When it won't start, loosen the lowest screw on your carburetor fuel bowl - it will have a hose connected to it, or a place a hose should be on there. See if it drains for a bit, should be a few tablespoons worth of gas or it's not getting gas to the carburetor.
Has to be a fuel delivery problem...
Either something is restricting the flow or the intake valve isn't doing it's job.
Like Dale said, check your compression - no pressure gauge?? Just see if it blows your tightly fit finger off of the spark plug hole...
All our government does is distract us while they steal from us, misspend our tax $ and ruin our country