Max RPM's shut it down or she'll blow...

[dubbstepped1]

Could somebody, lease ****"HELP"**** I have a. 79cc harbor freight preditor motor/ when I start it , it takes off @ Max RPM's/ with no throttle, what-so-ever, I have to shut it down, before she blows up......................
WHY WOULD IT BE DOING/THAT??????

 

[Harquebus]

Throttle lever at maximum? Return it to low speed. Idle speed set too high? Use a screwdriver.

 

[manchester1]

If it's a new engine, you need to loosen the nut on top of the throttle arm so it springs back.

 

[dubbstepped1]

"Ok", Thank you very much, prb solved, one more question, also when I'm trying to start motorbike, its shooting a flame from intake manifold/carb like it would be kinda like a backfire, out of carb with a flame????????????..........why....