just a long shot but make sure the fuel tank is venting. Try loosening the cap and see if it runs. If a tank is not properly venting then it gets a vacuum in it and the engine starves of fuel.
Other things I have seen cause problems like this are electronic modules, tight valves that eventually open up and power goes away, and coils but you have already replaced those. Once I saw an electronic fuel pump do this also.
Last, make sure that time is the component causing the issue and not that you turn the opposite direction hard, or hit a bump about that time in using it. Sometimes we think the trigger is one thing when it can be something else.
