Tubing (for free) in Sunriver?

Alright - I’m well aware of the nuances of free tubing in Bend, and I know you can pay to tube in Sunriver, but is it possible for a person not staying in Sunriver but who has their own tubes and vehicles to do this float? I guess I’m asking if it’s possible to access the river and park in proximity to it. I assume I’d shuttle it either with two cars (park at both ends) or a car and a bike. What say you wise folk?