Carb slide binding

[SS109]

Hello all. First post here and now a KDX owner. What I have is a '90 KDX 200. It is pretty much stock, as far as I can tell, other than an FMF pipe.

When I purchased this bike the throttle was sticking and the previous owner had said it had been sitting for over a year. I assumed it was probably a cable needing some TLC and/or a good carb cleaning was in order.

When cleaning the carb I found the slide to be binding in the carb body. It appears to start binding with the slide 1/4 open to around 1/2 open. I know the carb is thoroughly cleaned and I also tried the slide without the needle and it was still binding. It feels smooth when I push it by hand but there is significant resistance in the 1/4-1/2 open area compared to the rest of its travel.

Can anyone help me figure this out?

 

[reepicheep]

Did you pull the slide out? On my 95, the chrome (?) plating that is where that slide contacts the carb body was about half worn off. Its a thin vertical strip up each side of the slide.

A previous owner was running a foam air filter with big chunks out of it, and a filthy airbox, so they were no doubt sandblasting the poor thing for a long time, and it took it's toll.

Those edges are the bearing surface between the slide and the carb, so I assume when they get "gone", the slide will bind and hang up.

New slides are pricey at $60 or something, but not the end of the world. There is a number on them you will have to match if you go aftermarket, I assume if you get it straight from Kawasaki, they will send you the right one.

It could also be your cable, did it move freely when you had the carb disconnected?

It could also be that annoying little plastic collar that sits inside that spring inside the slide and holds the other end of the throttle cable in place. Is that in right?

(note that all these suggestions are based on my 95 200 carb, I am assuming yours has that same carb... if you have a CV carb it's a different story...)

 

[SS109]

Cable is working good.

The binding is happening with me holding the carb in my hand without the throttle return spring/collar attached. Just moving the slide up and down by hand (even without the needle) it binds up.

I'll try to post up some pics as the carb and slide both show scuff marks.

 

[SS109]

OK, here are a few pics.

Well, I guess I can't post pics as the forum software says they are spam for some reason. How do I post the pics on this forum? I even tried to add them as just "copy & paste" but that wasn't allowed. I even removed the "hXXp" and still not allowed. I'm a member of several forums and have never encountered such trouble posting pics.

 

[SS109]

Anybody?

 

[sr5bidder]

up load to photbucket then copy and paste the immage code under the pic in your album

 

[SS109]

I tried that but the forum software kept saying I was posting links/spam. Well, I'll try it again. (In post preview it appears to be working now...weird :coocoo: )

First pic is where the binding starts. Second pic is the upper limit of binding.

 

[SS109]

 

[SS109]

Well, instead of buying a new carb (just replacing the throttle valve wouldn't have fixed it) I got creative. Take one Dremel with polishing wheel and compound and get to work!

It took quite a while but now I have a carb that doesn't bind like before. No, it is not perfect but it will get me through until I can find/purchase another carb.

 

[porterdog]

Where/what did you grind? The top center of the bore (visible in the first pic of post 8) looks really weird...

 

[SS109]

I polished all the contact surfaces that the slide came in contact with. It took quite a while (about 3 hours) to do as the polishing compound takes off very little material on each pass.

If I had more patience I could probably get it near perfect. I figured I had nothing to lose, since the carb was toast, so I gave it a shot. I am happy with the results.