Carb Question

I keep hearing the terms fuel screw,air screw,idle screw and pilot screw on the carb and i have no idea witch one is witch.

Can anyone help me

i'm pretty new to dirt bikes and i was able to rebuild the carb on my 03 crf 450 simply by following the owners manual. once you actually get into the carb all the pictures make sense and you can identify all the differnt jets and screws.

First off, git yer whichs streight.

Witch= crazy mean old bitch that rides broom

which = ? either or

the big thumb screw on the side is the idle screw, all it does is push the slide up. The fuel screw is in the bottom of the carb in the hole. You cant see it unless your a very special person with super powers or have the carb layed over.

there is no air screw on an FCR, unless you installed of of those trick PAJ jets that you can adjust (but even then you have to pull the carb or at the very least the air boot). I put one in my 426 (pretty slick)

The easy way to tell a fuel screw from a air screw is look at the placement of it. If it is aft of the slide, its an air adjustment screw. If it is fwd of the slide its a fuel adjustment screw.

They both control the idle mixture--- they just do it differently.

If it is an air screw, and it is running rich you back the screw out to give it more air. If it is a fuel screw and running rich, you screw it IN to reduce the fuel.


02 CFR4550R, 96 XR440R, 88 CR250.

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