The choke may be getting stuck. You gotta pull the carb apart again and clean out the choke valve.

 

More than likely is the pri/res switch (fuel shut off) change it over to reserve. For some reason these things do not like running off primary due to faulty switch. If you run it on reserve you will be fine. Mine did the same thing..

 

I must apologize for posting the same response in the same thread. I hope you find/found your problem and have been able to fix it..

 

i will start for replace the spark cable and end ruber piece

 

In addition to checking the tank vent, you might disconnect the fuel line at the carb and check the gravity flow into a clean container. Rust or dirt at the tank valve filter, or a partially clogged in-line fuel filter can cause similar trouble....fuel is adequate at idle and low speed, but fuel doesn't feed fast enough to supply higher demand....
Jim