"New" KDX220 owner, carb setup questions...

[UFS207]

Hi, I just joined. I bought a clean 2000 KDX220R a couple of weeks ago. The previous owner did a few modifications as far as I can tell: FMF "gnarly" pipe, renthal bars, air box lid "mod" and maybe he messed with the jetting.

Anyways, after riding the bike this past weekend it feels somewhat flat on the low-mid range....basically the motor just doesn`t want to "smooth out" and pull...it just kinda pops and misses until I really put a load on it, then it will pull cleanly. I dropped the slide needle to one notch from the top postion (was at the middle notch) and this seemed to help. I just ordered a bunch of stuff from bikebandit so I can really play around with the carb: new FMF "torque" reeds, 140-150 main jet kit, 40,42 & 45 pilot jets and a new carb float-valve-plunger thingie (bike leaks gas out of the overflow tube if you leave it sitting with the fuel petcock open). As a side note I`m currently running a premix ratio of 32:1 using Yamalube premix oil and 93 octane fuel. Fairly smokey but I`d rather play it safe.

If anyone could give me a few ballpark carb setup tips for my bike in it`s present condition I`d appreciate it. I have never "jetted" a bike before. I have read the carb setup tips on the main page. I`d just like to get this thing running smoothly as possible for my riding style which is 90% lowend stuff in the deep, deep woods...lots of 1st-3rd gear blasting with no more than 1/2-3/4 throttle usage.

ALSO: anybody have a spare airbox lid and snorkel? Bikebandit wanted about $80 for these items plus the gasket which seems kinda steep for some pieces of molded plastic.

Thanks for your time.

 

[Fred T]

First off you have to have the needle seat working properly to even begin to start jetting, it may end up running better after thats fixed. Clip #2 is kinda lean with the stock needle so put it back to #3 and ride it again after you fix the float needle.

#2 Read this: http://dirtrider.net/forums3/showthread.php?t=70290

3#; You don't want an airbox lid on that think or it will choke it off, save your money. The bike needs to breath.

ride on

 

[john_bilbrey]

I've got one lying around somewhere if you are interested in one, but I would recommend keeping it off. It's been a while since I was in the carb, but I remember something like a 42 pilot, around a 152 main, needle dropped one position (or was it raised one?) with Gnarly Desert Pipe/PCII silencer and lid/snorkel removed. Do a search under my posts from this spring and it will tell you what I ended up with. I was under the impression that I was way rich like everyone else, but turned out to be lean....

*EDIT* I forgot to mention I'm around 1000-1500 feet most of the time. I run 40:1 and it still smokes like a freight train using Bel Ray H1R and 93 pump.

 

[billc]

220 jetting

I ride from sea level to about 6000' in WA.My engine mods are:no airbox lid,Boyeson reeds,P/C pipe,Wiseco piston w/replated bore.
Mix=40:1 Mobil1 syn 2 stroke oil (very popular,good oil)
I spent a day trying different jets and needle positions.(I do have a very good collection of jets) Stock jetting gave me the best overall performance and has never fouled a plug.
Don't worry, you can very safely go 40:1 on your pre mix.(some guys go leaner = 50:1 with good oil)
Where and how you ride will determine what your jetting should be.

 

[Zerotact]

I've got the airlid, and pc pipe, stock jetting and the clip 2nd to last to the top. Never fouled a plug in 2 years... same plug. one season of hair scrambles

 

[dan1608]

I have a 03 220. With stock jetting it ran really bad, coughed, sputtered, fouled plugs. The Stock jetting according to the 220 supplement for the service manual is 145 main, 42 pilot, jet needle 3rd groove from the top. I ride in Michigan and my altitude is between 500 and 1500 ft. I changed my jetting to 140 main, 2nd groove from the top, 40 pilot. Runs like a different bike. No coughing, no fouled plugs, no oil splattered all over the swingarm.