carb screw

This may sound like a stupid question, but can someone explain what the carberator screws are, and their locations and what effect would it have turning them in or out (leaner or richer).

I have looked through the manual and I can only find jet exaplainations and the pilot screw location on the bottom of the carb. What is the allen key screw on the side of the carb?

Greatly appreciated

I think the allen screw you speak, is the throttle stop screw (take it out and make it shorter, or, buy a YZ screw), The FUEL screw is the one just in front of the big nut on the bottom of your carb. If you need more jetting info (how to, etc) feel free to contact me or search past threads. :)

Would that be the float bowl drain?

The float bowl drain is the small brass allen screw on the side of the carb bowl at the very bottom. The only screw that is not described in the manual is the throttle stop screw (that is why I assumed you were talking about that one, Sorry) It is the black screw facing down. The fuel screw is in a recess (hole) in front of the access plug (big nut) on the bottom of the carb. Sorry about the confusion.

The fuel screw works just the opposite of a pilot screw. Turning it out makes the mixture richer. Since you live in Canada, you probably aren't saddled with the long throttle stop screw.

Hey, check out the March addition of Motorcross Action. It's a 'must read' if you have a thumper. It explains exactly what the fuel screw does, how it differs from the air screw of a two stroke, and best of all, gives detailed instructions on how to adjust it.

Hey, check out the March addition of Motorcross Action. It's a 'must read' if you have a thumper. It explains exactly what the fuel screw does, how it differs from the air screw of a two stroke, and best of all, gives detailed instructions on how to adjust it.

How would I get ahold of that issue? Is there a online archive of that info?

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