I checked the spark on the Vespa, and nothing. Turns out the battery was dead. New battery, and good to go. The hardest part was pulling off the crash bars and side fairings.
My son helped me clean the air filter, and in exchange I let him take a ride around the neighborhood. Big smiles. Future Opponaut? Time will tell.
[UPDATE] I am concerned my new headlight is draining the battery. Any ideas how to test this theory?