Originally Posted by
jim p
When I was a kid, I had a bike with a generator lighting system where the generator rolled on the side of the tire. When I used the generator I felt like I was going nowhere fast and I only used the generator when going down hill and when I had to have a light. I am guessing that the generator was probably about a 3 to 5 watt drag on my engine. So this should compair with the loses in the hub. If you put a generator light system on your bike and ride you should be able to decide if the hub is right for you.
This is a bad comparison. The tirewall rub generator is consuming much more than 3-5w to produce 3-5w of power. Having ridden both rohloff and a sidewall tire generator, the latter IS going to be noticeable. The rohloff is like riding any other internally geared hub (sturmery archer etc.).
Maybe someone will do a study where they compare how many watts somebody is losing through the rohloff hub vs a derailleur system. I doubt the loss will be meaningful to anyone who actually rides these.