Well, after all this, it seems like Lazyrider nailed it and the battery was the problem all along. Not expecting it to work, I pulled the battery from the Daytona, hooked it up to the Speedmaster, and (to borrow Glazer's Georgia line) it started right the f#@k up!
I returned the five-month-old battery to the store, the kid behind the counter checked it and said it was bad, and they replaced it at no charge. I got everything back on the bike, and it's running just fine so far. Not that I trust my voltage-meter-reading skills anymore, but with the motor running the battery's reading just under 15 volts. I think that means my charging system is working, right?
Thanks for everybody's help. It felt good to get it all back together and get in a short ride yesterday. Now I can focus on getting tires for the Daytona...
Will
