I have heard of two instances before where the carb started binding both of which were in Losi's. That vehicle has an unusual servo placement that makes it a little tricky to get the linkage set up correctly. Which vehicle do you have the engine in?

Also in general when this happens with any carb it is caused by the linkage pulling on the slide at an angle. When this happens the slide wants to rotate in the carb body. The only thing that stops this from happening is the idle stop screw which when installed sits inside of a groove which is machined in the slide. with the strength of the servos pulling the slide against the idle stop screw repeatedly small burrs will start to form which will cause the carb to stick. To fix this completely remove the idle stop screw which will allow you to pullthe slide out. Take an x-acto knife and run it against the edge of the idle stop groove at a 45 degree angle to de-burr it. Then clean, put a few drops of after run oil on it and re-install everything. Now test it by hand, if everything moves freely when you pull on the slide by hand you've taken care of it and everything is good to go. Put everything back in the care taking care to make sure the linkage is now pulling strait on the slide and is not trying to rotate it and your good to go.

If the linkage is not set up correctly this will eventualy end up happenig with any carb that you use so guys please take care that when installing engines this is done properly.

Regards,

Ron