# Tunning B11 carburetor



## zca (Feb 15, 2005)

How to adjust the air and fuel ratio on B11 carburetor? Which screw to turn?


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## velardejose (Sep 9, 2004)

At idle its the needle, located at the carb's base, rear side
At higher revs there are jets (lil brass precision perforated screws) that control the a/f ratio
You can change the jets size for a performance or fuel economy config


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## zca (Feb 15, 2005)

the jets you mentioned are those in the carb which viewable from the top?

Do you mean i need to purchase other different size jets to control the a/f ratio or just by turning it?


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## velardejose (Sep 9, 2004)

Nope
In the standard carb you must take its top piece off, where the float and fill valve are located
The jets are at the top/bottom of the fuel bowl
You must change them
The idle needle just needs to be turned in til the engine hesitates/stumbles, then open it 1/2 or 3/4 turns and thats all
Of course this is a very short version of the whole procedure, I'm asuming you have basic mechanic skills and practice


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## zca (Feb 15, 2005)

Beside changing the jets, any other way to change the a/f ratio?
is there any screw to be open or close to control it?


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