The first hub was the NuVinci N360 - After ten revolutions, the wheel averaged a spin time of 19.2 seconds, with the longest spin time of 19.8
|That is one blurry photo. Schwinn High Sierra, WTB hub.|
The second hub was the WTB freehub on my Schwinn High Sierra - that spun for an average of 46.7 seconds. The longest spin for this setup was 48.1 seconds.
Next I tested a Shimano Nexus 7 speed internal hub. This hub actually had the worst friction of the lot, clocking in an average spin time of 12.3 seconds, with the longest spin at 13.2 seconds.
Finally I put my 1973 Raleigh International in the stand. I picked this bike up from a day laborer a few months ago and haven't done a rebuild on the high flange Record hubs yet, so this was going to be a crapshoot. Average spin time on 38 year old Record hubs? 1 minute 11 seconds, with the longest spin clocking in at a whopping 1 minute and 13 seconds.
In conclusion, while there is indeed some friction drag on the NuVinci hub, it is less than the drag on a Nexus, and not too different than a free hub. If you want to ride without drag, find yourself some Record hubs. Otherwise, I don't find the friction drag on the NuVinci to be a real factor; a Nexus has more drag, and the NuVinci is only 20 seconds or so less spin than a regular freehub. I rode that Nexus for a long time and never noticed a difference. If you are racing, that might be a factor, but if you are commuting, I think the benefits of the hub outweigh the drag factor of the NuVinci.
The NuVinci is $399, available through your bicycle shop.