I'm thinking fuel pump:

[smoak]

Are you sure it is a round mikuni and not a Chinese JinBo knock-off?

Mine is the same bike as yours, and it had a JinBo pump which started to fail on me. I just replaced it with the new rectangular genuine mikuni vac-pump, and it starts right up first hit now, and the motor idles a lot better.

I thought about going with an electric, but I worried about wiring it up. I have seen people wire them to something like the radio hot wire, which is only hot when the key is on.

My concern is that if I turn on the key and then have to step away for a moment that the always on electric pump will flood the carb... Or, do the elec pumps have built in safeguards against that?

Smoak