Yes...it could be any of the above.
Does this happen when you go a long time at slow speeds or when you are running high throttle under a heavy load?
Of course, make sure all of the fuel line connections are tight and the fuel bulb is laying horizontal or arrow pointing up while under way.
Check to see if you have the updated fuel pump. If you look at the hose from the fuel filter to the fuel pump, does the hose go to the upper pump nipple or lower pump nipple. If it goes to the lower nipple, you have the updated pump.
Do you have an external water separating fuel filter? Be sure that all is well there and the nipples and pipe plugs are sealed and tight.
If you do not have the updated pump but have an external water separating fuel filter, you can do a small test that will help you determine if the pump is really the problem. Get a 5/16" barb'd double nipple and bypass the fuel filter on the engine. Disconnect the fuel filter on the top of the engine completely and connect the two hoses together with the double barb'd fitting. We used this as a fix for the faulty fuel pump while waiting for Honda to come up with a new pump solution. This was only on early models like yours.
Take the motor out and run it. If the problem goes away, then you need the updated pump.
Even though I am pointing out the pump, there are many other potential causes. As long as the bulb is not collapsing, then at least you tank and venting should probably be ok.
If the pump does not seem to be the issue, you are probably sucking air from somewhere. That is where a clear plastic hose and a couple of double barb'd fittings will help....by placing the clear plastic hose in the fuel line at different points to see if there are air bubbles in the fuel. You can start at the fuel filter on the motor, run the motor without the hood and if there are bubbles, then move the clear hose along the fuel line toward the fuel tank. When you get to the point where the bubbles go away, you have just passed the trouble point.
I hope this was not too blithering at this late hour.
Mike