Originally Posted by interested
If I understand you right, then you claim that chain riding the same sprocket all the time causes less wear than a chain riding in several (+4-5) sprockets? You can't be serious then.
Of course you need change the single sprocket more often than you need change a cassette. Personally I don't find it a significant disadvantage against internal gear hubs that it is so; you need to change moving parts from time to time, so sometimes when you do a chain change, do a sprocket change too. Same goes with cassettes. I can buy nice nickle-chrome coated cassettes for $30 at my LBS, and I have a hard time believing that such a cassette wouldn't outlast a single sprocket at least 3 times.
.....
Your first reply was that you have never personally tried a Nexus hub.
I have however tried a deraileur system (for about 10 years now), and am contemplating a Nexus Inter-8, Shimano's "Ultegra" level system, for commuting purposes simply because I am tired of destroying my drivetrain.
And whilst I have never tried a Nexus system (yet), I would think a single sprocket, thick BMX steel one, would last longer than a cassette, probably 3 cassettes even. As for chains, it is even better economy. Note that I am a year-round commuter including winter, and part of my route goes through foresty trails. Mud, grit, dirt, hills, salt, puddles, roads, etc etc. 35km daily.
I hope the Nexus lasts alot longer than my deraileur system!