225 dx carb?

[Walkerallen]

ok just put a new throttle cable on my dx and now i have a question. on the throttle slide, the needle, that plugs the hole in the carb, has a "c" clip and what looks to be an adjustment. does anybody know what this is for or how it works?

[MonroeMike]

Needle clip, page 170.

http://72.52.143.80/~trikes/ytm200&225-fm200_clymer_manual.pdf

[Walkerallen]

thanks mike