Forget the car - use the bike
Sunriver has 33 miles of paved bike trails inside the Sunriver Resort area. The bike trails are masterfully laid out. They are safe, out of the car traffic, and the signage and directions are excellent. When you do have to cross the road, the bike lanes are well marked. and the car drivers generally yield.
Because Sunriver is relatively flat, the bike trails are good for all ages. The bike trails lead to every activity in the resort.
For those who like trails that are a bit more demanding, head outside the resort towards Mt. Bachelor. There are numerous mountain bike trails in the forests, mostly intermediate or expert.