Stalling
Read your plugs and see what color they are...black is running to rich white is to lean..they should be just a little brownish. Check that the Petcock is fully open, the choke cable is set properly an check that the throttle cable is set perfectly with no slack, you may just have to readjust them...then too Replacing the fuel filter may be a good thing. If it was dropped you may of had some sediment in the tank that went to the filter. A kinked fuel line...even a loose spark plug wire could cause it. When it gets warm you have more resistance...IF you figure it out please get back on the FORUM and let us know what you found...it's only fair to tell us...