49cc bike is startin but diein after 10-20 sec...

How come my pocket bike is doing this?? where do i set my choke at? is the air valve supposed to be open or close during start up? Can yall help me and tell me some things so i can start it up right.

And is it supposed to be leaking from the connection ob the exhaust pipe to the engine??

doesit die when u start to ride or when its warmingup

Sounds like you got a air leak. Check to make sure your carb is nice and tight and your cylinder. That might be the problem.
-Randy

The choke is closed for startup and until its warmed up and when you get your carb tuned the leaking out of the exhaust will almost stop and if that dont do it you should add some RTV copper silicone gasket maker to the gasket thats there because you have a exshaust leak you should do this anyways to stop the exhaust leak....

-What kind of bike do you have?
-have you messed with any screws inside the bike prior to this?
-if youre using pullstart leave the choke down when you pull but
as soon as it starts up flip the coke switch back up to let the airflow
-the fuel leaks are usualy normal when you have a new bike it will go away after about 1 tank