ID a needle for me

[lornop]

Hey guys, got a used 2014 300ec a while ago. Just got the top end done on it and since then it hasnt been running as good. I dont have to use the choke to start it, and if I do, it revs really high until I shut shut off the choke. The idle screw doenst seem to do much and my bike wont idle more then about a minute without giving it a bit of throttle.

So I pulled the carb apart and I have a 38, 170 and the needle has no markings on it. It has a blue top on it though. Any ideas?

If i get one of the recommended needles (NEDW) will I need to put new jets in also? I ride from 0-300m and 15-30C.

Thanks for any advice, its my first 2 stroke so any help would be appreciated.