Carb question non CR500

[Travis]

I had to change the carb on my qua because they 400ex has a pressed in seat that cannot be changed apparently that had went bad. The new carbs were $300. I picked up a parts bike for $50 and used it's carb. Here is where I have ran into trouble. It idles good, and from 3/4 to WFO it runs good. At a cruise in high gear or any gear at about 1/4-1/2 throttle it will bobble a little and stutter. It will sometimes backfire and stuff when you keep the throttle in that range. I could not find the chart that shows what part of the carb it is using around that range and I cannot remember. Help me out guys.

[Dakota Boy]

needle

[dannygraves]

yup, thats all needle there.

[Travis]

I think I will pull the one out of my old carb and stick in it. It ran tits with the old carb on before it went to overflowing and flooding without end.