I decided to test my bikes to see which freewheels have the lowest coefficient of friction when freewheeling. My test was simple. I decided to pedal backwards while the bike was on the stand. I tested a Regina 7, a Shimano 7, a Suntour 6 and another Suntour 6. Only the one of the Suntours did not cause the wheel to rotate backwards during medium speed reverse rotation of the cranks. I assume this means that that freewheel has the lowest coefficient of drag in freewheeling. This is not a real big issue for me because my habit is to hardly ever coast, but I still think the test is valid. All my freewheels are very very clean and well lubricated. The Regina has the best rep but the test shows otherwise, even though the Regina is NOS and all the rest are quite used.
Garth Libre in Miami Fl. USA