New to modern 2 strokes..need opinions

[chiro972]

I have been riding my 200 kdx 220 for a couple of weeks now and I think I need to look at the carb jetting, but I'm not sure. I haven't ridden a modern 2 stroke, so I don't know if it is just normal. Anyways here is how it runs: It idles very well. Will load up if I just let it sit for more than a minute, but cleans out quickly. Just above idle it sputters a good deal, worse when cold (I don't use the choke) but still does it when warm. Once I get that cleared out and open the throttle more, revs build quickly and speed picks up. Then if I open the throttle more, the revs build so fast it feels like the clutch is slipping (it's not) and the bike builds speed fast.
Now I haven't looked at the plug yet, but I'm thinking that the midrange is a bit rich. Does that sound right? If so, what should I look to adjust? Pilot? Needle or airscrew?

Also, I am running 32:1 Mobil 1 synthetic two stroke oil and I just noticed that all my riding gear has little splatters of oil on the back. Is that normal? or am I running too rich, or too much oil?

Thanks folks!

 

[clutchcover]

It sounds too rich to me. If the jets are stock, that is almost a definite. If you get the jetting spot on, it'll accelerate even faster. What you are experiencing is what we like to call the powerband. The kdx's are fairly tame compared to a motocross bike, but it is still there.

 

[kdxsam]

If I were you, I'd go to www.fmfracing.com and click on "2-strokes". Then, click on any one of the pipes and their should be jetting specs box on the right side of the page. After that, just do what it says and eventually you'll see a page with all different bikes on it, go to yours and see what they recommend for main/pilot jets and needles! It worked great for me on my KDX200. But, of coarse their jetting recommendation is for best results with an aftermarket pipe. Good luck!!

 

[Tom Ludolff]

I would try turning the air screw out 1/2 turn at a time to lean the idle. If you get to 2 1/2 turns out from seated and it is still loading up, then go to a step leaner pilot jet.

 

[Tom Ludolff]

You'll want to go back through the older posts on this sight. There are a kizillion posts on jetting!!

 

[canyncarvr]

http://justkdx.dirtrider.net

Check out CDave's input on the matter. It's right! HE'S right!

I read only the first sentence of your post. If you haven't done it yet, it's about 100% given that you are too rich.

But then....after most riders do it, they're STILL probably too rich! ;)

(me too!)

 

[Fred T]

You didn't mention if you did anything to get it more air. Cut holes in the airbox lid or remove it. Thats for starters, THEN jet it. A stock 220 "basic" jetting guideline is 42 pilot, 145 main, Stock needle in clip #2. Move needle to #3 and a 148 main in the colder weather. Adjust A/S to best throttle response.

 

[davidg]

I just went to the fmf site to checkout there jetting tips. They have the wrong size jets listed for 220. Use C-Dave's jetting recomendations for starters.