There are multiple local companies offering scooter tours of the Vietnam capital. These tours range greatly in thematic focus (street food to historic landmarks) and duration, and depend on the individual provider, but details can often be agreed upon on an individual basis. On these tours, an individual driver is normally assigned to each visitor, who then hops on the back of the scooter as a passenger. Helmets should normally be provided.

One motorbike tour of Ho Chi Minh personally tested out by the editor is Non-profit Student Tour, an incredible initiative that works surprisingly well.
The coordinator links up tourists with available local student volunteers, allowing the students to practice their English and bringing overseas visitors into contact with locals. Each traveller is assigned an individual driver (this even works with larger groups). Drop them a WhatsApp message to arrange the date and time.