Wont rev clean slight miss-fire

Hello,

Got my dax running ok but through the gearbox the bike seems flat - not reving clean almost like a miss fire.
if you mess around with the choke while ridding it seems to help the bike pick up and then will rev clean for a second or two?
any ideas? air filter?,
New carb kit fitted (seals and rubbers! and jets are clean,the points are set as directed new plug,coil maybe?

help needed

Kirk

Have you checked for air leaks around the air filter housing?

The problem is the air mix screw has rattled out!took the air filter off and put the choke sort of in between settings,and the bike is much better.

I hope I can buy the mix screw and spring or I am in the shit.