination
Joined
Jul 24, 2000
Messages
709
Likes
0
#12
It should because thats a killer needle for that vintage, but thats a really lean main, beware.
 
Joined
Aug 31, 2006
Messages
76
Likes
0
#13
150 is stock, so I don't think it's that lean. THe bike wouldn't rev out very well with the 150, I could feel the transition from the needle, which is spot on, to the 150 which was definitely rich.

Don't worry, I race a 125GP bike and jet it for maximum power each day. I can feel when it's getting lean by the loss of torque/quick rev character. I'm nowhere near that. I'm sure I'm 3 jets fatter than optimum, and it would take a few leaner to do any damage.

I haven't worked out a chart for this bike yet, but it feels fantastic and it's not detonating. temps in the 80s, humidity in the 50s, sea level-1,000 feet. If anyone has data on their jetting experiences, I'd love to see some for reference.

YMMV
 
Last edited:

G. Gearloose

Pigment of ur imagination
Joined
Jul 24, 2000
Messages
709
Likes
0
#14
paab you have a lot to learn too. 150 is stock because the airbox is so restrictive it chokes the carb at high rpms. Its no way to run a railroad. Open up the airbox lid if you havn't yet, and set the main right with some plug-chops, else you are thowing away power