[DougAz400ex]

So I picked up this quad a month ago. It has a replacement carb that I finally got to idle great but as soon as I touch the throttle it bogs and wants to die. The old carb has an air screw on the bottom of the carb on the engine side where the replaced carb seems to have almost like a screw plug that can’t be turned. Any help would be greatly appreciated.

 

[Here 2 help]

What brand is the replacement carb? The 'air screw' you refer to is a fuel screw - it only affects idle and is capped at the factory so it cannot be screwed with and mess up the idle, but if it's a Chinese carb, it is calibrated for gas without alcohol - alcohol requires more fuel to be mixed with the air, but the standard setting is one turn more than is required for a smooth idle to compensate for changes in fuel quality and alcohol affects fuel quality greater than differences in the cracking process used to manufacture gasoline. If it idles fine, then the problem is the calibration of the carb. The installer of the carb is responsible for it's final calibration.

 

[DougAz400ex]

What brand is the replacement carb? The 'air screw' you refer to is a fuel screw - it only affects idle and is capped at the factory so it cannot be screwed with and mess up the idle, but if it's a Chinese carb, it is calibrated for gas without alcohol - alcohol requires more fuel to be mixed with the air, but the standard setting is one turn more than is required for a smooth idle to compensate for changes in fuel quality and alcohol affects fuel quality greater than differences in the cracking process used to manufacture gasoline. If it idles fine, then the problem is the calibration of the carb. The installer of the carb is responsible for it's final calibration.

I was able to figure it out. It ended up being the slide needle. The one that came with the carb had no notches for adjustment. I pulled the one out of the old carb that I got from the guy I the quad from and it had the notches in it. I moved the snap ring down one notch and now it runs like a top! Thanks for the reply I appreciate you time.

 

[Here 2 help]

Congratulations on calibrating the carb and welcome to the forum

 

[chasemo12]

Congratulations on calibrating the carb and welcome to the forum View attachment 5281

hello im very new to this forum and im trying to figre out how to make my own discussion, cant seem to find how to start one and it has me stumped. thanks in advance

 

[DougAz400ex]

hello im very new to this forum and im trying to figre out how to make my own discussion, cant seem to find how to start one and it has me stumped. thanks in advance

Try clicking the “New” chat icon at the top of the page

 

[Here 2 help]

hello im very new to this forum and im trying to figre out how to make my own discussion, cant seem to find how to start one and it has me stumped. thanks in advance

Click the forums sandwich icon between the NEW icon and your account avatar - select the forum you want to start a discussion in, once in the forum, click the CREATE POST and create you discussion