I don't know what year carb i got. It is an 01 or 02. The main thing is the nozzle. Use an S8 nozzle. You can get one from JetsRus has the nozzles. There is also an S7 nozzle available if you need to go leaner. The nozzle is the needle jet that is NOT replaceable on Keihin carbs.
I am running a 32.5 pilot, stock needle at 4th clip from top, and a 390 main. I really haven't put much time on my motor so there maybe some adjustments to the jetting.
I posted this because there is not any good info that I found on these carbs for a 250r motor. My suggestion would be if you were to get one is put in a new nozzle and needle that you can get from Honda for a CR250, simply because that would give new parts. I will have to look at which one I am using because the numbers change per year, I am pretty sure it is an 02.