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carb question
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Posted by: zedicus00

if you increase the size of a carb on an R and dont change anything else about the way it was setup what would you do with the jetting?

its getting more air an fuel since the carbs bigger so u would want to go a lil richer right?

Posted by: edz250r

Agree!

Posted by: beerock

no smaller

Posted by: zedicus00

bee yur bein kinda a pain in my ars today u know it??

jus givin u **** man... care to explain that answer though?

Posted by: ESR250R

when i went from 34mm stocker to the 38 a/s i went up in jetting. i am running a 190 main on my lrd motor.

Posted by: beerock

a smaller carb has a higher air velocity then a larger carb so there for it will suck more gas as well.

A larger carb has less air velocity then a smaller carb so therefor it will suck less gas

this is with the same exact motor setup just a carb swap.

Posted by: zedicus00

has anyone ever measured an intake boot? technically if yur carb is bigger then the opening in yur intake or sumthing then yur not really getting its full effectiveness r u?

and yeah going from a 34mm to a 38mm you would prolly still hav enuff velocity to actuallygo up in jetting... and that was an A/S carb u went to so that would help. i see what hes saying now though...

faster air equals more vacuum. but u can only pull so much air through so big of whole b4 it starts becoming a restriction...

complicated, basically i jus need to baseline and start over on my jetting, o well ive got free time.

Posted by: beerock

on top end YOU WILL PICK UP rpm's and power, it mayt onylbe a little bit, but just think you dont have to worry about the crap stock carb anymore. also, changing pipes will give you bigger boosts then with the stock carb.

zed if i were you I woudl go with a 39mm carb over the 38 a/s I know alot of people like the 38a/s for the bottom end. But honestly, when i ride my R im either on the gas or off of it and keepin my rpms up so why need a a/s carb? thats my opinion though.