Hey i've got a honda express 50cc here in athens. It ran pretty well before the "nipple" part of the pet cock broke off. It should still run well, though, with a new pet cock. I put new tires and tubes on it. Asking $230, which when you include the new tires and tubes is less than I paid.
I'd say it is in about average shape for it's age (1978).
Colin
404-277-1007