I don't think any of the Hondas are dependant on all bulbs and connections in working order to make a spark. Some other bikes do.. i can''t remember the brand name. Why someone would wire a bike so a freakin' bulb is a vital part of the ignition circuit is beyond me..
I have a honda C70 4-stroke that has a battery but it runs fine without it. (as long as the battery connector wires are twisted together) None of the lights work without the battery on that bike.
I know nothing about your bike but i can hazard a guess..
If you hotwire the ignition (and perhaps bypass the kill switch) you should be OK.. As far as i know, those two connections are the only ones that ground the coil and prevent spark. Of course you may have other issues as far as getting spark goes.
Hopefully someone who is familiar with your bike will contribute.. give it a couple of days.
You need a manual.. (don't we all :) Give Honda a call.. they have both service and owner's manuals still available for my PA50..